Working camera-obscura in Cycles (proof of physical correctness)

Artwork Blender Tests
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I’ve wondered, how physically correct is Cycles, and set a simple experiment. I’ve built a camera-obscura in blender, very basic type of camera. But it has optics at least. And this modelled optics worked!

The image below is rendered without any tricks or fakes. (I’ve added some freestyle outline to show the camera, because the scene is totally dark). My first real-word camera obscura worked much worse :slight_smile: Аnd yes, I had too much free time today.

obscura-test-01.png960×540 16.6 KB

What is camera-obscura: https://en.wikipedia.org/wiki/Camera_obscura
Blend file: http://www.pasteall.org/blend/37209 (see? see? just black box, lens and translucent glass!)

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It works even if you delete the lens object. And the hole aperture controls the focus. Cool!

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That means, that emulated light is more coherent, than real one (probably, different wavelengths are not emulated)

4

And using the new light portal from 2.75, will speed up the convergence :wink:

5

It’s included in regular build now? I thought it’s for environment lighting only.

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Yah, it’s already in the RC. And what it helps is to throw more rays in the portal direction, as if it was a light. In the case of a camera-obscura, the rays that come from the pinhole are the only we need.

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Beautiful! Would be nice to see the same render without portal.

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With control of an aperture diameter and thickness you can get some very sharp focuses in the real world, Although every loss of roundness and flatness of the aperture is going to hinder that.

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Follow the link - the render without portals is on the other thread.