Photons

[Chenarch]

I got a lot of help last fall with photons from Dave (Archetype). I had a sample

project worked up of an empty room with an egg in the middle of it.

There was an area light at some windows (photons), a panel light in a room (photons), a sun for shadows (no photons).

I've gone back and studied that project. I can make tweaks and see changes and it seems to render quickly.

Now I am trying to do a bathroom with one area light at window (trying to bake photons). Total scene polygon count is 224,000. It is taking FOREVER. I have it going to a Nehalem machine running 10 cameras. Just trying to make a 320 X 300 test render.

I'm not quite sure I have it right. Is there any more written material on photons besides the Animator Manual? I will look for tutorials, too.

Thanks,

Richard

[Ian]

Hi Richard,

Can you post the basic scene for people to take a look at?

Or, can you post your light's photon settings/ GI settings

Cheers,

Ian

[Chenarch]

Yes, Ian. I will post the "test" file that seems to be working and is fun

to play with and will also post the difficult file of the bathroom that

makes my cameras "not responding". Try to do that later today.

Richard

Hi Richard,

Can you post the basic scene for people to take a look at?

Or, can you post your light's photon settings/ GI settings

Cheers,

Ian

[monday1313]

have you tried rendering it with less cameras?

[Chenarch]

Hi all,

Here is where I posted some more findings: http://www.chenarch.com/eias_bath_photons.jpg

It seems to be going well now...

The first set-up may have had some lousy geometry (the tub) which I fixed, then started the scene over. [Prior to that I was setting up two area lights w photons

and it would render forever and look terrible]. The scene is 24k polygons. First I got the sun and one area light working properly with quad dropoff at right distance (which Dave told me last fall). Establishing this first is important.

Then did photons from the window area light, then added an area light (to simulate a door behind camera) and gave that photons, too. The sconce lights and sun do not have photons. It worked pretty well after that, keeping Direct Lookup Radius at a reasonable number. I finally realized this number is like counting bricks. You can count bricks within a ten foot radius, but if you tell the camera to count bricks within a 150 foot radius it will bog down. At least that's the way I've been thinking of it.

Renderama was fine with it. A few quirks, but it always got back on track. With ten slave cameras on a Nehalem MP, this scene would render in about a minute or so at resolution 640. I put a couple of basic fast textures on it.

I'd still like to get shadows more pronounced from the sconces, but also trying to keep the sconce light to not get any brighter than this.

I'll post the other test with the room and the egg...

Thanks all!!

Richard

---

Yes forgot to say that I used GI w the baked photon maps but ONLY

as Reverse Illumination with One Bounce (no Sky Light).

I also had a World Global Reflection using Debevec's "Kitchen Probe".

Richard

[Chenarch]

Another thing I did.

In the first file, it was three walls. I then added a fourth wall to make it a contained

room and give the photons something to bounce off of. How relevant is that?

I don't know, I'm on a steep learning curve.

Thanks!

Richard

[Tomas Egger]

Hey Richard,

You are doing a fantastic learning curve, congrats!!!

About add a extra wall, its really important.. otherwise, you will have less photons flying in your interior scene, which can make appear artifacts (blotches), requiring more photons and slowing your render.. so, a simple wall, make your render beautifull with a faster render time, the second side Pro about a extra wall is the fact you will not have flicking light if you do animation.

Tip.. look more interior real photos to match your 3d rendering.. you will learn a lot reproducing them.

Congrats Again..

Thanksss

Tom

[Tomas Egger]

Hey Richard,

I was looking again.. is not the time to play with Light Objects? you can add 3 low poly spheres in the location of your 3 lamps above the mirror to emit photons light, It will become more and more realistic.

Thanksss

Tom

[Chenarch]

Hi Tomas!

Thank you for the good words. And thank you for the idea of the low poly Light Objects emitting photons rather than have them be lights.

Yes, will study. Dave (Archetype) got me going last fall, and now feel like

I'm back on track and the various controls are starting to make more sense to me.

Cheers!

Richard

Hey Richard,

I was looking again.. is not the time to play with Light Objects? you can add 3 low poly spheres in the location of your 3 lamps above the mirror to emit photons light, It will become more and more realistic.

Thanksss

Tom