1 00:00:06,320 --> 00:00:11,499 [Music] 2 00:00:21,119 --> 00:00:24,119 lca2022 3 00:00:24,480 --> 00:00:30,560 tna my name is joel um welcome back to 4 00:00:27,439 --> 00:00:33,440 day two of lca's sessions 5 00:00:30,560 --> 00:00:35,440 we have florian with you with us here um 6 00:00:33,440 --> 00:00:37,360 florian runs the education business unit 7 00:00:35,440 --> 00:00:38,960 at city network and has worked 8 00:00:37,360 --> 00:00:41,040 exclusively with open source software 9 00:00:38,960 --> 00:00:42,719 since about 2002. 10 00:00:41,040 --> 00:00:45,120 florian has been involved with openstack 11 00:00:42,719 --> 00:00:47,120 and ceph that's actually how i think i 12 00:00:45,120 --> 00:00:49,760 first met florian a few years ago at an 13 00:00:47,120 --> 00:00:51,840 openstack summit for my sins 14 00:00:49,760 --> 00:00:53,879 and is involved with the open edx 15 00:00:51,840 --> 00:00:55,520 educational project since around mid 16 00:00:53,879 --> 00:00:57,039 2015. 17 00:00:55,520 --> 00:00:59,039 florian is going to be talking and 18 00:00:57,039 --> 00:01:01,199 covering the basics of stereoscopic 19 00:00:59,039 --> 00:01:03,760 imagery and projection so we're going to 20 00:01:01,199 --> 00:01:05,680 discover how stereoscopic vision works 21 00:01:03,760 --> 00:01:08,159 and how we can trick our brains into 22 00:01:05,680 --> 00:01:10,320 perceiving depth from two flat 23 00:01:08,159 --> 00:01:12,320 two-dimensional images 24 00:01:10,320 --> 00:01:14,640 this is not florian's first time at lca 25 00:01:12,320 --> 00:01:16,159 but this is his first without suffering 26 00:01:14,640 --> 00:01:18,479 through jet lag 27 00:01:16,159 --> 00:01:20,400 um you can also get the slides for 28 00:01:18,479 --> 00:01:22,400 today's talk um which someone will pop 29 00:01:20,400 --> 00:01:24,880 into the chat um they have in-depth 30 00:01:22,400 --> 00:01:27,119 notes and some details that can go along 31 00:01:24,880 --> 00:01:29,600 with the talk today no my head am i 32 00:01:27,119 --> 00:01:29,600 florian 33 00:01:32,240 --> 00:01:37,840 thank you so this is my introduction to 34 00:01:35,439 --> 00:01:40,479 stereoscopic photography 35 00:01:37,840 --> 00:01:42,159 and videography and i do want to start 36 00:01:40,479 --> 00:01:44,560 this talk with an important note on 37 00:01:42,159 --> 00:01:46,159 accessibility so some of this talk does 38 00:01:44,560 --> 00:01:47,920 assume that you have functional vision 39 00:01:46,159 --> 00:01:50,159 in both eyes uh you will of course be 40 00:01:47,920 --> 00:01:51,680 able to see the images and the examples 41 00:01:50,159 --> 00:01:53,360 in this talk if you need to wear 42 00:01:51,680 --> 00:01:55,119 corrective lenses i certainly need to 43 00:01:53,360 --> 00:01:57,759 wear them too but if you do happen to 44 00:01:55,119 --> 00:01:59,360 have very bad vision or blindness in one 45 00:01:57,759 --> 00:02:01,360 eye then by the very nature of this 46 00:01:59,360 --> 00:02:03,040 topic there's some things that you won't 47 00:02:01,360 --> 00:02:04,079 be able to follow some examples that you 48 00:02:03,040 --> 00:02:06,159 won't be able to follow and i do 49 00:02:04,079 --> 00:02:07,200 apologize for that uh there's also a 50 00:02:06,159 --> 00:02:09,280 specific condition called 51 00:02:07,200 --> 00:02:11,360 stereoblindness which means that even 52 00:02:09,280 --> 00:02:12,959 though both your eyes are completely 53 00:02:11,360 --> 00:02:15,280 functional you're unable to perceive 54 00:02:12,959 --> 00:02:17,520 depth so if you have that condition then 55 00:02:15,280 --> 00:02:19,680 this talk might still be informative 56 00:02:17,520 --> 00:02:21,599 stereoblind people have seen this talk 57 00:02:19,680 --> 00:02:23,599 and then subsequently told me that they 58 00:02:21,599 --> 00:02:25,920 took away quite a bit from it it just 59 00:02:23,599 --> 00:02:28,480 might not be as immersive as it might be 60 00:02:25,920 --> 00:02:30,239 for people with stereo vision and 61 00:02:28,480 --> 00:02:32,480 likewise if you happen to have nystagmus 62 00:02:30,239 --> 00:02:34,959 or strabismus some of those limitations 63 00:02:32,480 --> 00:02:36,879 might also apply and possibly also if 64 00:02:34,959 --> 00:02:39,040 you're using an artificial lens implant 65 00:02:36,879 --> 00:02:41,440 which is common after cataract surgery 66 00:02:39,040 --> 00:02:43,920 again i do apologize for that uh in this 67 00:02:41,440 --> 00:02:45,280 case by the very nature of my topic 68 00:02:43,920 --> 00:02:48,480 there's unfortunately very little i can 69 00:02:45,280 --> 00:02:50,959 do to alleviate that however even if you 70 00:02:48,480 --> 00:02:52,560 yourself cannot see stereoscopic images 71 00:02:50,959 --> 00:02:54,480 and videos this talk does contain 72 00:02:52,560 --> 00:02:56,160 suggestions on how to make them which 73 00:02:54,480 --> 00:02:58,560 you can totally do even if you're making 74 00:02:56,160 --> 00:03:00,879 them for somebody else 75 00:02:58,560 --> 00:03:02,239 so with that said let's first get 76 00:03:00,879 --> 00:03:04,640 started with 77 00:03:02,239 --> 00:03:06,720 what stereoscopic vision or stereopsis 78 00:03:04,640 --> 00:03:09,200 as it's called really is 79 00:03:06,720 --> 00:03:11,440 and how it works so first of all what we 80 00:03:09,200 --> 00:03:13,840 need in order to visually perceive depth 81 00:03:11,440 --> 00:03:15,680 is two eyes and more specifically to 82 00:03:13,840 --> 00:03:17,519 forward-facing eyes so this is something 83 00:03:15,680 --> 00:03:19,519 that we humans have in common with say 84 00:03:17,519 --> 00:03:21,760 cats or foxes or owls 85 00:03:19,519 --> 00:03:24,239 that our eyes sit sort of on one side of 86 00:03:21,760 --> 00:03:25,840 the skull facing what we call forwards 87 00:03:24,239 --> 00:03:27,440 and they provide fields of view that 88 00:03:25,840 --> 00:03:29,200 overlap to a great extent and that of 89 00:03:27,440 --> 00:03:31,040 course comes at a cost namely the fact 90 00:03:29,200 --> 00:03:32,400 that our field of vision is relatively 91 00:03:31,040 --> 00:03:34,560 narrow so if you compare that for 92 00:03:32,400 --> 00:03:36,319 example to the field of vision of a 93 00:03:34,560 --> 00:03:39,040 horse where the eyes sit on the side of 94 00:03:36,319 --> 00:03:41,200 the skull the animal has almost 360 95 00:03:39,040 --> 00:03:43,280 degree vision only has a small blind 96 00:03:41,200 --> 00:03:45,440 spot directly to the rear of the skull 97 00:03:43,280 --> 00:03:47,840 and that's of course because a horse's 98 00:03:45,440 --> 00:03:50,720 evolutionary survival technique is 99 00:03:47,840 --> 00:03:52,640 flight so it's an herbivore and 100 00:03:50,720 --> 00:03:54,560 basically the sooner it can see a 101 00:03:52,640 --> 00:03:56,400 predator it can take flight and then it 102 00:03:54,560 --> 00:03:58,480 can live another day 103 00:03:56,400 --> 00:04:01,120 so it's kind of optimized for that 104 00:03:58,480 --> 00:04:03,120 we humans are predators ourselves and 105 00:04:01,120 --> 00:04:04,959 omnivores and we have evolved to sense 106 00:04:03,120 --> 00:04:07,920 depth and that of course greatly helps 107 00:04:04,959 --> 00:04:09,840 us in hunting particularly because we've 108 00:04:07,920 --> 00:04:11,920 also evolved brains that enabled us to 109 00:04:09,840 --> 00:04:14,400 make tools so if we make something like 110 00:04:11,920 --> 00:04:16,160 a spear or a lasso or a kylie or bow and 111 00:04:14,400 --> 00:04:18,239 arrow and we have an animal to throw or 112 00:04:16,160 --> 00:04:20,479 shoot it at then it greatly helps us to 113 00:04:18,239 --> 00:04:22,639 be able to sense intuitively but still 114 00:04:20,479 --> 00:04:24,560 pretty exactly how far that animal is 115 00:04:22,639 --> 00:04:26,880 away from us 116 00:04:24,560 --> 00:04:29,120 so how exactly does that work and what 117 00:04:26,880 --> 00:04:30,800 in our eyes and brains actually makes a 118 00:04:29,120 --> 00:04:32,960 sense depth 119 00:04:30,800 --> 00:04:34,960 and the first faculty that we need in 120 00:04:32,960 --> 00:04:38,160 order to perceive depth is the faculty 121 00:04:34,960 --> 00:04:41,680 of virgins so virgins is the ability to 122 00:04:38,160 --> 00:04:44,880 align the axes of our eyeballs so a line 123 00:04:41,680 --> 00:04:47,040 of sight as we call it um 124 00:04:44,880 --> 00:04:49,360 align them and essentially make them 125 00:04:47,040 --> 00:04:51,360 intersect pretty much arbitrarily in any 126 00:04:49,360 --> 00:04:53,280 point in space in front of us 127 00:04:51,360 --> 00:04:55,360 we might also be able to not make them 128 00:04:53,280 --> 00:04:58,160 intersect like when we stare aimlessly 129 00:04:55,360 --> 00:05:00,560 ahead but we can't really diverge our 130 00:04:58,160 --> 00:05:02,800 eyes but we can converge them almost 131 00:05:00,560 --> 00:05:04,960 arbitrarily and you can try that out 132 00:05:02,800 --> 00:05:06,880 most people will be able to stretch 133 00:05:04,960 --> 00:05:09,600 their arm out and then look at their 134 00:05:06,880 --> 00:05:11,759 fingertip and then bring the finger all 135 00:05:09,600 --> 00:05:14,160 the way in to the tip of the nose and 136 00:05:11,759 --> 00:05:15,759 still look at the fingertip while you're 137 00:05:14,160 --> 00:05:17,120 doing that and that might be very 138 00:05:15,759 --> 00:05:18,240 uncomfortable because it makes you very 139 00:05:17,120 --> 00:05:20,720 cross-eyed and you're not going to be 140 00:05:18,240 --> 00:05:23,199 able to hold that for very long but most 141 00:05:20,720 --> 00:05:24,880 people will be able to do that so we can 142 00:05:23,199 --> 00:05:27,600 converge our eyes 143 00:05:24,880 --> 00:05:30,000 almost arbitrarily 144 00:05:27,600 --> 00:05:32,160 to a very extreme degree 145 00:05:30,000 --> 00:05:33,600 and the second thing that we need is 146 00:05:32,160 --> 00:05:35,440 accommodation 147 00:05:33,600 --> 00:05:37,440 virgins gives us the ability to point 148 00:05:35,440 --> 00:05:38,800 both our eyes at one point in space and 149 00:05:37,440 --> 00:05:41,120 the other thing that we need for depth 150 00:05:38,800 --> 00:05:44,240 of vision is accommodation which is the 151 00:05:41,120 --> 00:05:46,240 ability to either stretch or to relax 152 00:05:44,240 --> 00:05:48,080 the elastic lens in our eyes or the 153 00:05:46,240 --> 00:05:49,840 thing that sits right behind our pupil 154 00:05:48,080 --> 00:05:52,000 and do that in such a way that there's a 155 00:05:49,840 --> 00:05:54,240 specific point in space or a specific 156 00:05:52,000 --> 00:05:55,919 plane in front of us that produces a 