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.)
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.
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.
I flipped them all, enjoy:
(FYI: -vf stereo3d=in=sbsl:out=sbsr in ffmpeg.)
Woo! The true solution!
You can flip images horizontally via CSS:
img {
transform: scaleX(-1);
}
javascript:(()%3D%3E%7B%5B...document.querySelectorAll(%22img%22)%5D.forEach((e%3D%3E%7Be.style.transform%3D%22scaleX(-1)%22%7D))%3B%7D)()%3B
That is very clever, and useful, thank you.
But it doesn't achieve the effect we are after at present.
When we reflect the stereogram left to right, the orientation of the parallax recorded in the images also flips and so the net effect is zero: if the original stereo pair is a stare-into-the distance stereogram, the reflected stereogram is also.
Ah, good point. I wonder if it's possible to achieve the left/right swap in CSS? Alas I am not a CSS guru.
For an example that works see this squirrel sorry reddit link
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
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
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).
The cross-eyed method requires the images be swapped left-for-right.
Not sure why you are downvoted; that is correct.
Create two pictures from it and use https://huggingface.co/spaces/cavargas10/TRELLIS-Multiple3D
Would be cool to get these converted into spatial photos for Vision Pro.
Not too many steps away from this: https://blog.mikeswanson.com/spatial/
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.
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.)
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.
Yeah, if there is depth, it was pretty subtle on the few I got to work.
Here are some videos trying to show what I mean. I overlapped the two images on top and crossfaded between the two. Aside from some minor distortion I don't see any major differences normally found between stereo pairs.
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.
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
I agree that particular image is a dud; I was not able to perceive any depth.
The creator mistakenly used the same image twice.
The two men in a tent image is likewise a dud. If we look at the pole at the tent entrance, there is no difference in parallax between that and objects at the back wall.
The Abe Lincoln doesn't pop out much for me.
The dead soldiers in the field also seems to be identical images.
The clearly genuine ones are the horse-drawn carriage in the forest, and the horseman in front of the cannon.
[dead]
