Thursday, July 30, 2009

LWF

I've tried understanding linear workflow before, but never seemed to get over the hump. I think I'm finally grasping why people use this technique.

maya/renderman


It really bothered me that textures never render quite the same as I had painted them. I also use to wonder why using lights with linear decay looked better than lights with a physically accurate inverse^2 (quadratic) decay. Who knew I was just texturing and rendering incorrectly for the past 4 years- and why didn't they tell me? Now that I know, it's hard to sleep. I don't know if it's cause I'm excited or upset- or maybe it's just cause summer's quickly coming to an end :P

ps. coincidentally I used the same wood texture in this test as I used (incorrectly) for my floor in the previous post.

6 comments:

Francesco Giroldini said...

welcome to the club

Francesco Giroldini said...

oh, by the way, how do you change the gamma in renderman? do u simply render in openxr and apply a gamma correction afterwards?

rShow said...

I figured you were in on the workflow, you were actually one of the people I considered asking about this, but I was so confused at the time I wouldn't have known what to ask.

For this render I change the gamma to 2.2 in renderman while I was doing my test renders (Under the passes tab in render globals, the input on the right for exposure). Later I changed the gamma back to 1 when I did my final render to openexr. I didn't need to gamma correct it in post (as far as I know) because I was rendering to the openexr exposure and I had gamma corrected the texture before hand. When I convert the final render to jpeg or whatever the destination output might be, I just convert it and maintain the exposure I rendered the exr at. Does that make sense? Am I approaching it correctly? I worry that might be losing data but I assume if I keep everything 16 or 32 bit I'll be safe.

Next week I was going to see if there's a good way to create all my textures in linear space instead of gamma correcting them.

Francesco Giroldini said...

Yeah, the whole thing makes total sense inside mental ray, 'cause I don't need to gamma correct the textures, but inside renderman, it's just too much of an hassle to gamma correct all the textures... especially if a lot of your set is a matte painting...I'm still in the process of figuring out a good workflow for thesis.
I might end up just rendering in openxr 32 bit and fixing stuff in compositing afterwards..

Amalia said...

Wow. Thats a beautiful ball.... I guess I need to figure out what you're talking about asap. lol

Joon said...

This looks so realistic! How did you make it? :)