157 00:05:54,240 --> 00:05:56,880 sharp image on our retina in the back of 158 00:05:55,919 --> 00:05:58,319 the eye 159 00:05:56,880 --> 00:06:01,919 and commonly 160 00:05:58,319 --> 00:06:04,240 the point where we verge and the plane 161 00:06:01,919 --> 00:06:06,720 where we accommodate those intersect so 162 00:06:04,240 --> 00:06:09,520 we're kind of looking at the same 163 00:06:06,720 --> 00:06:11,919 spot in space in front of us using both 164 00:06:09,520 --> 00:06:15,600 of those things but we don't have to do 165 00:06:11,919 --> 00:06:18,080 that and we'll get to that in a second 166 00:06:15,600 --> 00:06:20,479 but what that means is when we are 167 00:06:18,080 --> 00:06:23,039 looking at something our eyes 168 00:06:20,479 --> 00:06:25,360 fundamentally produce two images and 169 00:06:23,039 --> 00:06:28,000 these two images are pretty much exactly 170 00:06:25,360 --> 00:06:29,840 identical in one spot so the thing that 171 00:06:28,000 --> 00:06:31,440 the spot that we verge on 172 00:06:29,840 --> 00:06:33,680 and then they are slightly different 173 00:06:31,440 --> 00:06:36,000 anywhere outside that spot 174 00:06:33,680 --> 00:06:38,880 and this is what we call binocular 175 00:06:36,000 --> 00:06:40,800 disparity and through what has to be an 176 00:06:38,880 --> 00:06:43,280 inordinate amount of 177 00:06:40,800 --> 00:06:46,560 trial and error and face plant 178 00:06:43,280 --> 00:06:49,599 in our infancy what our brain learns is 179 00:06:46,560 --> 00:06:52,479 to interpret these disparities between 180 00:06:49,599 --> 00:06:53,840 the two optical inputs as cues about 181 00:06:52,479 --> 00:06:55,680 depth 182 00:06:53,840 --> 00:06:58,000 and it's by these differences that our 183 00:06:55,680 --> 00:07:00,800 brain essentially builds a depth map of 184 00:06:58,000 --> 00:07:01,680 our surroundings 185 00:07:00,800 --> 00:07:03,360 so 186 00:07:01,680 --> 00:07:06,160 now that we know how real depth 187 00:07:03,360 --> 00:07:08,880 perception works meaning how our eyes 188 00:07:06,160 --> 00:07:10,880 signal to our brains that an object is 189 00:07:08,880 --> 00:07:13,120 at a greater or a lesser distance from 190 00:07:10,880 --> 00:07:14,319 us we can talk about how we can trick 191 00:07:13,120 --> 00:07:17,360 our brain 192 00:07:14,319 --> 00:07:18,400 into seeing depth when objectively there 193 00:07:17,360 --> 00:07:20,000 is none 194 00:07:18,400 --> 00:07:22,000 so taking two 195 00:07:20,000 --> 00:07:23,520 two-dimensional images and then making 196 00:07:22,000 --> 00:07:26,479 our brains conjure up a 197 00:07:23,520 --> 00:07:28,800 three-dimensional image from that 198 00:07:26,479 --> 00:07:31,680 so for example 199 00:07:28,800 --> 00:07:34,479 i've got two two-dimensional images here 200 00:07:31,680 --> 00:07:36,479 um and this one might correspond to what 201 00:07:34,479 --> 00:07:39,039 your left eye sees and this one 202 00:07:36,479 --> 00:07:40,639 corresponds to what your right eye sees 203 00:07:39,039 --> 00:07:42,400 so here's an example of such an image 204 00:07:40,639 --> 00:07:43,840 don't worry for now about how we make 205 00:07:42,400 --> 00:07:45,599 those and how we make that happen we'll 206 00:07:43,840 --> 00:07:46,960 get to that in a jiffy but 207 00:07:45,599 --> 00:07:50,639 the next thing that we need to talk 208 00:07:46,960 --> 00:07:52,720 about is stereoscopic projection and 209 00:07:50,639 --> 00:07:54,800 stereoscopic projection is about making 210 00:07:52,720 --> 00:07:57,199 your left eye see only the left eye 211 00:07:54,800 --> 00:07:58,960 image and making the right eye see only 212 00:07:57,199 --> 00:08:00,879 the right eye image so that your brain 213 00:07:58,960 --> 00:08:02,639 then puts everything together for an 214 00:08:00,879 --> 00:08:05,039 illusion of depth 215 00:08:02,639 --> 00:08:07,280 and there's multiple ways of doing that 216 00:08:05,039 --> 00:08:10,639 so i'll start with something very low 217 00:08:07,280 --> 00:08:12,639 tech a stereoscopic viewer or simply a 218 00:08:10,639 --> 00:08:15,120 stereoscope i happen to have one here 219 00:08:12,639 --> 00:08:16,639 let me swiftly explain how this works 220 00:08:15,120 --> 00:08:18,720 there is a 221 00:08:16,639 --> 00:08:21,039 little slider here and then you take a 222 00:08:18,720 --> 00:08:23,039 print of a stereoscopic image that you 223 00:08:21,039 --> 00:08:24,879 put in here you close the device so that 224 00:08:23,039 --> 00:08:26,560 the print is jammed in place and can't 225 00:08:24,879 --> 00:08:28,639 move about you bring the whole thing up 226 00:08:26,560 --> 00:08:30,720 to your face and then you can look 227 00:08:28,639 --> 00:08:32,159 through the eyepieces 228 00:08:30,720 --> 00:08:33,440 and there's something important that 229 00:08:32,159 --> 00:08:35,919 you'll see if you look at this little 230 00:08:33,440 --> 00:08:38,320 device from this angle which is there's 231 00:08:35,919 --> 00:08:40,240 a little black separator 232 00:08:38,320 --> 00:08:42,320 let's see here right there's a little 233 00:08:40,240 --> 00:08:43,919 black separator and it ensures that my 234 00:08:42,320 --> 00:08:45,920 left eye can't peek over at the right 235 00:08:43,919 --> 00:08:49,120 eye image and my right eye can't catch a 236 00:08:45,920 --> 00:08:51,040 glimpse of the left eye image this by 237 00:08:49,120 --> 00:08:52,959 the way is called a brewster type 238 00:08:51,040 --> 00:08:54,720 lenticular stereoscope 239 00:08:52,959 --> 00:08:57,200 and this was popularized by a chap named 240 00:08:54,720 --> 00:08:58,880 david brewster in 1849 so it's about 180 241 00:08:57,200 --> 00:09:00,880 years old 242 00:08:58,880 --> 00:09:03,440 um 243 00:09:00,880 --> 00:09:04,720 so that's a very low-tech device here a 244 00:09:03,440 --> 00:09:06,800 slightly more high-tech is a 245 00:09:04,720 --> 00:09:09,519 stereoscopic projector now stereoscopic 246 00:09:06,800 --> 00:09:11,200 projectors came along for slides in the 247 00:09:09,519 --> 00:09:13,920 1950s 60s 248 00:09:11,200 --> 00:09:16,320 so the principle is this you've got uh 249 00:09:13,920 --> 00:09:17,519 you've got a magazine of left eye images 250 00:09:16,320 --> 00:09:20,080 you've got a magazine of right eye 251 00:09:17,519 --> 00:09:22,880 images you put them into this projector 252 00:09:20,080 --> 00:09:24,959 and they get projected out uh via two 253 00:09:22,880 --> 00:09:27,279 different lamps two different projectors 254 00:09:24,959 --> 00:09:29,760 and they are polarized the light damage 255 00:09:27,279 --> 00:09:32,640 is polarized oppositely and then you 256 00:09:29,760 --> 00:09:34,160 wear goggles so that the 257 00:09:32,640 --> 00:09:36,399 stuff that is for your right eye that's 258 00:09:34,160 --> 00:09:38,880 polarized one way is hidden from your 259 00:09:36,399 --> 00:09:40,240 left eye and the thing that's polarized 260 00:09:38,880 --> 00:09:42,000 the other way 261 00:09:40,240 --> 00:09:43,680 that's for your right eye is hidden from 262 00:09:42,000 --> 00:09:45,440 your left eye 263 00:09:43,680 --> 00:09:47,040 and there are of course digital versions 264 00:09:45,440 --> 00:09:48,240 of this as well they're available to 265 00:09:47,040 --> 00:09:51,120 this day 266 00:09:48,240 --> 00:09:53,279 there's also 3d tv which is a similar uh 267 00:09:51,120 --> 00:09:55,200 concept except that you're not using two 268 00:09:53,279 --> 00:09:57,200 projectors but you're using a tv screen 269 00:09:55,200 --> 00:10:01,200 you've got one row of pixels 270 00:09:57,200 --> 00:10:03,839 that um or one line of pixels that 271 00:10:01,200 --> 00:10:06,079 emits light polarized one way and then 272 00:10:03,839 --> 00:10:07,600 the next line the next row 273 00:10:06,079 --> 00:10:09,200 emits light polarized the other way and 274 00:10:07,600 --> 00:10:11,200 then you wear goggles and then that 275 00:10:09,200 --> 00:10:12,720 picks everything apart again but that 276 00:10:11,200 --> 00:10:14,480 too has a downside just as with the 277 00:10:12,720 --> 00:10:16,240 polarized light projectors it's pretty 278 00:10:14,480 --> 00:10:17,839 involved on the technology and logistics 279 00:10:16,240 --> 00:10:19,040 side right you might need projectors you 280 00:10:17,839 --> 00:10:19,920 might need a silver screen because you 281 00:10:19,040 --> 00:10:21,920 can't 282 00:10:19,920 --> 00:10:23,360 project polarized light onto a white 283 00:10:21,920 --> 00:10:24,800 wall that doesn't work it messes up the 284 00:10:23,360 --> 00:10:26,560 polarization on reflection you might 285 00:10:24,800 --> 00:10:28,320 need a big screen tv your audience needs 286 00:10:26,560 --> 00:10:29,839 goggles etc it's all very much 287 00:10:28,320 --> 00:10:32,160 non-trivial 288 00:10:29,839 --> 00:10:33,839 but what if instead we could employ a 289 00:10:32,160 --> 00:10:35,760 technique that requires none of that no 290 00:10:33,839 --> 00:10:37,440 special projection equipment no goggles 291 00:10:35,760 --> 00:10:40,160 no nothing where you can literally hang 292 00:10:37,440 --> 00:10:41,680 your stereo photography in a gallery and 293 00:10:40,160 --> 00:10:43,839 visitors could just scroll through and 294 00:10:41,680 --> 00:10:46,560 look at your images and see them in full 295 00:10:43,839 --> 00:10:48,240 depth and such a technique does exist 296 00:10:46,560 --> 00:10:49,839 and we're going to focus on it for the 297 00:10:48,240 --> 00:10:53,120 rest of the talk and it's called free 298 00:10:49,839 --> 00:10:55,680 viewing and it comes in two flavors 299 00:10:53,120 --> 00:10:58,480 now freebie in general means that we can 300 00:10:55,680 --> 00:11:01,200 take two stereoscopic images and we look 301 00:10:58,480 --> 00:11:03,680 at them using a certain technique that 302 00:11:01,200 --> 00:11:05,760 requires no stereoscope no projector 303 00:11:03,680 --> 00:11:07,760 nothing all that you do need is two 304 00:11:05,760 --> 00:11:09,519 functioning eyes and like i said they're 305 00:11:07,760 --> 00:11:11,120 two flavors of free viewing and there's 306 00:11:09,519 --> 00:11:13,360 one that's easy to explain and 307 00:11:11,120 --> 00:11:14,800 understand but somewhat difficult to do 308 00:11:13,360 --> 00:11:16,880 and there's another one that's a bit 309 00:11:14,800 --> 00:11:18,160 more complex to explain and comprehend 310 00:11:16,880 --> 00:11:19,680 but easier to do at least for most 311 00:11:18,160 --> 00:11:21,279 people and i'll start with the one 312 00:11:19,680 --> 00:11:23,920 that's easier to explain and then we'll 313 00:11:21,279 --> 00:11:27,040 move on to the one that's easier to do 314 00:11:23,920 --> 