Indigo Renderer Forum

This was a recreation of the pinhole camera experiment. A test, more than a work of art, but it was VERY cool seeing the inverted scene appear! I just made an enclosure with some colored shapes at one end, and a light source with another box at the other end. I left a very small square opening, and positioned the camera inside the dark inner box to try and catch any light reaching the inside surfaces. Here's the setup:



The normal view of the scene as directly lit, rendered with indigo looks like this:



And here is the image captured from inside the darkbox after 24 hours (not the fastest computer on the block though..)



It may not be pretty, but the image shows the physical accuracy of the indigo renderer. An even smaller pinhole would have left a sharper image, just as a real camera would, but the light reaching inside the box decreases exponentially. I'd love to see any other work that shows off not just the reflection/refraction of light sources, but also light reflecting off other surfaces, or possibly transmitted through a colored material, like a slide. It would be ridiculously slow, but I suppose you could even create a scene with a light shining through lenses to project a filmstrip on a screen!

I think I'll start playing with opposing mirrors next.

Holly ****!!!!!

Nice experiment KouOuKen.
The next step is to use a lens instead of a pinhole. This will allow more light to enter the aperture, while maintaining the focus. The tricky thing is getting the lens the right shape
Someone else did a similar Indigo experiment a while ago with a lens, might have been on the old forum.

Actually i have been vaguely considering using this kind of setup for the indigo camera model, because you would get stuff like real lens flare

WTF?
I tried the same months ago but failed
You managed it! congratulations VERY very cool!
i think i'll start testing again ...

Someone else did a similar Indigo experiment a while ago with a lens, might have been on the old forum.

I remember that thread. Incredible stuff.

Actually, here it is!:

http://www.flipcode.dxbug.com/board/topic/269/0/

You could make out the image in the pinhole camera after a couple of minutes. And the .blend files on the page still work! Check them out.

I would like to compare a pinhole camera scene between indigo versions - as it is one of the toughest physical benchmarks in my opinion.

Koba

ah, thanks Koba

T'was me (sorry, original pic has been replaced at the top of the image. I'll dig it out tonight).

Koba, mine used a lens instead of a pinhole. I want to get the shape of the iris in the next one, to produce that shaped glow.

I'm going to redo that one, as the lens is really out of shape (or has large problems).

I'll do some tests to determine the best shape for the lens using a sun lamp (also get the focal point).


The lens produces huge glow though.

Ah yes IanC - I was about to say that you used a lens but it slipped my mind while posting/finding your thread. Seeing you did the original indigo pinhole camera (with lens!) perhaps you could rerender the scene in several versions of indigo for comparison?

The prospect of using distorted lenses to create distorted images and perhaps lens flare is interesting. I'm sure a whole load of effects can be achieved by using a physically modelled, non-ideal camera. Try putting dust or water droplets on the lens for example.

I've always thought that a perfect camera always gets in the way of photorealism - especially in games.

Koba

Koba wrote: The prospect of using distorted lenses to create distorted images and perhaps lens flare is interesting.

I wouldn't say lens flare is caused by distorted lenses.
It's either caused by reflections of bright light sources (eg. the sun) off the interior surface of the camera barrel, or unwanted reflections between the different lenses in the camera. (or some combination of the two)

I'm not actually sure which one, I haven't found good information about this in the CG literature.

One more thing kououken:
I noticed the inside of your camera (the 'darkbox') has a high albedo (eg white) material on each surface. Try making the non-film surfaces black - this should reduce secondary scattering effects and produce a clearer image in less time.

Lens flare in real life is caused by light reflecting between lens elements, and possibly even the image sensor(for digital) back into the lens, even.

Manufacturers attempt to combat this with different lens coatings.

Simulating those, now... that would be a hell of a job.

In another note, I currently have a render in process, also, that is simply a test of the physical accuracy of indigo. (Currently at about 90h, around 200k[!] mutations per pixel, and counting)

As an example, I know that the Bi-Dir code is shaking its head right now, just trying to find a damn photon that the camera can see

Koba, sure. Probably not this weekend though, as I have friends down to see me.

I want to create a better version of it before I do though. Keep bugging me and I'll be sure to do it :p.

Ian

Wow its amazing to see what indigo can do. Great scene man.

I'm pretty sure you can use a plano-convex lens for camera obscura (in reality of course). One side is flat and the other side is convex (still spherical). Still very neat with the pinhole effect, I'm very surprised it worked!

scenes like this and the other one youve created with the glass tube and the single light really show off indigo's power.