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Civil War in 3D: Stereographs from the New-York Historical Society (2015)

58 points by LorenDB 1y ago

deleted 1y ago
[deleted]
ramesh31 1y ago
You can see the effect in these images directly without a device, by simply crossing your eyes and focusing on the third central image that appears, similar to those 3D optical illusion books: https://youtu.be/zBa-bCxsZDk https://youtu.be/zBa-bCxsZDk
- JKCalhoun 1y ago
  The cross-eyed method requires the images be swapped left-for-right.
  - kazinator 1y ago
    Not sure why you are downvoted; that is correct.
- kazinator 1y ago
  This gallery presents the original stereograms in their stare-into-distance configuration (left image goes with left eye, right with right), not cross-eyes configuration (left image goes with right eye and vice versa).
JeremyHerrman 1y ago
Is it just me or are some of these examples not actually stereo image pairs? I'm just crossing my eyes to see the "negative" depth image but some like "McLean’s House" and "Lincoln visits General McClellan at Antietam" don't appear to have any depth changes between them.
- JKCalhoun 1y ago
  You need to swap left and right images to use the cross-eyed method on these. You can try downloading as an image, use an app like Preview to Flip Horizontal (that will work). Otherwise you're seeing a kind of inverse stereo image. (EDIT: Having said that, I tried a few of the images and the stereo effect is subtle. The soldier on the horse — I was not even able to get that to "snap" for me. I am not great with cross-eyed stereo though.)
  - JeremyHerrman 1y ago
    yes understood that cross-eyed method inverts the depth. My point was that some of the image pairs are from the exact same perspective - so there is no stereo depth no matter if you're using cow-eyed or cross-eyed.
    - JKCalhoun 1y ago
      Yeah, if there is depth, it was pretty subtle on the few I got to work.
- kazinator 1y ago
  These images were prepared for insertion into a stereogram in which the left eye looks at the left image and right eye looks at the right image, through a magnifying lens. When viewing with the naked eye, you must stare past the images into the distance to get them to converge that way.
  - JeremyHerrman 1y ago
    Thanks, I understand how stereograms work and have quite a few of these IRL. I use cross-eyed method to quickly view them (albeit inverted depth) when shown on screen. I've tried to show my point in these videos which show basically no difference between the two images when overlapped and crossfaded between the two. https://imgur.com/a/RMy3QA3 https://imgur.com/a/RMy3QA3
    - 1y ago
saddat 1y ago
Create two pictures from it and use https://huggingface.co/spaces/cavargas10/TRELLIS-Multiple3D https://huggingface.co/spaces/cavargas10/TRELLIS-Multiple3D
breck 1y ago
On the topic of stereographs, this 1859 Oliver Wendell Holmes essay in the Atlantic is one of my favorite all time essays: https://www.nhag.org/uploads/2/4/9/1/24914531/holmes_-_stereograph.pdf https://www.nhag.org/uploads/2/4/9/1/24914531/holmes_-_stere...
kazinator 1y ago
For casual viewing with the unaided eye, you want to present stereograms in cross-your-eyes order not stare-into-distance order. Most people are not able to cause their eyes to diverge, so the scale of images in a stare-into-distance stereogram is limited by the interocular distance. In cross-eye configuration, larger images can be used. (Of course, the use of magnification in stereoscopes relieves the issue, as well as making it easier for the eyes to focus, since the magnified virtual images appear farther away. Viewing stare-into-distance stereograms requires the eyes to believe they are looking far away due to the parallel gaze, while simultaneously focusing near on the images; magnification brings the images farther out.)
- LorenDB 1y ago
  I personally find the crosseyed type to be nearly impossible, while the parallel type are pretty easy for me. So I think it really depends on the person. Additionally, most stereograms I've seen (e.g. coffee-table books) have been parallel type.
  - kazinator 1y ago
    The parallel types are also very easy for me, but they are always small. If the spacing between them is wider than my inter-ocular distance, I find them impossible to converge. I made stereograms in the past and wanted to see larger images with the naked eye, so I had no choice but swap the images and cross the eyes.
- 6yyyyyy 1y ago
  I flipped them all, enjoy: https://imgur.com/a/OOiQ5AK https://imgur.com/a/OOiQ5AK (FYI: -vf stereo3d=in=sbsl:out=sbsr in ffmpeg.)
  - entropicdrifter 1y ago
    Woo! The true solution!
- pimlottc 1y ago
ge96 1y ago
For an example that works see this squirrel sorry reddit link https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2Fuphxv0t6wsw51.jpg%3Fwidth%3D640%26crop%3Dsmart%26auto%3Dwebp%26s%3D8a25f471fd9ee6a3b40016f5b6e2cf37fd2f5185 https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.... crazy but I feel sick now ha, I had a VR headset before and I'd get super sick trying to play FO4, VRChat wasn't bad
bredren 1y ago
Would be cool to get these converted into spatial photos for Vision Pro.
- mdswanson 1y ago
  Not too many steps away from this: https://blog.mikeswanson.com/spatial/ https://blog.mikeswanson.com/spatial/

58 points by LorenDB 1y ago

deleted 1y ago

[deleted]

You can see the effect in these images directly without a device, by simply crossing your eyes and focusing on the third central image that appears, similar to those 3D optical illusion books: https://youtu.be/zBa-bCxsZDk https://youtu.be/zBa-bCxsZDk

JKCalhoun 1y ago
The cross-eyed method requires the images be swapped left-for-right.
- kazinator 1y ago
  Not sure why you are downvoted; that is correct.
kazinator 1y ago
This gallery presents the original stereograms in their stare-into-distance configuration (left image goes with left eye, right with right), not cross-eyes configuration (left image goes with right eye and vice versa).