00:11:28,800 so the first one is called wall eyed 315 00:11:27,040 --> 00:11:30,480 free viewing warlike stereoscopic free 316 00:11:28,800 --> 00:11:34,560 viewing or sometimes called parallel 317 00:11:30,480 --> 00:11:36,720 view so what i have here is a print of a 318 00:11:34,560 --> 00:11:38,160 stereogram so it's the same image as the 319 00:11:36,720 --> 00:11:39,440 one that i showed you earlier that 320 00:11:38,160 --> 00:11:42,000 jammed into my stereoscope it's just 321 00:11:39,440 --> 00:11:43,760 blown up a bit right again the left eye 322 00:11:42,000 --> 00:11:45,120 images on the left the right the left 323 00:11:43,760 --> 00:11:46,560 images on the left the right are images 324 00:11:45,120 --> 00:11:47,680 on the right 325 00:11:46,560 --> 00:11:49,839 so 326 00:11:47,680 --> 00:11:51,519 if you were if i were to hold this up in 327 00:11:49,839 --> 00:11:53,680 front of you and you were just looking 328 00:11:51,519 --> 00:11:54,720 at this thing then normally what you 329 00:11:53,680 --> 00:11:57,920 would do 330 00:11:54,720 --> 00:12:00,720 is this your versions and accommodation 331 00:11:57,920 --> 00:12:03,120 points would sit right on the surface of 332 00:12:00,720 --> 00:12:05,120 the print so in this graphic here the 333 00:12:03,120 --> 00:12:06,639 dashed line is the surface so that would 334 00:12:05,120 --> 00:12:08,320 be the surface of the 335 00:12:06,639 --> 00:12:10,880 of the photo that we're looking at the 336 00:12:08,320 --> 00:12:12,240 dots are eyes the converging lines are 337 00:12:10,880 --> 00:12:14,720 the lines of sight that meet at my 338 00:12:12,240 --> 00:12:17,360 virgins point and the arrow represents 339 00:12:14,720 --> 00:12:19,680 my accommodation so that is the plane 340 00:12:17,360 --> 00:12:20,480 whose distance i set my eyes to 341 00:12:19,680 --> 00:12:23,600 so 342 00:12:20,480 --> 00:12:25,440 if i were to uh look at this thing or if 343 00:12:23,600 --> 00:12:27,600 you were to look at this thing it would 344 00:12:25,440 --> 00:12:29,040 look like this that's what your eyes do 345 00:12:27,600 --> 00:12:31,120 naturally 346 00:12:29,040 --> 00:12:34,079 but they don't have to 347 00:12:31,120 --> 00:12:36,720 because what you can also do 348 00:12:34,079 --> 00:12:38,800 is you can 349 00:12:36,720 --> 00:12:39,839 instead of looking at the surface of the 350 00:12:38,800 --> 00:12:42,560 print 351 00:12:39,839 --> 00:12:44,320 you can look at an imaginary spot behind 352 00:12:42,560 --> 00:12:45,760 the print 353 00:12:44,320 --> 00:12:47,600 or whatever surface it is that we're 354 00:12:45,760 --> 00:12:49,760 looking at just an imaginary spot behind 355 00:12:47,600 --> 00:12:51,200 that surface while maintaining your 356 00:12:49,760 --> 00:12:52,880 accommodation 357 00:12:51,200 --> 00:12:56,000 as it was before 358 00:12:52,880 --> 00:12:58,399 and if you do it just right then what's 359 00:12:56,000 --> 00:13:00,800 going to end up happening is your left 360 00:12:58,399 --> 00:13:02,399 eye looks just at the left eye image and 361 00:13:00,800 --> 00:13:04,959 your right eye looks just at the right 362 00:13:02,399 --> 00:13:07,440 eye image and then what you see is one 363 00:13:04,959 --> 00:13:09,040 image that overlaps that's made from 364 00:13:07,440 --> 00:13:11,040 both the source images and that 365 00:13:09,040 --> 00:13:13,360 magically has depth 366 00:13:11,040 --> 00:13:15,600 and i have an example up for you next so 367 00:13:13,360 --> 00:13:16,560 you can try this out 368 00:13:15,600 --> 00:13:17,920 so 369 00:13:16,560 --> 00:13:20,480 i don't know if you're watching this on 370 00:13:17,920 --> 00:13:23,040 a full-size monitor or a laptop screen 371 00:13:20,480 --> 00:13:24,399 or a big-screen tv or your phone so you 372 00:13:23,040 --> 00:13:25,600 may have to play with the distance 373 00:13:24,399 --> 00:13:27,600 between your screen and your eyes a 374 00:13:25,600 --> 00:13:30,079 little bit but the principle is in 375 00:13:27,600 --> 00:13:32,639 general the same what you want to do is 376 00:13:30,079 --> 00:13:34,800 you want to look over the top edge of 377 00:13:32,639 --> 00:13:36,560 the screen at a spot in the distance say 378 00:13:34,800 --> 00:13:37,839 a spot on the wall picture on the wall 379 00:13:36,560 --> 00:13:39,360 or something like that 380 00:13:37,839 --> 00:13:41,920 and that what you want to do is you want 381 00:13:39,360 --> 00:13:44,320 to try coming down just a little bit 382 00:13:41,920 --> 00:13:46,000 with your eyes so that you look at the 383 00:13:44,320 --> 00:13:48,160 actual image 384 00:13:46,000 --> 00:13:50,639 and not change the spot that you're 385 00:13:48,160 --> 00:13:52,560 looking at in the process 386 00:13:50,639 --> 00:13:54,880 and then what's going to happen is that 387 00:13:52,560 --> 00:13:57,120 the left eye image is going to be right 388 00:13:54,880 --> 00:13:58,800 in the line of sight of your left eye 389 00:13:57,120 --> 00:14:01,040 and your right eye image is going to be 390 00:13:58,800 --> 00:14:04,000 right in the line of sight of your right 391 00:14:01,040 --> 00:14:06,480 eye and what's then going to happen is 392 00:14:04,000 --> 00:14:09,279 that rather than seeing these two images 393 00:14:06,480 --> 00:14:12,160 you'll actually end up seeing three 394 00:14:09,279 --> 00:14:14,639 a left one that's blurry a right one 395 00:14:12,160 --> 00:14:16,639 that's blurry and then a center one 396 00:14:14,639 --> 00:14:17,600 from the other two overlapping that's 397 00:14:16,639 --> 00:14:19,519 sharp 398 00:14:17,600 --> 00:14:20,880 and that magically has 399 00:14:19,519 --> 00:14:22,880 depth 400 00:14:20,880 --> 00:14:24,560 so if you're not watching this live if 401 00:14:22,880 --> 00:14:27,519 you're watching this on the recording 402 00:14:24,560 --> 00:14:29,680 then now might be a good time to pause 403 00:14:27,519 --> 00:14:30,800 the playback and perhaps give this a few 404 00:14:29,680 --> 00:14:33,120 tries 405 00:14:30,800 --> 00:14:34,079 for now i leave it up for a few more 406 00:14:33,120 --> 00:14:36,399 seconds 407 00:14:34,079 --> 00:14:38,959 you can simply try that out again 408 00:14:36,399 --> 00:14:41,040 spot on the wall behind the picture 409 00:14:38,959 --> 00:14:42,639 bring your eyes down so you look at the 410 00:14:41,040 --> 00:14:45,760 picture and try 411 00:14:42,639 --> 00:14:47,600 not to look anywhere but 412 00:14:45,760 --> 00:14:48,399 distance wise but where you were staring 413 00:14:47,600 --> 00:14:50,399 at 414 00:14:48,399 --> 00:14:51,360 before 415 00:14:50,399 --> 00:14:53,680 but 416 00:14:51,360 --> 00:14:55,600 if this doesn't work for you 417 00:14:53,680 --> 00:14:57,839 please do not fret 418 00:14:55,600 --> 00:14:58,880 like i said this is the more difficult 419 00:14:57,839 --> 00:15:01,360 method 420 00:14:58,880 --> 00:15:03,120 and this is the one that actually 421 00:15:01,360 --> 00:15:04,639 is 422 00:15:03,120 --> 00:15:05,680 works for fewer people let's put it that 423 00:15:04,639 --> 00:15:07,680 way 424 00:15:05,680 --> 00:15:09,760 and i'll get to the one that's easier 425 00:15:07,680 --> 00:15:12,480 for most people including myself 426 00:15:09,760 --> 00:15:15,040 actually next 427 00:15:12,480 --> 00:15:17,040 all right so if any of you have managed 428 00:15:15,040 --> 00:15:18,639 to do this congratulations 429 00:15:17,040 --> 00:15:20,720 we'll move on now 430 00:15:18,639 --> 00:15:23,519 because the next um 431 00:15:20,720 --> 00:15:26,399 option that you have is cross-eyed 432 00:15:23,519 --> 00:15:28,399 stereoscopic free viewing or cross view 433 00:15:26,399 --> 00:15:29,600 so here's how that works 434 00:15:28,399 --> 00:15:31,519 what you do 435 00:15:29,600 --> 00:15:33,839 is and you're probably already guessing 436 00:15:31,519 --> 00:15:36,480 that right in a wall-eyed image so 437 00:15:33,839 --> 00:15:38,079 parallel view our virgin's point is 438 00:15:36,480 --> 00:15:39,360 behind the print 439 00:15:38,079 --> 00:15:42,079 while we're maintaining our 440 00:15:39,360 --> 00:15:44,000 accommodation on the plane of the print 441 00:15:42,079 --> 00:15:46,320 or the plane of the surface 442 00:15:44,000 --> 00:15:49,279 in a cross-eyed image it's in front of 443 00:15:46,320 --> 00:15:50,399 the print so graphically it looks like 444 00:15:49,279 --> 00:15:52,000 this 445 00:15:50,399 --> 00:15:52,800 and what that means of course is that 446 00:15:52,000 --> 00:15:53,680 now 447 00:15:52,800 --> 00:15:57,279 your 448 00:15:53,680 --> 00:15:59,680 right eye looks at the image on the left 449 00:15:57,279 --> 00:16:01,440 your left eye looks at the image on the 450 00:15:59,680 --> 00:16:03,759 right so 451 00:16:01,440 --> 00:16:06,560 a cross view stereoscopic image is 452 00:16:03,759 --> 00:16:10,000 actually reversed so camera takes these 453 00:16:06,560 --> 00:16:11,440 pictures and then you reverse them 454 00:16:10,000 --> 00:16:13,600 and the interesting bit about this is 455 00:16:11,440 --> 00:16:15,600 that this is easier for most people to 456 00:16:13,600 --> 00:16:17,759 voluntarily do i don't really know why 457 00:16:15,600 --> 00:16:19,519 but it's certainly true for myself as 458 00:16:17,759 --> 00:16:21,440 well so what you want to do if you 459 00:16:19,519 --> 00:16:23,440 haven't done this before on the next 460 00:16:21,440 --> 00:16:24,959 image is you want to cross your eyes 461 00:16:23,440 --> 00:16:26,320 really hard 462 00:16:24,959 --> 00:16:27,839 means you're totally overdoing it but 463 00:16:26,320 --> 00:16:29,279 that's totally okay 464 00:16:27,839 --> 00:16:30,880 and then you want to let your eyes 465 00:16:29,279 --> 00:16:33,120 settle back to normal 466 00:16:30,880 --> 00:16:35,839 and chances are that what's going to 467 00:16:33,120 --> 00:16:37,279 happen is by the time your eyes cross 468 00:16:35,839 --> 00:16:38,639 just to the point where everything falls 469 00:16:37,279 --> 00:16:40,720 into place you get such a strong 470 00:16:38,639 --> 00:16:42,800 stimulus in your brain that your brain 471 00:16:40,720 --> 00:16:45,199 really doesn't want to let go and then 472 00:16:42,800 --> 00:16:47,440 you see the depth image 473 00:16:45,199 --> 00:16:49,360 so here like i said for most people the 474 00:16:47,440 --> 00:16:50,959 next image will actually be easier than 475 00:16:49,360 --> 00:16:54,320 the one that i just showed you it's 476 00:16:50,959 --> 00:16:56,959 exactly the same motif it's just 477 00:16:54,320 --> 00:16:59,199 the sides are reversed right and again 478 00:16:56,959 --> 00:17:01,680 if you're watching this on a recording 479 00:16:59,199 --> 00:17:04,559 