At no point did I mention that the light source needs to be small and bright. Which is strange because the light source needs to be small and bright.

Finally a piece of content that actually uses the cross-eyed stereogram. It has always felt useless, aside from solving ‘find the difference’ challenges, but now I’ve finally used it again haha

That opaque square was trippy. I'm sure I've seen holograms that do the same effect, but this was on another level

As a kid in school back in the 70s one of the other kid's brought his mom for show and tell. She worked at a tech company, i think HP, and she brought in a few holograms she made with a laser on large sheets of acetate.

I remember reading about this technique in a science magazine 20+ years ago. The author of that article mentioned seeing this effect in the paint of a black car where a hand print seemed to be floating where the same hand had wiped the surface with a cloth but from two elbow pivot points.

Sitting here cross eyed watching holograms and then AHHH two Steves!

Never had good luck with the stereograms. Monocular vision really screws with that! But those holograms are FASCINATING! Just scratches and shiny, who knew!?

I'm blind in my right eye so when you started talking about the glint in a dirty windshield or the pot lid looking further away at certain points my mind was blown. I've never experienced that and never expected it was such a different experience for people with both eyes. It's always just been a glare to me. A smear. Never thought anything of it at all. I don't usually think much of being blind in one eye as it's all I've known but sometimes I get sad there's stuff I can't experience no matter what I do.

This makes me incredibly tempted to write some software to generate a CNC path that makes these.

This is how snow, or an icy road, sparkles: you get reflections off different ice crystals that your eyes interpret as matching, so your brain thinks there's tiny random sparkles of light at various distances including inside the surface of the snow/road/whatever.

I did this on a school metal toilet paper holder like 5 years ago. (For reference I have lots of experience making this kind of art) I put my name on it like an idiot. When I inevitably got called down to the principals office he wasn’t even mad about it he was just curious how I did it. So I showed him and after he asked me to make something for the school art show. I was given sheet metal from the shop class and I carved the schools logo into it. It wasn’t my greatest work, but for me at the time it was really good. I added my signature behind the logo so you could only see it from a specific angle. Also if you vary the line angles of different objects you can create 3d images with foregrounds and backgrounds. This is my favorite kind of art as you can create a 3D landscape in a 2d sheet. I also have messed with adding some color into the scratches on the surface of the image to give objects different colors.

Thank you for this!

I noticed this same sort of effect on scratched shiny surfaces like a car or counter. There are tones of random scrapes in all directions, but when light is shining on it the scrapes appear to be in a circular pattern around the light. It’s a really cool phenomenon and I never new you could do so much with it

Thank you so much for the cross-eyed 3d images, they were wonderful! I usually use this technique when photographing scenery or objects where seeing the actual depth makes a difference.

As soon as I saw the thumbnail and title I thought “Bill Beaty described this on his amateur science web site.” Glad he got a mention! Very nice explanation in this video.

I just tried it on an old CD "jewel box" case and it works! Amazing! So easy, yet so fascinating!!

Pair of compasses

Very cool idea to show the 3d-ness via stereogram 🙂 loving the content!

Not quite an interference pattern, but this does seem worthy of the "hologram" name - unlike all the Pepper's Ghost projections you see advertised as holograms. Love the way you can peek around the front etching!

My dad showed me how to do this when I was a kid in the 80s. He did some really freakin' cool ones. He tried to do laser holograms too, but he never got it working right.