JeremyHerrman 1y ago

Is it just me or are some of these examples not actually stereo image pairs? I'm just crossing my eyes to see the "negative" depth image but some like "McLean’s House" and "Lincoln visits General McClellan at Antietam" don't appear to have any depth changes between them.

JKCalhoun 1y ago
You need to swap left and right images to use the cross-eyed method on these. You can try downloading as an image, use an app like Preview to Flip Horizontal (that will work). Otherwise you're seeing a kind of inverse stereo image. (EDIT: Having said that, I tried a few of the images and the stereo effect is subtle. The soldier on the horse — I was not even able to get that to "snap" for me. I am not great with cross-eyed stereo though.)
- JeremyHerrman 1y ago
  yes understood that cross-eyed method inverts the depth. My point was that some of the image pairs are from the exact same perspective - so there is no stereo depth no matter if you're using cow-eyed or cross-eyed.
  - JKCalhoun 1y ago
    Yeah, if there is depth, it was pretty subtle on the few I got to work.
kazinator 1y ago
These images were prepared for insertion into a stereogram in which the left eye looks at the left image and right eye looks at the right image, through a magnifying lens. When viewing with the naked eye, you must stare past the images into the distance to get them to converge that way.
- JeremyHerrman 1y ago
  Thanks, I understand how stereograms work and have quite a few of these IRL. I use cross-eyed method to quickly view them (albeit inverted depth) when shown on screen. I've tried to show my point in these videos which show basically no difference between the two images when overlapped and crossfaded between the two. https://imgur.com/a/RMy3QA3 https://imgur.com/a/RMy3QA3
  - 1y ago

saddat 1y ago

Create two pictures from it and use https://huggingface.co/spaces/cavargas10/TRELLIS-Multiple3D https://huggingface.co/spaces/cavargas10/TRELLIS-Multiple3D

breck 1y ago

On the topic of stereographs, this 1859 Oliver Wendell Holmes essay in the Atlantic is one of my favorite all time essays: https://www.nhag.org/uploads/2/4/9/1/24914531/holmes_-_stereograph.pdf https://www.nhag.org/uploads/2/4/9/1/24914531/holmes_-_stere...

kazinator 1y ago

For casual viewing with the unaided eye, you want to present stereograms in cross-your-eyes order not stare-into-distance order. Most people are not able to cause their eyes to diverge, so the scale of images in a stare-into-distance stereogram is limited by the interocular distance. In cross-eye configuration, larger images can be used. (Of course, the use of magnification in stereoscopes relieves the issue, as well as making it easier for the eyes to focus, since the magnified virtual images appear farther away. Viewing stare-into-distance stereograms requires the eyes to believe they are looking far away due to the parallel gaze, while simultaneously focusing near on the images; magnification brings the images farther out.)

LorenDB 1y ago
I personally find the crosseyed type to be nearly impossible, while the parallel type are pretty easy for me. So I think it really depends on the person. Additionally, most stereograms I've seen (e.g. coffee-table books) have been parallel type.
- kazinator 1y ago
  The parallel types are also very easy for me, but they are always small. If the spacing between them is wider than my inter-ocular distance, I find them impossible to converge. I made stereograms in the past and wanted to see larger images with the naked eye, so I had no choice but swap the images and cross the eyes.
6yyyyyy 1y ago
I flipped them all, enjoy: https://imgur.com/a/OOiQ5AK https://imgur.com/a/OOiQ5AK (FYI: -vf stereo3d=in=sbsl:out=sbsr in ffmpeg.)
- entropicdrifter 1y ago
  Woo! The true solution!
pimlottc 1y ago

ge96 1y ago

For an example that works see this squirrel sorry reddit link https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2Fuphxv0t6wsw51.jpg%3Fwidth%3D640%26crop%3Dsmart%26auto%3Dwebp%26s%3D8a25f471fd9ee6a3b40016f5b6e2cf37fd2f5185 https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.... crazy but I feel sick now ha, I had a VR headset before and I'd get super sick trying to play FO4, VRChat wasn't bad

bredren 1y ago

Would be cool to get these converted into spatial photos for Vision Pro.

mdswanson 1y ago
Not too many steps away from this: https://blog.mikeswanson.com/spatial/ https://blog.mikeswanson.com/spatial/