feel free to pause the stream here pause 480 00:17:01,680 --> 00:17:06,799 the playback and try this a few times 481 00:17:04,559 --> 00:17:10,000 until you get the hang of it most people 482 00:17:06,799 --> 00:17:11,600 will be able to do this 483 00:17:10,000 --> 00:17:13,600 and by the way when you initially try 484 00:17:11,600 --> 00:17:15,199 this it might actually help that you're 485 00:17:13,600 --> 00:17:17,679 using an image that's relatively large 486 00:17:15,199 --> 00:17:19,120 so it covers a rather large fraction of 487 00:17:17,679 --> 00:17:20,400 your field of vision once you get the 488 00:17:19,120 --> 00:17:22,000 hang of it doesn't matter once you get 489 00:17:20,400 --> 00:17:24,480 the hang of it you can do cross view on 490 00:17:22,000 --> 00:17:26,000 an image that's this tiny no problem but 491 00:17:24,480 --> 00:17:28,319 for learning it it's probably a good 492 00:17:26,000 --> 00:17:30,640 idea to start with a big image so again 493 00:17:28,319 --> 00:17:33,919 what you want to do is you want to stare 494 00:17:30,640 --> 00:17:36,640 at this image cross your eyes and then 495 00:17:33,919 --> 00:17:39,520 let your eyes come back to normal 496 00:17:36,640 --> 00:17:41,679 and at some point if you're lucky 497 00:17:39,520 --> 00:17:43,280 things are going to click into place 498 00:17:41,679 --> 00:17:44,480 again most people can't do this on the 499 00:17:43,280 --> 00:17:47,039 first try 500 00:17:44,480 --> 00:17:48,880 but if you give it a little time 501 00:17:47,039 --> 00:17:50,400 and i'll actually shut up for a few 502 00:17:48,880 --> 00:17:52,720 seconds now 503 00:17:50,400 --> 00:17:57,480 so that you can try this out most people 504 00:17:52,720 --> 00:17:57,480 will eventually succeed at this 505 00:18:04,880 --> 00:18:10,880 and just in case i'm making the av team 506 00:18:06,720 --> 00:18:10,880 nervous yes i'm still here it's all good 507 00:18:11,919 --> 00:18:15,679 and if you actually manage to get the 508 00:18:13,840 --> 00:18:17,520 depth effect what's going to happen 509 00:18:15,679 --> 00:18:19,280 relatively quickly is you're going to be 510 00:18:17,520 --> 00:18:21,120 able to see 511 00:18:19,280 --> 00:18:24,160 the relative depth of 512 00:18:21,120 --> 00:18:26,960 say these trim boxwood bushes uh you're 513 00:18:24,160 --> 00:18:29,280 going to see what the distance is to the 514 00:18:26,960 --> 00:18:31,360 various people in the image you're going 515 00:18:29,280 --> 00:18:33,120 to be able to see the depth of the 516 00:18:31,360 --> 00:18:35,200 stairs you're going to be able to see 517 00:18:33,120 --> 00:18:37,120 the depth of the columns 518 00:18:35,200 --> 00:18:38,960 you're also going to be able to see how 519 00:18:37,120 --> 00:18:41,840 far the ridge line or actually the two 520 00:18:38,960 --> 00:18:43,600 ridge lines are that are behind the 521 00:18:41,840 --> 00:18:45,039 building 522 00:18:43,600 --> 00:18:46,640 and uh 523 00:18:45,039 --> 00:18:48,640 if any of you manage this now i'm 524 00:18:46,640 --> 00:18:50,480 unfortunately i'm unable to look into 525 00:18:48,640 --> 00:18:52,720 the chat right now but i'm really really 526 00:18:50,480 --> 00:18:55,039 hoping that some of you um succeeded 527 00:18:52,720 --> 00:18:58,000 this because when it works it's 528 00:18:55,039 --> 00:19:00,000 uh it's it's uh it's it's a really sort 529 00:18:58,000 --> 00:19:02,720 of satisfying feeling 530 00:19:00,000 --> 00:19:04,960 so of course i'm not going to assume 531 00:19:02,720 --> 00:19:06,960 that you're watching this through a 3d 532 00:19:04,960 --> 00:19:09,440 projector and i also cannot assume that 533 00:19:06,960 --> 00:19:11,360 you have a stereoscope at hand so from 534 00:19:09,440 --> 00:19:13,919 now on for the rest of this talk i'm 535 00:19:11,360 --> 00:19:15,200 going to default to free viewing and i'm 536 00:19:13,919 --> 00:19:17,440 going to default to cross site 537 00:19:15,200 --> 00:19:19,760 previewing specifically 538 00:19:17,440 --> 00:19:21,520 so now that we've seen 539 00:19:19,760 --> 00:19:24,240 what stereograms are and we've hopefully 540 00:19:21,520 --> 00:19:27,280 learned how we look at them let's talk 541 00:19:24,240 --> 00:19:29,440 about how we make them 542 00:19:27,280 --> 00:19:31,919 and as you can imagine there are 543 00:19:29,440 --> 00:19:33,840 multiple ways of doing that so 544 00:19:31,919 --> 00:19:36,880 the first thing that i guess a lot of 545 00:19:33,840 --> 00:19:38,880 you might think of is well maybe i need 546 00:19:36,880 --> 00:19:40,480 to put a special lens on my camera and 547 00:19:38,880 --> 00:19:44,080 such a thing totally exists so there are 548 00:19:40,480 --> 00:19:45,520 stereoscopic lenses so for example um 549 00:19:44,080 --> 00:19:48,000 the next one that i'm showing here this 550 00:19:45,520 --> 00:19:49,919 happens to be a discontinued product but 551 00:19:48,000 --> 00:19:52,480 this is a stereoscopic lens that you can 552 00:19:49,919 --> 00:19:53,840 just put on a camera so you use it like 553 00:19:52,480 --> 00:19:56,080 any other prime lens so you can do 554 00:19:53,840 --> 00:19:58,000 autofocus auto exposure and whatnot and 555 00:19:56,080 --> 00:19:59,280 it will create two stereoscopic images 556 00:19:58,000 --> 00:20:01,200 in one frame 557 00:19:59,280 --> 00:20:03,840 but if you look at this you will also 558 00:20:01,200 --> 00:20:06,480 quickly realize this has a flaw 559 00:20:03,840 --> 00:20:08,720 which is that the two lenses 560 00:20:06,480 --> 00:20:11,200 are extremely close together they're 561 00:20:08,720 --> 00:20:13,520 much closer together than human eyes so 562 00:20:11,200 --> 00:20:16,400 that means this will make the pictures 563 00:20:13,520 --> 00:20:19,200 heavily hypostereoscopic 564 00:20:16,400 --> 00:20:21,840 so hypostereoscopic is 565 00:20:19,200 --> 00:20:23,679 when the stereoscopic distance that is 566 00:20:21,840 --> 00:20:25,679 to say the distance between the two 567 00:20:23,679 --> 00:20:28,720 lenses or the two spots in space where 568 00:20:25,679 --> 00:20:30,960 we took the images is a lot less than 569 00:20:28,720 --> 00:20:32,320 the image between your pupils so the 570 00:20:30,960 --> 00:20:33,760 distance between your i'm sorry the 571 00:20:32,320 --> 00:20:35,039 distance between your pupils the 572 00:20:33,760 --> 00:20:37,600 distance between your pupils is 573 00:20:35,039 --> 00:20:39,120 approximately 70 millimeters and in this 574 00:20:37,600 --> 00:20:40,880 case the lens has a stereoscopic 575 00:20:39,120 --> 00:20:43,039 distance of maybe 10 millimeters and 576 00:20:40,880 --> 00:20:46,640 what that means is that the stereoscopic 577 00:20:43,039 --> 00:20:49,520 effect that you're getting from these is 578 00:20:46,640 --> 00:20:51,520 a lot less pronounced you you'll get a 579 00:20:49,520 --> 00:20:54,799 lot less 580 00:20:51,520 --> 00:20:56,240 depth than you'd perhaps expect this 581 00:20:54,799 --> 00:20:59,120 sort of lens is still interesting for 582 00:20:56,240 --> 00:21:00,480 doing uh macro stereo photography so you 583 00:20:59,120 --> 00:21:02,159 combine this with a macro ring for 584 00:21:00,480 --> 00:21:04,159 example and that can produce really 585 00:21:02,159 --> 00:21:07,280 really interesting results so for 586 00:21:04,159 --> 00:21:09,760 example i've taken macro stereo shots of 587 00:21:07,280 --> 00:21:13,200 tiny shells and that's very interesting 588 00:21:09,760 --> 00:21:15,840 but sort of for general purpose use 589 00:21:13,200 --> 00:21:19,200 this doesn't really work too well 590 00:21:15,840 --> 00:21:20,559 but there's uh the next step which is 591 00:21:19,200 --> 00:21:22,080 this thing here i actually have a prop 592 00:21:20,559 --> 00:21:23,440 of this because i happen to own this 593 00:21:22,080 --> 00:21:27,520 thing so it looks like this when it's 594 00:21:23,440 --> 00:21:30,400 when it's attached to a camera right um 595 00:21:27,520 --> 00:21:32,880 and this thing as you can see now that 596 00:21:30,400 --> 00:21:37,360 has if i hold it up to my face that has 597 00:21:32,880 --> 00:21:39,840 roughly the same distance as my eyes 598 00:21:37,360 --> 00:21:41,840 and um this is something that we call 599 00:21:39,840 --> 00:21:43,600 iso stereoscopic or roughly 600 00:21:41,840 --> 00:21:46,400 isosteroscopic 601 00:21:43,600 --> 00:21:48,320 so this thing here has a roughly 90 602 00:21:46,400 --> 00:21:51,200 millimeter distance stereoscopic 603 00:21:48,320 --> 00:21:53,200 distance um and that compares relatively 604 00:21:51,200 --> 00:21:56,640 well to the typical 70 millimeters that 605 00:21:53,200 --> 00:21:59,039 you have from from your eyes so 606 00:21:56,640 --> 00:22:00,559 pictures that you take with this sort of 607 00:21:59,039 --> 00:22:02,640 uh lens 608 00:22:00,559 --> 00:22:04,640 the depth effect will roughly match your 609 00:22:02,640 --> 00:22:05,919 natural stereo distance 610 00:22:04,640 --> 00:22:08,880 and then there's one other thing that 611 00:22:05,919 --> 00:22:10,880 you can use and uh those are 612 00:22:08,880 --> 00:22:12,559 mirror lens attachments 613 00:22:10,880 --> 00:22:14,559 so for example this thing this is called 614 00:22:12,559 --> 00:22:16,559 the cooler deeper 615 00:22:14,559 --> 00:22:17,760 and this is something it works through 616 00:22:16,559 --> 00:22:19,520 an arrangement of several mirrors 617 00:22:17,760 --> 00:22:22,000 they're all at 45 degree angles to the 618 00:22:19,520 --> 00:22:24,080 plane of the sensor so the light path is 619 00:22:22,000 --> 00:22:27,440 effectively deflected twice it's kind of 620 00:22:24,080 --> 00:22:30,240 like this this shape and um 621 00:22:27,440 --> 00:22:31,840 it offsets the light hitting uh the left 622 00:22:30,240 --> 00:22:33,600 half of your sense a little further to 623 00:22:31,840 --> 00:22:34,720 the left and offsets the light hitting 624 00:22:33,600 --> 00:22:37,679 the right half of your sensor a little 625 00:22:34,720 --> 00:22:40,640 further to the right and so that makes 626 00:22:37,679 --> 00:22:43,039 this device slightly hyper stereoscopic 627 00:22:40,640 --> 00:22:45,280 so if we have a stereoscopic distance 628 00:22:43,039 --> 00:22:47,520 that's larger than 629 00:22:45,280 --> 00:22:49,840 the distance between our pupils we call 630 00:22:47,520 --> 00:22:52,960 that hyper stereoscopic so in this case 631 00:22:49,840 --> 00:22:56,559 it's about 105 millimeters this by the 632 00:22:52,960 --> 00:22:58,080 way is really a design that's made for 633 00:22:56,559 --> 00:23:01,760 sort of full-frame 634 00:22:58,080 --> 00:23:04,320 dslrs uh it also has like another 