Questions about shadows and lighting.

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Old 02 February 2004   #1
Questions about shadows and lighting.

I really love accurate soft shadows. They are just so damn sexy. Area Light shadows in Lightwave produce some really nice results. They can be a little grainy and take a long time to render but I like em.

I'm trying to see how I can get the same look in Studio.

So here is my image from Lightwave. As you can see. . . nice soft area light shadows and a little Global Illumination. It took around 4 minutes to render.



Here is my first image from Studio. This is using the environment material at .75 grey. As you can see it has a lot of potential. It only took 35 seconds to render and has all the GI and sexy soft shadows a man could want. Only. . . there is no particular light source.



As you know lights in Studio can only cast hard raytraced shadows.



So I had this FANTASTIC idea! Why not use Messiah's amazingly cool GI to "fake" an area light. Just have a single polygon set to a high ambience and allow it to emmit!



And. . . as you can see. . . that didn't work either. The emitting surface spit out some really really grainy blobs of light in a very harsh way. And no GI was calculated from that emitted light. I don't really understand why. Anyone have any ideas? It seems like this should work. . .

Last edited by Wegg : 02 February 2004 at 06:35 PM.
 
Old 02 February 2004   #2
Here are my settings. . .

 
Old 02 February 2004   #3
Re: Questions about shadows and lighting.

Originally posted by Wegg
As you know lights in Studio can only cast hard raytraced shadows.


messiah:studio has area lights (called "Panel" lights, and "Sphere" lights). Set your light type to either panel or sphere, enable raytrace shadows, and you will get soft area-light-like shadows. Area light quality can be set in the light settings block.
 
Old 02 February 2004   #4
Re: Questions about shadows and lighting.

Originally posted by Wegg

As you know lights in Studio can only cast hard raytraced shadows.



I think Area lights cast soft shadows.

edit: Doh! Simeon got there first.
 
Old 02 February 2004   #5
Huh. . .

Why couldn't I find that. . .

And why wasn't it in the manual. . .

And. . . where is this light settings block?
 
Old 02 February 2004   #6
Oh wait there it is. . .

Cool.

4:43 minutes AA level 4



Is there a Shading Noise Reduction anywhere?

Last edited by Wegg : 02 February 2004 at 08:58 PM.
 
Old 02 February 2004   #7
Nope, but there is something to come I believe...

M.
 
Old 02 February 2004   #8
Wowa. . .

Increasing the Anti Alias level made it worse. Now the AA is at 5.

And. . . what are these dots and cunks?

Last edited by Wegg : 02 February 2004 at 08:58 PM.
 
Old 02 February 2004   #9
Hey Wegg,

Could you post the scene file, preferably in .mpj format.
__________________

 
Old 02 February 2004   #10
Here ya go.
 
Old 02 February 2004   #11
Wegg, what cpu are you running Studio on ?
__________________
Regards,

ALan
 
Old 02 February 2004   #12
Dual Athlon MP
 
Old 02 February 2004   #13
Well, Wegg,

I see that you're working on a medical animation project. You've left some brain surfaces in the file.

I can confirm your findings ... seems a bit strange that increasing the AA would lead to grainier shadows.

The chunks you see is a delineation between what is in raytraced shadows and what's not - usually at the junction of polygons. Haven't seen those since my Imagine days. Here's a page on that issue I wrote back in '96/'97. Man, how time flies when you're having fun.

http://www.3ddmd.com/polyartifacts.htm

Supposedly, messiah:studio renders SubPatch/MetaNurbs objects without going through the tesselation process - but it still displays seams at "star" junctions or where more than 4 splines intersect.

http://www.cgtalk.com/showthread.ph...ht=test+renders

This is supposed to be addressed at a future release. Unchecking "Self shadow" is one partial solution, but if the object has something like a tentacle then it's not going to be accurate. Hopefully, the polygonal shadow artifacts will be addressed as well.

__________________

 
Old 02 February 2004   #14
If you make the default surface reflective ( say 0.5 ), when Studio does its 2nd rendering pass, it smooths out the blotchy area shadows on the polygons, as it should, but leaves the reflected shadows ' noisy ' looking....
__________________
Regards,

ALan
 
Old 02 February 2004   #15
WOWA!

Throw the area light quality up to 10.

It looks better and renders in LESS TIME!

3:14 instead of 4 somethin. . .



I'm goin for 20. . .
 
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