# Stereoscopic images

Disclaimer: I know this is probably the complete wrong place to ask this. But seeing as there is no Tattoos.stackexchange I will give it a shot because at its core, this question is down a photographer's alley.

The meat and patatoes:
I recently have come across the idea of stereoscopic 3d tattoos similar to the image below. I was wondering if someone could educate me aboutt how stereoscopic images work and if these tattoos can be viewed this way (on flesh). Also, how is "modern" 3d that is viewed via polarized lenses work (Avatar)?

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Thais ia an Anaglyph – Itai Jun 6 '12 at 1:52
And it is wrong. The superimposed areas should be purple (red plus blue) or similar, because otherwise you'll see an incomplete image – clabacchio Jun 6 '12 at 9:25
Awesome idea for a tattoo, just a shame it doesn't work in this case – Dreamager Jun 6 '12 at 12:35
What a time to get it wrong... – rfusca Jun 6 '12 at 14:56

The idea behind stereoscopic 3D image is to present to each of your eyes a slightly different image. Your brain will (try to) interprete the two images as being two different viewpoints of the same object and deduce the third dimention (depth).

First you need a way to let your eyes see 2 different images.

• The simplest is to use a device which allow you to see different image (this is call a stereoscope).

• You can also place two (small) images side by side and educate your eye to look "behind" the screen as it is the case for autostereogram http://en.wikipedia.org/wiki/Autostereogram

• You can achieve it by colored lenses (this is the case of your sample pic: a blue and a red glass. Through the red glass you can see only the blue image and it looks black and through the blue glass you see only the red image)

• Another way is to have a screen presenting alternativally the right and the left image and glasses which sychronouzly hide one or the other eye.

• You can also use polarized light and discriminate which part of the image goes to each eye with polarized filter

My guess is that in the case of a print (on whatever surface) you are restricted to the side by side images or the colored ones

Having choosen the technic how to produce the images? look through a window: closing an eye you can superpose on the window a drowing to the underlying image, now (without moving the head) switch eye and start again: you have your two image to be combined: of course you may take photography (replacing your eyes with camera) or use computer to project the 3D object on the window plane

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