635 00:23:01,760 --> 00:23:06,159 small version that you can clip onto 636 00:23:04,320 --> 00:23:09,200 your phone but this thing is very much 637 00:23:06,159 --> 00:23:12,080 made for sort of big dslrs 638 00:23:09,200 --> 00:23:14,640 but just like i can scarcely expect you 639 00:23:12,080 --> 00:23:17,039 to have a stereoscope in your possession 640 00:23:14,640 --> 00:23:19,120 or a stereoscopic polarized light 641 00:23:17,039 --> 00:23:22,000 projector i can scarcely expect you to 642 00:23:19,120 --> 00:23:24,080 have these devices in your possession if 643 00:23:22,000 --> 00:23:25,520 you want to get started with 3d 644 00:23:24,080 --> 00:23:28,080 stereoscopic 645 00:23:25,520 --> 00:23:30,240 photography and so because i of course 646 00:23:28,080 --> 00:23:33,760 want to get you interested in it i'm 647 00:23:30,240 --> 00:23:36,720 going to start talking about gadget free 648 00:23:33,760 --> 00:23:40,000 stereograms so stereograms that you can 649 00:23:36,720 --> 00:23:42,799 create with any regular camera 650 00:23:40,000 --> 00:23:45,120 so i'm about to show you a stereo 651 00:23:42,799 --> 00:23:47,679 photography technique that works with 652 00:23:45,120 --> 00:23:49,679 literally any digital camera at all so 653 00:23:47,679 --> 00:23:52,400 you can use your dslr you can use a 654 00:23:49,679 --> 00:23:55,520 point shoot camera you can use a gopro 655 00:23:52,400 --> 00:23:56,320 you can use your phone anything 656 00:23:55,520 --> 00:23:57,840 now 657 00:23:56,320 --> 00:23:59,120 i'll have to mention that this is a 658 00:23:57,840 --> 00:24:00,320 technique that doesn't work for candid 659 00:23:59,120 --> 00:24:02,480 shots and it doesn't work for action 660 00:24:00,320 --> 00:24:06,559 shots but you can make absolutely 661 00:24:02,480 --> 00:24:09,840 stunning 3d views of buildings and parks 662 00:24:06,559 --> 00:24:11,919 and statues and sculptures and 663 00:24:09,840 --> 00:24:13,600 landscapes and you can even do post 664 00:24:11,919 --> 00:24:15,520 portraits this way so if you have 665 00:24:13,600 --> 00:24:17,360 somebody that can actually sit for a 666 00:24:15,520 --> 00:24:19,760 portrait for you and can hold still for 667 00:24:17,360 --> 00:24:21,360 like 15 to 30 seconds then you can 668 00:24:19,760 --> 00:24:23,760 totally apply this technique to 669 00:24:21,360 --> 00:24:25,919 portraits as well 670 00:24:23,760 --> 00:24:27,840 and i have a small video uh for this 671 00:24:25,919 --> 00:24:29,440 that i'm going to narrate over 672 00:24:27,840 --> 00:24:31,600 so this is me 673 00:24:29,440 --> 00:24:33,679 in my backyard 674 00:24:31,600 --> 00:24:35,200 taking an image of this little garden 675 00:24:33,679 --> 00:24:38,240 ornament that you see and the technique 676 00:24:35,200 --> 00:24:40,000 is really simple i lean on my left foot 677 00:24:38,240 --> 00:24:42,799 so i've got all my weight on my left leg 678 00:24:40,000 --> 00:24:44,799 i snap a picture and then i move over i 679 00:24:42,799 --> 00:24:46,480 move my weight over to my right leg and 680 00:24:44,799 --> 00:24:48,720 snap another picture 681 00:24:46,480 --> 00:24:50,480 that's literally it right 682 00:24:48,720 --> 00:24:52,559 i'm going to give you this on a loop so 683 00:24:50,480 --> 00:24:55,520 you can see it a few times but it's like 684 00:24:52,559 --> 00:24:58,159 really really simple what you want to do 685 00:24:55,520 --> 00:25:00,000 weight on your left leg snap 686 00:24:58,159 --> 00:25:02,400 shift your weight over to your right leg 687 00:25:00,000 --> 00:25:04,400 snap and what that will create 688 00:25:02,400 --> 00:25:06,159 is two images 689 00:25:04,400 --> 00:25:08,159 that have a stereoscopic distance of 690 00:25:06,159 --> 00:25:11,360 about my shoulder width right so they're 691 00:25:08,159 --> 00:25:13,679 pretty solidly hyper stereoscopic even 692 00:25:11,360 --> 00:25:15,679 and if you want to uh take a look at how 693 00:25:13,679 --> 00:25:18,159 that works or how that looks from the 694 00:25:15,679 --> 00:25:20,720 camera this is a view 695 00:25:18,159 --> 00:25:22,559 of the android open camera app exactly 696 00:25:20,720 --> 00:25:23,679 the same thing right so i 697 00:25:22,559 --> 00:25:25,600 frame 698 00:25:23,679 --> 00:25:28,799 the shot with this little ornament in 699 00:25:25,600 --> 00:25:30,000 the center click and then i shift my 700 00:25:28,799 --> 00:25:32,159 weight over 701 00:25:30,000 --> 00:25:34,080 and the whole shot changes a great deal 702 00:25:32,159 --> 00:25:36,400 but the this garden ornament stays in 703 00:25:34,080 --> 00:25:39,200 the center click again 704 00:25:36,400 --> 00:25:41,840 and that's it right 705 00:25:39,200 --> 00:25:43,919 so that's how i create my source images 706 00:25:41,840 --> 00:25:45,600 very simple way to create stereoscopic 707 00:25:43,919 --> 00:25:47,120 images and now how do i turn those into 708 00:25:45,600 --> 00:25:48,799 a stereogram 709 00:25:47,120 --> 00:25:50,320 so we've got two images and now we want 710 00:25:48,799 --> 00:25:51,600 to make a stereogram out of that right 711 00:25:50,320 --> 00:25:53,520 they're not aligned they're not like 712 00:25:51,600 --> 00:25:56,159 whatever and we can do that in a few 713 00:25:53,520 --> 00:25:57,600 very simple steps and of course as 714 00:25:56,159 --> 00:25:59,600 everything as with everything else that 715 00:25:57,600 --> 00:26:01,200 i'm showcasing in this talk i'm using 716 00:25:59,600 --> 00:26:02,240 exclusively free and open source 717 00:26:01,200 --> 00:26:05,360 software 718 00:26:02,240 --> 00:26:08,320 so we're going to do this with the [ __ ] 719 00:26:05,360 --> 00:26:09,120 the canoe image manipulation program 720 00:26:08,320 --> 00:26:10,720 so 721 00:26:09,120 --> 00:26:14,000 what do i do here 722 00:26:10,720 --> 00:26:17,120 well i i've got my two images and i open 723 00:26:14,000 --> 00:26:18,799 them using the open as layers function 724 00:26:17,120 --> 00:26:21,039 in the [ __ ] right so that will simply 725 00:26:18,799 --> 00:26:22,159 create two layers created from these two 726 00:26:21,039 --> 00:26:24,480 images 727 00:26:22,159 --> 00:26:26,240 and now what i'm going to do is i'm 728 00:26:24,480 --> 00:26:29,039 going to rename my layers and i'm going 729 00:26:26,240 --> 00:26:31,520 to rename them left and right 730 00:26:29,039 --> 00:26:32,880 so that they reflect sort of 731 00:26:31,520 --> 00:26:34,960 you know what the view is and then what 732 00:26:32,880 --> 00:26:36,559 i'm going to do is i'm going to take my 733 00:26:34,960 --> 00:26:37,919 right 734 00:26:36,559 --> 00:26:39,840 layer the one that's currently in the 735 00:26:37,919 --> 00:26:42,799 foreground and i'm going to reduce its 736 00:26:39,840 --> 00:26:45,039 opacity to 50 737 00:26:42,799 --> 00:26:48,240 right so that's semi-transparent 738 00:26:45,039 --> 00:26:49,440 and now what i do is i use the [ __ ] move 739 00:26:48,240 --> 00:26:50,640 tool 740 00:26:49,440 --> 00:26:52,640 and 741 00:26:50,640 --> 00:26:53,840 what i want to do is i've got this 742 00:26:52,640 --> 00:26:55,760 little garden ornament that i've 743 00:26:53,840 --> 00:26:57,520 centered as sort of my focal point and 744 00:26:55,760 --> 00:26:59,120 my center of attention and what i want 745 00:26:57,520 --> 00:27:02,960 to do is i want 746 00:26:59,120 --> 00:27:04,480 the image to precisely overlap on that 747 00:27:02,960 --> 00:27:07,120 little ornament so i zoom in a little 748 00:27:04,480 --> 00:27:08,559 bit and i wiggle stuff around until it's 749 00:27:07,120 --> 00:27:10,240 just right 750 00:27:08,559 --> 00:27:11,679 such that i get full overlap on that 751 00:27:10,240 --> 00:27:13,279 little ornament 752 00:27:11,679 --> 00:27:14,880 right just there every everywhere else i 753 00:27:13,279 --> 00:27:16,480 don't care 754 00:27:14,880 --> 00:27:18,799 and then what i do is i do a simple 755 00:27:16,480 --> 00:27:20,799 rectangle select 756 00:27:18,799 --> 00:27:22,799 because now my my layers are only 757 00:27:20,799 --> 00:27:24,080 partially overlapping right and what i 758 00:27:22,799 --> 00:27:25,440 want to do is i want to select the 759 00:27:24,080 --> 00:27:27,600 portion where 760 00:27:25,440 --> 00:27:29,760 they overlap right and i do that with a 761 00:27:27,600 --> 00:27:31,760 simple freehand rectangle select i'm 762 00:27:29,760 --> 00:27:33,760 sure you can write a plugin or a script 763 00:27:31,760 --> 00:27:34,720 or something for that as well but i do a 764 00:27:33,760 --> 00:27:37,919 simple 765 00:27:34,720 --> 00:27:43,840 freehand rectangle select 766 00:27:37,919 --> 00:27:45,440 and once i have that i can use the image 767 00:27:43,840 --> 00:27:47,360 crop to selection option crop to 768 00:27:45,440 --> 00:27:49,679 selection cuts through all the layers 769 00:27:47,360 --> 00:27:51,679 and that means i now have layers that 770 00:27:49,679 --> 00:27:54,159 are exactly identically sized and then 771 00:27:51,679 --> 00:27:55,360 have this little garden ornament in 772 00:27:54,159 --> 00:27:57,760 the center or 773 00:27:55,360 --> 00:27:59,120 that point is is precisely overlapping 774 00:27:57,760 --> 00:28:01,120 and now i have to decide do i want to 775 00:27:59,120 --> 00:28:02,559 make a cross-eyed or a warlike image and 776 00:28:01,120 --> 00:28:05,600 i want to make a cross-side image so 777 00:28:02,559 --> 00:28:08,159 what i do now is i take the right layer 778 00:28:05,600 --> 00:28:10,000 and i move it to the left 779 00:28:08,159 --> 00:28:11,600 right and that creates my cross view 780 00:28:10,000 --> 00:28:13,440 image and then of course you know it's 781 00:28:11,600 --> 00:28:16,080 invisible so i have to resize my canvas 782 00:28:13,440 --> 00:28:17,919 to the layer sizes that's trivial and 783 00:28:16,080 --> 00:28:20,320 then i do one other thing 784 00:28:17,919 --> 00:28:22,640 i leave a little bit of a gap between 785 00:28:20,320 --> 00:28:24,880 and then i create um 786 00:28:22,640 --> 00:28:26,720 a single unique color layer i usually 787 00:28:24,880 --> 00:28:28,720 use white or black and then i put that 788 00:28:26,720 --> 00:28:30,320 into the background because what that 789 00:28:28,720 --> 00:28:32,720 does is it creates this little bar in 790 00:28:30,320 --> 00:28:34,720 the center and when viewing that kind of 791 00:28:32,720 --> 00:28:36,559 tends to nicely frame the image and 792 00:28:34,720 --> 00:28:38,480 guide the eyes right 793 00:28:36,559 --> 00:28:41,039 so that's my stereo my stereogram that 794 00:28:38,480 --> 00:28:45,360 i've created in just a few minutes of 795 00:28:41,039 --> 00:28:47,200 the [ __ ] and this