Hello!
I'm sure all of you know this usefull tool. My problem is that I cannot force it to work with hdr images - thought such possibility is mentioned in doc. When starting script i can't see any cops in H., so i've created my own, loaded tiff file and… futher steps go from intuision , and rewired sop OUT to map_image sop (not sure about this name). and… it does not work.

Another question is a script generated from lightgen plugin. Scenes produced by this stuff is so slow to render that i cannot see reason to use this metod, which is supposed to be faster then GI.

As you see everything goes to question about aproach on realistic lightning in Houdini/Mantra. Maybe one expirienced person would writedown few words about this issue. I cannot deal with mantra in it. Should I try PRMan?

I can't see why you can't deal with it in mantra. Have you read the Global Illumination tutorials in the help? Click on the question mark in the top right corner. Then choose User Guide Contents > Lighting > Global Illumination. The last section on that page deals with Image-based Illumination which discusses how to use hdr files for rendering.

no, no
GI based on materials and tut. from SESI are great, everything works fine, no problem with this, but Iam interested in go around GI in Mantra, since it's not a deamon of speed… even ambient occlusion is quite slow. I preper few shots in which i have to add buildings to exsisting architecture.

I was just interested how the others deal with such a task in houdini/mantra. Iam new in it, i use to work on LW and it wouldn't be a big problem to do it in LW. Problem is that i still cannot achive this level of realism in Mantra that i got in LW, so - i expect - my fault! and i wonder how to do it correct…

I use hdr for reflection, skydome of lights for ambient light, spot for key. I would like to use hdr to give a color to lights in skydome also - and from that had began my question.

Thanks.

symek

so maybe the lightgen plugin for HDR shop is what your looking for

http://www.ict.usc.edu/~jcohen/lightgen/lightgen.html [ict.usc.edu]

For your shot, have you tried to see how low you can lower your number of samples in ambient occlusion while still getting the expected quality?

well as I wrote earlier scenes generated form lightgen plugin render so slow that i left this possibility.

As to samples, minimal value of it in ambient occlusion is something about 512 - which drive me crazy…


I still work on global script (i had old version), so maybe i will force it to work with hdr images.


thanks for help.

symek