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stevenpalomino
10-12-2010, 09:14 AM
Hey all,

I couldn't help but notice that there's an image filter that says "gamma" in the layout processing tab.. would this be the same as the LW 10 linear workflow? Or is there a difference here?
thanks!

Tobian
10-12-2010, 11:37 AM
mostly yes, but not quite. Processing sRGB images to linear gamma is 'roughly' the same as a 0.4545 gamma. That has it's problems though, because 1) it can cause stepping, if you then apply the display gamma (the image filters throw data away, like it would in Photoshop) and also, because that conversion is only approximate. LW10 allows for custom lookup tables for more accurate image profile conversion.

Linear Gamma has 'technically' been possible within LW for quite a long time, since it supported saving out floating point images, the new additions just help make that process less of a pain!

silviotoledo
10-12-2010, 12:26 PM
well..... I've seem Matt cool video that explains the theory about Gamma, but I'd like to see a tutorial step by step about how to use this tech. Any link?

I mean:

How do I de-gamma images and collors in lightwave?
How do I reaply gamma at the end?

Silvio Toledo

Skonk
10-12-2010, 12:29 PM
As in stands now I think it's just a case of manually adding the Full Precision Gamma filter to all your images in the image editor; and using it to de-gamma all your textures.

Then adding the Gamma image filter from the image processing tab to re-gamma the final image.

speismonqui
10-12-2010, 03:33 PM
well..... I've seem Matt cool video that explains the theory about Gamma, but I'd like to see a tutorial step by step about how to use this tech. Any link?

I mean:

How do I de-gamma images and collors in lightwave?
How do I reaply gamma at the end?

Silvio Toledo

:agree:
I want it too!

Tobian
10-12-2010, 04:35 PM
I think Gerrardo goes into some of this in his tutorials on HDRI magazine

http://www.artstorm.net/journal/2009/08/color-management-workflow-cg-3d/ Artstorm also goes into it, in great detail...

I also go into it in my 3D world video tutorial, but my way is not 100% correct! :D

Sadly, with respects to LW 9.X there is no one or a simple solution to it, and

rsfd
10-12-2010, 05:35 PM
well..... I've seem Matt cool video that explains the theory about Gamma, but I'd like to see a tutorial step by step about how to use this tech. Any link?

I mean:

How do I de-gamma images and collors in lightwave?
How do I reaply gamma at the end?

Silvio Toledo


:agree:
I want it too!

Easiest way: download Mike "Lightwolf" Wolf's db&w Tools (http://www.db-w.com/content/view/137/175/).
You'll find the "Simple Color Corrector" as Node, Image / Pixel Filter.
You can linearize colors and images and you can use the Pixel Filter for previewing purposes on F9 renders (to have a "gamma-encoded" image in ImageViewer).
If you render to a linear output for post-production, you should turn off the Pixel Filter for final output.