is the result 796 00:28:45,360 --> 00:28:49,120 right so this is a cross-side stereogram 797 00:28:47,200 --> 00:28:51,440 again i'll leave this up for a few 798 00:28:49,120 --> 00:28:53,520 seconds admittedly this one is more 799 00:28:51,440 --> 00:28:56,080 difficult to do than the others because 800 00:28:53,520 --> 00:28:58,480 the background is a little busier 801 00:28:56,080 --> 00:29:01,360 but if you've 802 00:28:58,480 --> 00:29:03,520 managed to do a cross-eyed view of the 803 00:29:01,360 --> 00:29:05,919 image that i gave you earlier chances 804 00:29:03,520 --> 00:29:07,600 are that you're going to do fine with 805 00:29:05,919 --> 00:29:09,679 this one as well 806 00:29:07,600 --> 00:29:11,440 the only thing that you want to perhaps 807 00:29:09,679 --> 00:29:13,840 keep in mind is you want to keep your 808 00:29:11,440 --> 00:29:17,200 attention focused on this little orange 809 00:29:13,840 --> 00:29:20,240 glass bit of of that garden ornament 810 00:29:17,200 --> 00:29:22,320 so you can so you can focus on that 811 00:29:20,240 --> 00:29:24,399 and again i'm going to leave this up for 812 00:29:22,320 --> 00:29:26,640 a few more seconds 813 00:29:24,399 --> 00:29:30,320 and then hopefully what you're going to 814 00:29:26,640 --> 00:29:31,840 see is the depth differences between 815 00:29:30,320 --> 00:29:34,880 this little ornament 816 00:29:31,840 --> 00:29:37,600 and the lilies and the little 817 00:29:34,880 --> 00:29:39,120 maple tree that's growing there and uh 818 00:29:37,600 --> 00:29:42,320 and everything else and the fact that 819 00:29:39,120 --> 00:29:44,480 it's sort of staggered in in depth and 820 00:29:42,320 --> 00:29:46,159 and distance 821 00:29:44,480 --> 00:29:50,240 and that's how we create stereograms in 822 00:29:46,159 --> 00:29:50,240 just a few minutes in the [ __ ] 823 00:29:53,600 --> 00:29:57,120 all right 824 00:29:54,399 --> 00:30:00,559 on to something even more exciting 825 00:29:57,120 --> 00:30:03,679 stereoscopic motion picture aka 3d 826 00:30:00,559 --> 00:30:04,880 movies or motion stereograms so there's 827 00:30:03,679 --> 00:30:06,240 one thing that i think is probably 828 00:30:04,880 --> 00:30:07,760 self-evident right which is that 829 00:30:06,240 --> 00:30:10,159 everything that i talked about for still 830 00:30:07,760 --> 00:30:11,600 photography that relied on using special 831 00:30:10,159 --> 00:30:13,360 lenses or lens attachment or something 832 00:30:11,600 --> 00:30:16,240 like that all that also goes for for 833 00:30:13,360 --> 00:30:17,520 videography right because your dslr or 834 00:30:16,240 --> 00:30:19,600 any other camera including your phone 835 00:30:17,520 --> 00:30:22,480 really can do video just as well as 836 00:30:19,600 --> 00:30:23,919 still so if i if i use this 837 00:30:22,480 --> 00:30:26,799 just you know my regular camera which 838 00:30:23,919 --> 00:30:28,799 can of course do video and i attach this 839 00:30:26,799 --> 00:30:32,159 lens to it then 840 00:30:28,799 --> 00:30:33,120 i get 3d video from that right 841 00:30:32,159 --> 00:30:35,440 but 842 00:30:33,120 --> 00:30:37,600 i'd argue that most people today will be 843 00:30:35,440 --> 00:30:39,120 interested in using a different kind of 844 00:30:37,600 --> 00:30:41,919 camera for 845 00:30:39,120 --> 00:30:44,320 3d video namely a drone camera i don't 846 00:30:41,919 --> 00:30:45,840 know about you i love aerial videography 847 00:30:44,320 --> 00:30:48,399 i think it can be absolutely amazing to 848 00:30:45,840 --> 00:30:51,360 begin with and now imagine shooting 849 00:30:48,399 --> 00:30:52,960 aerial video that's stereoscopic right 850 00:30:51,360 --> 00:30:54,320 now of course what you could do is you 851 00:30:52,960 --> 00:30:56,399 could build your own drone perhaps 852 00:30:54,320 --> 00:30:58,559 something like a fixed wing uav that has 853 00:30:56,399 --> 00:31:00,399 a wingspan of two meters and it has a 854 00:30:58,559 --> 00:31:02,320 gopro embedded in each wing and that 855 00:31:00,399 --> 00:31:03,919 would result in sort of seriously hyper 856 00:31:02,320 --> 00:31:06,000 stereoscopic image and it will give you 857 00:31:03,919 --> 00:31:07,679 the impression or the feel of being 858 00:31:06,000 --> 00:31:10,159 something like a pteranodon science 859 00:31:07,679 --> 00:31:12,640 creature soaring over the earth 860 00:31:10,159 --> 00:31:14,799 but there's a few issues with that right 861 00:31:12,640 --> 00:31:15,600 one we're not all triggered 862 00:31:14,799 --> 00:31:18,080 two 863 00:31:15,600 --> 00:31:20,799 it would come at significant expense and 864 00:31:18,080 --> 00:31:23,279 three you'd need an airstrip for this 865 00:31:20,799 --> 00:31:26,000 whole thing to sort of take off from and 866 00:31:23,279 --> 00:31:27,600 land on right so that's perhaps a bit 867 00:31:26,000 --> 00:31:28,399 problematic 868 00:31:27,600 --> 00:31:29,679 but 869 00:31:28,399 --> 00:31:32,159 there's something very exciting that you 870 00:31:29,679 --> 00:31:34,159 can do you can totally get 3d footage 871 00:31:32,159 --> 00:31:35,760 with a single camera 872 00:31:34,159 --> 00:31:36,720 one that's mounted it could be mounted 873 00:31:35,760 --> 00:31:38,720 on your drum but it could also be 874 00:31:36,720 --> 00:31:40,720 mounted on your car your bicycle 875 00:31:38,720 --> 00:31:43,200 wherever so let me quickly explain the 876 00:31:40,720 --> 00:31:46,000 principle so you already know that any 877 00:31:43,200 --> 00:31:47,519 stereogram consists of a left eye and a 878 00:31:46,000 --> 00:31:49,840 right eye image and of course that also 879 00:31:47,519 --> 00:31:52,320 is true for a motion stereogram but i'm 880 00:31:49,840 --> 00:31:55,679 talking about having only one camera 881 00:31:52,320 --> 00:31:58,480 with only one lens right so imagine 882 00:31:55,679 --> 00:32:00,960 let's take this this gopro here right 883 00:31:58,480 --> 00:32:03,679 and i hold it up to my right eye 884 00:32:00,960 --> 00:32:05,279 right so that's my right eye view 885 00:32:03,679 --> 00:32:07,679 but if i have only one camera where's my 886 00:32:05,279 --> 00:32:11,760 corresponding left eye view 887 00:32:07,679 --> 00:32:13,120 well once i add some sideways motion 888 00:32:11,760 --> 00:32:15,120 right 889 00:32:13,120 --> 00:32:18,000 sideways motion relative to where my 890 00:32:15,120 --> 00:32:20,080 lens is pointed then you quickly realize 891 00:32:18,000 --> 00:32:22,799 that my left eye view is simply where my 892 00:32:20,080 --> 00:32:24,480 right eye view was a moment ago 893 00:32:22,799 --> 00:32:26,480 and we can harness that fact in video 894 00:32:24,480 --> 00:32:29,360 post production to create a 3d video 895 00:32:26,480 --> 00:32:32,640 from a 2d video just as long as it 896 00:32:29,360 --> 00:32:34,399 includes constant lateral motion 897 00:32:32,640 --> 00:32:37,120 so how do we do that 898 00:32:34,399 --> 00:32:39,679 right how do we harness sideways motion 899 00:32:37,120 --> 00:32:41,360 for a 3d effect there's a little bit of 900 00:32:39,679 --> 00:32:44,640 very simple maths that we need to do for 901 00:32:41,360 --> 00:32:47,200 that so suppose that we're shooting uh 902 00:32:44,640 --> 00:32:49,760 video at 50 frames per second right 903 00:32:47,200 --> 00:32:50,880 so that means that um 904 00:32:49,760 --> 00:32:53,200 we're 905 00:32:50,880 --> 00:32:54,399 every frame is 20 milliseconds in 906 00:32:53,200 --> 00:32:56,320 duration 907 00:32:54,399 --> 00:32:59,360 so therefore if we're moving 908 00:32:56,320 --> 00:33:01,200 perpendicular to the direction of view 909 00:32:59,360 --> 00:33:02,799 okay so the camera's pointed this way 910 00:33:01,200 --> 00:33:04,640 we're moving that way 911 00:33:02,799 --> 00:33:06,399 um and we're doing that at even one 912 00:33:04,640 --> 00:33:08,559 meter per second which is roughly the 913 00:33:06,399 --> 00:33:09,760 speed of a leisurely walk and of course 914 00:33:08,559 --> 00:33:12,320 also means that we're moving in one 915 00:33:09,760 --> 00:33:15,039 millimeter per millisecond right so that 916 00:33:12,320 --> 00:33:17,600 means that one frame covers about 20 917 00:33:15,039 --> 00:33:20,399 millimeters in sideways motion 918 00:33:17,600 --> 00:33:22,559 so therefore if we duplicate our stream 919 00:33:20,399 --> 00:33:24,799 and put the two stream copies side by 920 00:33:22,559 --> 00:33:25,840 side and then offset one of them by four 921 00:33:24,799 --> 00:33:27,840 frames 922 00:33:25,840 --> 00:33:29,600 or 80 milliseconds 923 00:33:27,840 --> 00:33:31,120 then what we've effectively achieved is 924 00:33:29,600 --> 00:33:32,399 a stereoscopic distance of 80 925 00:33:31,120 --> 00:33:33,120 millimeters 926 00:33:32,399 --> 00:33:34,960 and 927 00:33:33,120 --> 00:33:36,559 our pupils are 70 millimeters apart so 928 00:33:34,960 --> 00:33:39,200 that's nicely 929 00:33:36,559 --> 00:33:42,320 iso stereoscopic 930 00:33:39,200 --> 00:33:43,360 if we go a step further and uh 931 00:33:42,320 --> 00:33:44,720 we 932 00:33:43,360 --> 00:33:46,399 uh 933 00:33:44,720 --> 00:33:48,159 make with we're thinking about an object 934 00:33:46,399 --> 00:33:51,120 that goes a little faster so say for 935 00:33:48,159 --> 00:33:53,519 example a drone right or a bicycle or 936 00:33:51,120 --> 00:33:55,519 something like that a car is easy 937 00:33:53,519 --> 00:33:57,679 but any any of those can achieve 10 938 00:33:55,519 --> 00:34:00,640 meters per second right 939 00:33:57,679 --> 00:34:03,039 or 36 kilometers an hour um 940 00:34:00,640 --> 00:34:04,960 so when you do that then even a single 941 00:34:03,039 --> 00:34:07,200 frame offset gives you a stereoscopic 942 00:34:04,960 --> 00:34:08,879 distance of 200 millimeters right which 943 00:34:07,200 --> 00:34:11,040 already makes the video solidly hyper 944 00:34:08,879 --> 00:34:12,560 stereoscopic and if you use for example 945 00:34:11,040 --> 00:34:14,560 a five frame offset it gives you a nice 946 00:34:12,560 --> 00:34:17,040 giant's eye view with like a one meter 947 00:34:14,560 --> 00:34:18,639 stereo distance and this becomes 948 00:34:17,040 --> 00:34:22,320 especially interesting when you're 949 00:34:18,639 --> 00:34:24,240 either doing a linear drone flight along 950 00:34:22,320 --> 00:34:26,159 a roughly linear feature so say for 951 00:34:24,240 --> 00:34:28,480 example you're tracking a coastline 952 00:34:26,159 --> 00:34:31,119 or you're doing orbital flight around an 953 00:34:28,480 --> 00:34:32,800 object right so ideally one with where 954 00:34:31,119 --> 00:34:36,000 you're orbiting above 955 00:34:32,800 --> 00:34:37,760 and your camera is is