i've discovered the colour settings in the edit menu to set a gamma 2.2 workflow. problem is i can't figure out where to set the gamma on imported images in my shader vops so they dont get corrected twice. any hints?

After your texture vop , add a pow vop and plug in a constant vop, set the float value to 1/0.454545 . To view your renders correctly set mplay gamma value to 2.2

Rob

mad. that worked.

I hope the linear workflow in Houdini gets improved a lot soon
A “linear / sRGB” switch with autodetect / autoguess (like SGI is most likely sRGB while EXR is most likely linear) during texture import or whatever would be a big step forward.

debris
I hope the linear workflow in Houdini gets improved a lot soon

God! I hope not. Workflow is perfectly clean as it is. Preset color correction on any color/image viewer and a whole internals made linear unless user explicitly wishes to change it (via gamma correction in a shader for example).

The way how mantra proceed with *.rat files could be managed more friendly (the way I mentioned here as an example), but that's enough. Less guessing, less troubles.


- http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=18139 [sidefx.com]

I hope the linear workflow in Houdini gets improved a lot soon

Have you tried maya & MR latey ? , Now that is a real mess. Houdini rocks !

I “tried” Softimage XSI the last 9 years

The linear workflow as it is there is perfect. Especially in a Nuke / OpenEXR pipeline.
As I'm not (yet) a Houdini user on a daily basis: is there any script or easy workflow to avoid de-sRGB-ing literally _every_ texture that goes into it by hand? The only things that go in as they are would be HDRs / EXRs, as they're already linear.

Looks like I still have a lot to adopt…

As I'm not (yet) a Houdini user on a daily basis: is there any script or easy workflow to avoid de-sRGB-ing literally _every_ texture that goes into it by hand

You build your shader once whenever you use a texture in your shader it gets the auto de gamma. The work flow is very easy.

To be honest this stuff should be in the basic shaders that ship with Houdini. along with more real world production shaders as what ships currently is not up to par with what productions use.

rob

circusmonkey
As I'm not (yet) a Houdini user on a daily basis: is there any script or easy workflow to avoid de-sRGB-ing literally _every_ texture that goes into it by hand

You build your shader once whenever you use a texture in your shader it gets the auto de gamma. The work flow is very easy.

rob

Sounds reasonable. Now if I can get it to filter the incoming textures by e.g. filename extension and _don't_ de-gamma files which are already in linear space (e.g. EXR and HDR) this comes close to the workflow in XSI.

Thanks Rob!

debris
Sounds reasonable. Now if I can get it to filter the incoming textures by e.g. filename extension and _don't_ de-gamma files which are already in linear space (e.g. EXR and HDR) this comes close to the workflow in XSI.
Thanks Rob!

The point is you don't want to render anything but *.rat files at all, and Houdini doesn't do it for you (Mantra does, but that's not an option). So linearizing is not a problem once you have to convert images to rats anyway. Workflow enhancement would be if Houdini starts treating *.rat as temp files, similar to prman or mental ray, and making auto conversions based on file's stat data. Ideally any texture call from within vex could trigger some action defined by a user.

For now keeping all *.rat files in sync with your source images, is tedious but easily script-able (and linearizing is just a small addition to a process)

SYmek
For now keeping all *.rat files in sync with your source images, is tedious but easily script-able (and linearizing is just a small addition to a process)

I know that pain. Same goes for Softimage and mental images .MAP files.

Personally, my beef is that it's 2010 now. We've hit upon the SECOND odyssey of Arthur C. Clarke. And we *still* don't paint textures such that they are saved in linear space to begin with.

I've got to be honest, I'm not even feeling particularly optimistic about the last in the series, either…

J.C.