tilted slightly 956 00:34:36,000 --> 00:34:40,560 downward 957 00:34:37,760 --> 00:34:42,800 and i've got an example of the former of 958 00:34:40,560 --> 00:34:45,599 these two so what you see here 959 00:34:42,800 --> 00:34:48,399 is a drone flight sequence that's shot 960 00:34:45,599 --> 00:34:50,159 at 30 frames per second with the camera 961 00:34:48,399 --> 00:34:52,000 pointing forwards and the drone flying 962 00:34:50,159 --> 00:34:54,960 sideways 963 00:34:52,000 --> 00:34:58,160 um and it's going to the right and it's 964 00:34:54,960 --> 00:35:01,839 going at approximately 40 kilometers an 965 00:34:58,160 --> 00:35:04,079 hour or 11.1 meters per second right or 966 00:35:01,839 --> 00:35:05,359 put differently uh this is buffering a 967 00:35:04,079 --> 00:35:06,480 little bit but 968 00:35:05,359 --> 00:35:08,880 you can 969 00:35:06,480 --> 00:35:10,800 follow the um you can follow the video 970 00:35:08,880 --> 00:35:12,720 stream in the in the slide link that we 971 00:35:10,800 --> 00:35:15,040 uh shared at the top of the talk so 972 00:35:12,720 --> 00:35:18,560 anyhow um 973 00:35:15,040 --> 00:35:19,920 the we're going uh sideways at 11.1 974 00:35:18,560 --> 00:35:21,599 meters per second 975 00:35:19,920 --> 00:35:22,960 camera is pointing forwards put 976 00:35:21,599 --> 00:35:24,480 differently drones flying forwards at 977 00:35:22,960 --> 00:35:25,920 11.1 meters per second camera is 978 00:35:24,480 --> 00:35:28,960 pointing 90 degrees to the left it's 979 00:35:25,920 --> 00:35:30,960 exactly the same thing so and i it bears 980 00:35:28,960 --> 00:35:32,960 mentioning that um the camera doesn't 981 00:35:30,960 --> 00:35:35,280 need to be pointed at a 90 degree angle 982 00:35:32,960 --> 00:35:37,040 versus the heading of flight uh we could 983 00:35:35,280 --> 00:35:38,800 also for example be pointing the camera 984 00:35:37,040 --> 00:35:40,720 directly short and then fly at the beach 985 00:35:38,800 --> 00:35:43,359 at a 45 degree angle but what matters is 986 00:35:40,720 --> 00:35:45,359 that we have some lateral motion and 987 00:35:43,359 --> 00:35:47,680 that we're able to quantify it which 988 00:35:45,359 --> 00:35:50,800 which saves us some guesswork 989 00:35:47,680 --> 00:35:52,720 so every time every 90 milliseconds 990 00:35:50,800 --> 00:35:54,320 the camera is laterally displaced one 991 00:35:52,720 --> 00:35:56,320 meter and that's a nice hyper 992 00:35:54,320 --> 00:35:59,200 stereoscopic distance that we can work 993 00:35:56,320 --> 00:36:00,800 with in this panoramic shot so how do we 994 00:35:59,200 --> 00:36:03,280 turn this into 995 00:36:00,800 --> 00:36:04,720 a 3d movie 996 00:36:03,280 --> 00:36:06,240 again 997 00:36:04,720 --> 00:36:08,400 wonderful open source software to the 998 00:36:06,240 --> 00:36:10,000 rescue this is my favorite video editor 999 00:36:08,400 --> 00:36:12,079 happens to be shortcut 1000 00:36:10,000 --> 00:36:14,160 and what you see here is i've got the 1001 00:36:12,079 --> 00:36:16,400 same video opened twice in shortcut in 1002 00:36:14,160 --> 00:36:18,160 my playlist that's just a ux quirk in 1003 00:36:16,400 --> 00:36:20,400 shortcut um 1004 00:36:18,160 --> 00:36:21,680 i need to do it this way because there's 1005 00:36:20,400 --> 00:36:23,839 certain things that i can't do with one 1006 00:36:21,680 --> 00:36:26,560 of them never mind it's exactly the same 1007 00:36:23,839 --> 00:36:28,720 the same sequence so what i'm doing is 1008 00:36:26,560 --> 00:36:30,720 i'm adding a video track 1009 00:36:28,720 --> 00:36:32,720 for the left eye image 1010 00:36:30,720 --> 00:36:34,560 and note we're again going to be making 1011 00:36:32,720 --> 00:36:36,160 a cross view video so this image will 1012 00:36:34,560 --> 00:36:38,160 actually end up on the right so i'm 1013 00:36:36,160 --> 00:36:39,599 pulling this clip down into into the 1014 00:36:38,160 --> 00:36:43,280 track here 1015 00:36:39,599 --> 00:36:45,760 and then what i'll do is i'll apply two 1016 00:36:43,280 --> 00:36:48,320 filters very simple filters so the first 1017 00:36:45,760 --> 00:36:51,040 one is a crop filter 1018 00:36:48,320 --> 00:36:53,440 and what i want to do is i want to sort 1019 00:36:51,040 --> 00:36:55,280 of extract out of this 1020 00:36:53,440 --> 00:36:56,960 widescreen view i want to extract sort 1021 00:36:55,280 --> 00:36:58,480 of just the middle bit 1022 00:36:56,960 --> 00:37:00,480 and so therefore 1023 00:36:58,480 --> 00:37:01,760 what i'm going to do is i'm going to 1024 00:37:00,480 --> 00:37:06,079 take a crop 1025 00:37:01,760 --> 00:37:10,079 of half the width of the whole frame 1026 00:37:06,079 --> 00:37:14,720 so it has an original width of 2704 so 1027 00:37:10,079 --> 00:37:17,760 i'm going to drop it to our 1352 1028 00:37:14,720 --> 00:37:21,560 in width so 1352 pixels and of course 1029 00:37:17,760 --> 00:37:21,560 the height stays unchanged 1030 00:37:22,400 --> 00:37:25,440 and then what i'll also do is i'll 1031 00:37:24,400 --> 00:37:26,560 offset my crop 1032 00:37:25,440 --> 00:37:29,839 [Music] 1033 00:37:26,560 --> 00:37:32,560 by one quarter of the image width so 1034 00:37:29,839 --> 00:37:34,480 that's 776 pixels that you see here so 1035 00:37:32,560 --> 00:37:36,560 what we're chopping out we're taking out 1036 00:37:34,480 --> 00:37:38,960 sort of the left and the right side and 1037 00:37:36,560 --> 00:37:40,560 we're just leaving the middle 1038 00:37:38,960 --> 00:37:42,640 okay and now what i'm going to do is i'm 1039 00:37:40,560 --> 00:37:44,160 going to use a position filter to move 1040 00:37:42,640 --> 00:37:46,160 this cropped 1041 00:37:44,160 --> 00:37:48,160 frame 1042 00:37:46,160 --> 00:37:50,320 all the way over to the 1043 00:37:48,160 --> 00:37:52,320 right all right it's the left eye image 1044 00:37:50,320 --> 00:37:55,520 it moves over to the right because we're 1045 00:37:52,320 --> 00:37:57,839 building a cross view video 1046 00:37:55,520 --> 00:37:59,440 all right so 1047 00:37:57,839 --> 00:38:01,200 that's 1048 00:37:59,440 --> 00:38:04,320 the left eye image 1049 00:38:01,200 --> 00:38:06,800 now add a second track pull the exact 1050 00:38:04,320 --> 00:38:09,520 same video into that track 1051 00:38:06,800 --> 00:38:14,320 and then we're also going to be doing a 1052 00:38:09,520 --> 00:38:14,320 little bit of play with filters 1053 00:38:16,079 --> 00:38:20,320 so there we go we're pulling that down 1054 00:38:18,400 --> 00:38:22,880 uh into our track at this point it's 1055 00:38:20,320 --> 00:38:25,280 it's identically aligned and now uh 1056 00:38:22,880 --> 00:38:28,160 we're applying the same filters 1057 00:38:25,280 --> 00:38:29,520 so first a crop filter the crop filter 1058 00:38:28,160 --> 00:38:31,520 is going to use exactly the same 1059 00:38:29,520 --> 00:38:32,960 parameters as 1060 00:38:31,520 --> 00:38:36,000 with the 1061 00:38:32,960 --> 00:38:40,320 left eye image so we're going to 1062 00:38:36,000 --> 00:38:42,320 reduce its size its width to 1352 1063 00:38:40,320 --> 00:38:44,320 and we're going to 1064 00:38:42,320 --> 00:38:47,200 use the middle portion so we're going to 1065 00:38:44,320 --> 00:38:49,280 offset this by 776 but now i do 1066 00:38:47,200 --> 00:38:50,960 something i do the reverse of what i did 1067 00:38:49,280 --> 00:38:53,960 earlier with the position filter with 1068 00:38:50,960 --> 00:38:57,280 the position filter i now use a negative 1069 00:38:53,960 --> 00:38:59,440 776 pixel offset so that this thing 1070 00:38:57,280 --> 00:39:00,480 moves to the left gets jammed over to 1071 00:38:59,440 --> 00:39:02,800 the left 1072 00:39:00,480 --> 00:39:04,240 uh the left edge of the frame and then 1073 00:39:02,800 --> 00:39:06,400 there's one tiny little thing that i 1074 00:39:04,240 --> 00:39:08,800 need to do i have this bar here that 1075 00:39:06,400 --> 00:39:11,040 overlaps and of course i don't want that 1076 00:39:08,800 --> 00:39:12,240 so uh what i'll do is i'll change the 1077 00:39:11,040 --> 00:39:15,040 blend mode 1078 00:39:12,240 --> 00:39:17,359 to add and there we go so now we've got 1079 00:39:15,040 --> 00:39:19,760 the two images side by side 1080 00:39:17,359 --> 00:39:23,520 and now comes the magic right so now 1081 00:39:19,760 --> 00:39:25,040 what we do is we take one of our one of 1082 00:39:23,520 --> 00:39:26,880 our tracks 1083 00:39:25,040 --> 00:39:31,040 and we offset it 1084 00:39:26,880 --> 00:39:32,960 by 90 milliseconds versus the other 1085 00:39:31,040 --> 00:39:34,880 all right and so what i'll do here is 1086 00:39:32,960 --> 00:39:36,800 this takes me a little bit of fiddling 1087 00:39:34,880 --> 00:39:38,960 because at the time when i uh when i 1088 00:39:36,800 --> 00:39:41,359 screen capped this i didn't know the 1089 00:39:38,960 --> 00:39:43,440 shortcut yet to make this happen in 1090 00:39:41,359 --> 00:39:45,119 shortcut so forgive me for that so i'm 1091 00:39:43,440 --> 00:39:47,079 just positioning the playhead i'm 1092 00:39:45,119 --> 00:39:50,160 roughly eyeballing this to 1093 00:39:47,079 --> 00:39:51,359 .09 seconds 1094 00:39:50,160 --> 00:39:53,280 and then 1095 00:39:51,359 --> 00:39:55,119 once i found that which like i said took 1096 00:39:53,280 --> 00:39:57,599 me a few tries 1097 00:39:55,119 --> 00:40:02,640 i can 1098 00:39:57,599 --> 00:40:02,640 move and then split my tracks 1099 00:40:04,400 --> 00:40:07,400 so 1100 00:40:11,119 --> 00:40:14,960 so there we go now we're moving that one 1101 00:40:12,880 --> 00:40:16,880 track by that offset 1102 00:40:14,960 --> 00:40:18,160 and now everything else that remains is 1103 00:40:16,880 --> 00:40:20,319 just trimming 1104 00:40:18,160 --> 00:40:22,079 right we're trimming a little bit at the 1105 00:40:20,319 --> 00:40:24,240 at the start and we're trimming a little 1106 00:40:22,079 --> 00:40:25,760 bit at the back and then we're moving 1107 00:40:24,240 --> 00:40:27,680 everything back to 1108 00:40:25,760 --> 00:40:31,040 this to to the beginning of the track to 1109 00:40:27,680 --> 00:40:31,040 the start of the track to the zero mark 1110 00:40:31,520 --> 00:40:35,520 okay so there we go 1111 00:40:33,680 --> 00:40:39,839 i just find another spot here with the 1112 00:40:35,520 --> 00:40:39,839 playhead again i completely eyeball this 1113 00:40:40,240 --> 00:40:45,160 and i split 1114 00:40:41,839 --> 00:40:45,160 and i trim 1115 00:40:54,160 --> 00:41:01,720 and now that that's done i just move 1116 00:40:56,640 --> 00:41:01,720 everything to the start of the track 1117 00:41:10,640 --> 00:41:14,480 and that's it 1118 00:41:12,160 --> 00:41:18,480 and now we can render this thing 1119 00:41:14,480 --> 00:41:18,480 and we end up with 1120 00:41:19,760 --> 00:41:22,800 a 3d video 1121 00:41:21,680 --> 00:41:25,040 all right 1122 00:41:22,800 --> 00:41:27,359 so again this is exactly the same 1123 00:41:25,040 --> 00:41:29,200 principle you cross your eyes 1124 00:41:27,359 --> 00:41:31,839 you let them wander out a little bit and 1125 00:41:29,200 --> 00:41:33,200 you wait for them to click into place 1126 00:41:31,839 --> 00:41:34,800 right again if you're watching the 1127 00:41:33,200 --> 00:41:37,359 recording or maybe you're watching the 1128 00:41:34,800 --> 00:41:40,000 original on on youtube you probably want 1129 00:41:37,359 --> 00:41:42,800 to pause the stream at some point and 1130 00:41:40,000 --> 00:41:44,720 just find your find your spot at the 1131 00:41:42,800 --> 00:41:46,480 very beginning of that loop there's a 1132 00:41:44,720 --> 00:41:48,480 house in the middle that kind of lends 1133 00:41:46,480 --> 00:41:50,480 itself to being a nice little focal 1134 00:41:48,480 --> 00:41:52,400 point 1135 00:41:50,480 --> 00:41:54,560 and i'll give you this on a loop here a 1136 00:41:52,400 --> 00:41:57,520 few times as well 1137 00:41:54,560 --> 00:42:00,079 i realize it's probably a little bit 1138 00:41:57,520 --> 00:42:02,800 jerky right now like i said you've got 1139 00:42:00,079 --> 00:42:05,599 all the links available and you can look 1140 00:42:02,800 --> 00:42:08,480 at the original footage but in principle 1141 00:42:05,599 --> 00:42:10,160 this works exactly the same way as a 1142 00:42:08,480 --> 00:42:12,800 stereo photograph 1143 00:42:10,160 --> 00:42:14,560 and once you get the hang of it it's 1144 00:42:12,800 --> 00:42:16,560 really nice because in this case you 1145 00:42:14,560 --> 00:42:18,240 sort of see how 1146 00:42:16,560 --> 00:42:20,160 there's like different layers of depth 1147 00:42:18,240 --> 00:42:22,319 in the jungle that are staggered uh 1148 00:42:20,160 --> 00:42:23,280 there's houses kind of like in between 1149 00:42:22,319 --> 00:42:24,960 there 1150 00:42:23,280 --> 00:42:26,720 and and they are all at like different 1151 00:42:24,960 --> 00:42:28,160 depths there's two ridge lines in the 1152 00:42:26,720 --> 00:42:30,400 back actually three ridge lines in the 1153 00:42:28,160 --> 00:42:33,280 background and you kind of nicely see 1154 00:42:30,400 --> 00:42:35,359 the relative depth of those and and so 1155 00:42:33,280 --> 00:42:37,280 on and it's it's it's pretty neat uh 1156 00:42:35,359 --> 00:42:39,440 when it turns out that way and that's 1157 00:42:37,280 --> 00:42:41,440 how we get 3d footage of flying along a 1158 00:42:39,440 --> 00:42:45,520 brazilian beach with a view of the 1159 00:42:41,440 --> 00:42:46,319 jungle with just a single camera 1160 00:42:45,520 --> 00:42:48,000 now 1161 00:42:46,319 --> 00:42:50,720 uh with that 1162 00:42:48,000 --> 00:42:53,599 i hope i've peaked your curiosity for 1163 00:42:50,720 --> 00:42:54,640 stereoscopic photography 1164 00:42:53,599 --> 00:42:57,040 a little bit 1165 00:42:54,640 --> 00:42:59,359 and i'll have a few more stereo images 1166 00:42:57,040 --> 00:43:01,440 here to close out the talk for those of 1167 00:42:59,359 --> 00:43:02,720 you who have already mastered the art of 1168 00:43:01,440 --> 00:43:04,880 cross site previewing these will 1169 00:43:02,720 --> 00:43:07,200 probably be a breeze 1170 00:43:04,880 --> 00:43:08,079 so this here is a shot 1171 00:43:07,200 --> 00:43:10,400 of 1172 00:43:08,079 --> 00:43:13,359 reconstructed roman baths in what used 1173 00:43:10,400 --> 00:43:15,839 to be the capital of uh the roman 1174 00:43:13,359 --> 00:43:18,240 province of pannonia superior in 1175 00:43:15,839 --> 00:43:20,800 kanuntum uh today this is about a 45 1176 00:43:18,240 --> 00:43:23,040 minute drive away from 1177 00:43:20,800 --> 00:43:24,400 vienna 45 minute drive east of vienna 1178 00:43:23,040 --> 00:43:26,640 approximately 1179 00:43:24,400 --> 00:43:28,480 and that gives you uh when when that 1180 00:43:26,640 --> 00:43:30,319 clicks into place that also gives you 1181 00:43:28,480 --> 00:43:32,079 sort of a nice view of the relative 1182 00:43:30,319 --> 00:43:34,240 depth of the buildings there's these 1183 00:43:32,079 --> 00:43:36,880 neatly trimmed bushes in front uh 1184 00:43:34,240 --> 00:43:39,040 there's some trees in the background 1185 00:43:36,880 --> 00:43:40,480 uh and so on 1186 00:43:39,040 --> 00:43:44,560 uh here's 1187 00:43:40,480 --> 00:43:44,560 another image coming up now 1188 00:43:44,960 --> 00:43:48,079 that apparently takes a little bit to 1189 00:43:46,800 --> 00:43:50,480 load 1190 00:43:48,079 --> 00:43:53,480 for some reason and i'm not really sure 1191 00:43:50,480 --> 00:43:53,480 why 1192 00:43:54,240 --> 00:44:00,000 that's great florian i'm just imagining 1193 00:43:57,200 --> 00:44:02,640 this talk in real life uh at the 1194 00:44:00,000 --> 00:44:04,400 conference and a room full of lca is 1195 00:44:02,640 --> 00:44:05,839 stumbling around during the broom 1196 00:44:04,400 --> 00:44:08,960 changeover 1197 00:44:05,839 --> 00:44:11,599 trying to uncross eye themselves 1198 00:44:08,960 --> 00:44:14,640 um we do have one question from the chat 1199 00:44:11,599 --> 00:44:16,960 if you've got got a moment to take it 1200 00:44:14,640 --> 00:44:18,960 um have you tried using any of the 1201 00:44:16,960 --> 00:44:23,200 various vr headsets that are in the 1202 00:44:18,960 --> 00:44:24,960 market as a stereogram viewer 1203 00:44:23,200 --> 00:44:26,640 i have not 1204 00:44:24,960 --> 00:44:28,240 but in principle 1205 00:44:26,640 --> 00:44:29,760 and i have another version of this talk 1206 00:44:28,240 --> 00:44:31,119 in which i mentioned this so basically a 1207 00:44:29,760 --> 00:44:33,040 vr goggle 1208 00:44:31,119 --> 00:44:35,599 works very much the same way as a 1209 00:44:33,040 --> 00:44:38,000 stereoscope like this except that rather 1210 00:44:35,599 --> 00:44:40,640 than putting a photograph an image in 1211 00:44:38,000 --> 00:44:42,000 here um you've got two screens right so 1212 00:44:40,640 --> 00:44:44,000 in principle it's it's pretty much the 1213 00:44:42,000 --> 00:44:46,560 same thing no i have not used it like i 1214 00:44:44,000 --> 00:44:48,640 said like for me this is uh i mean yes i 1215 00:44:46,560 --> 00:44:52,400 use all these digital tools and whatnot 1216 00:44:48,640 --> 00:44:54,079 but for me viewing this uh is sort of a 1217 00:44:52,400 --> 00:44:56,480 low-tech hobby i want to i want to put 1218 00:44:54,079 --> 00:44:59,040 this stuff sort of on my wall and and be 1219 00:44:56,480 --> 00:45:01,119 able to to look at that um i know we're 1220 00:44:59,040 --> 00:45:03,599 almost out of time i do want to mention 1221 00:45:01,119 --> 00:45:06,240 uh just a couple of more things because 1222 00:45:03,599 --> 00:45:08,160 they're important um i my twitter handle 1223 00:45:06,240 --> 00:45:10,720 was already sort of all over this talk 1224 00:45:08,160 --> 00:45:12,720 um if you do engage in this sort of 1225 00:45:10,720 --> 00:45:15,119 thing please tag me i'd love to see your 1226 00:45:12,720 --> 00:45:17,359 stereo images and uh there's another 1227 00:45:15,119 --> 00:45:20,800 thing that i do want to say which is a 1228 00:45:17,359 --> 00:45:23,440 special thanks to my former colleague 1229 00:45:20,800 --> 00:45:24,480 adolfo branches who took the drone 1230 00:45:23,440 --> 00:45:26,560 footage 1231 00:45:24,480 --> 00:45:29,200 from the brazilian beach and gave me 1232 00:45:26,560 --> 00:45:30,079 permission to use it and i also have a 1233 00:45:29,200 --> 00:45:32,720 few 1234 00:45:30,079 --> 00:45:35,200 creative commons image credits to share 1235 00:45:32,720 --> 00:45:37,599 at the end of the talk do we have any 1236 00:45:35,200 --> 00:45:40,000 more questions 1237 00:45:37,599 --> 00:45:42,240 uh yep we have one more how does this 1238 00:45:40,000 --> 00:45:43,760 relate to magikai books from back in the 1239 00:45:42,240 --> 00:45:46,960 day 1240 00:45:43,760 --> 00:45:48,480 magic ibooks are called auto stereograms 1241 00:45:46,960 --> 00:45:50,079 so 1242 00:45:48,480 --> 00:45:51,760 that's um 1243 00:45:50,079 --> 00:45:54,640 yeah i mean 1244 00:45:51,760 --> 00:45:57,359 that's also it's it simply creates the 1245 00:45:54,640 --> 00:46:00,000 illusion of depth in a different way 1246 00:45:57,359 --> 00:46:01,760 namely by using these actually they're 1247 00:46:00,000 --> 00:46:03,760 probably called random dot stereograms 1248 00:46:01,760 --> 00:46:05,359 so anything that you can free view is 1249 00:46:03,760 --> 00:46:07,599 essentially an autostereogram pretty 1250 00:46:05,359 --> 00:46:10,560 much um and those are called random dot 1251 00:46:07,599 --> 00:46:11,680 stereograms so yes it's pretty much 1252 00:46:10,560 --> 00:46:14,240 similar 1253 00:46:11,680 --> 00:46:16,480 it just yeah it just doesn't come off 1254 00:46:14,240 --> 00:46:18,880 sort of the living object right but it's 1255 00:46:16,480 --> 00:46:21,520 but it's generated there's also people 1256 00:46:18,880 --> 00:46:24,480 that do things like taking 1257 00:46:21,520 --> 00:46:26,000 uh letting [ __ ] build depth maps from 1258 00:46:24,480 --> 00:46:27,440 two different 1259 00:46:26,000 --> 00:46:29,440 uh views 1260 00:46:27,440 --> 00:46:31,520 left eye and right eye views of an image 1261 00:46:29,440 --> 00:46:33,040 and then creating random dot stereograms 1262 00:46:31,520 --> 00:46:34,960 from that but that is something that i 1263 00:46:33,040 --> 00:46:37,119 just know exists i haven't dabbled in it 1264 00:46:34,960 --> 00:46:39,599 i don't know anything about this uh but 1265 00:46:37,119 --> 00:46:40,880 yeah it's it's something uh 1266 00:46:39,599 --> 00:46:42,640 well it was brilliant thank you very 1267 00:46:40,880 --> 00:46:44,800 much um 1268 00:46:42,640 --> 00:46:46,160 thank you actual feedback was really 1269 00:46:44,800 --> 00:46:48,640 good from the chat really good 1270 00:46:46,160 --> 00:46:50,800 engagement everyone was trying out the 1271 00:46:48,640 --> 00:46:53,599 the cross side and different methods it 1272 00:46:50,800 --> 00:46:55,200 was great okay thank you and now we'll 1273 00:46:53,599 --> 00:46:56,800 be back in 10 minutes after the room 1274 00:46:55,200 --> 00:46:58,640 changeover 1275 00:46:56,800 --> 00:47:01,359 so thank you once again florian and 1276 00:46:58,640 --> 00:47:02,960 we'll see you hopefully at the next lca 1277 00:47:01,359 --> 00:47:04,480 yes exactly stay safe and healthy 1278 00:47:02,960 --> 00:47:07,880 everybody and i hope to see you next 1279 00:47:04,480 --> 00:47:07,880 year cheers