vraySKY and gamma correction

[pailhead]

I'd like to hear a way around it

[ene.xis]

id like to see some pics

i know i m wrong now...and i d like to see it adressed, as i m sure it will, but i d really like to understand how wrong am i!

[pailhead]

I don't really know how to create a picture that would illustrate the problem, but you can see how different is the sky map when you use the gamma correction, and when you don't. With the gamma cranked up, the sky is kinda washed out.

Place a vray camera anywhere in the scene, set up the vray sky +sun system. Render once, and then turn the gamma correction on and off, you'll see the difference.

[pailhead]

Will this issue ever be addressed? I would like to use my gamma curves, but still have a nice vivid sky...

[voltron7]

what version are you on? This seems strange. Usually I can have pretty good control of the sky by adjusting the phys camera. Maybe your gamma setup is off a bit?
Another way would be to tick the manual sky check box in the Vraysky map., then you can adjust the sky's controls independent of the sun...not sure if it will help, but good luck.
and yes, maybe watch LeLe's tuts...

[plastic_]

to archive a different gamma curve for the visible sky you can simply use colorcorrect with the vraysky map as max environment.
use the original sky in the vray GI environment override slot.

[pailhead]

Same problem, a bit more elaborated:

http://www.chaosgroup.com/forums/vbu...ad.php?t=41947



This is what vraysky looks like to people who are not in the LWF sect:



But after they transcend through extensive use of mystical and magical gamma curves, the followers of LWF change their perception, and this becomes the One, the only, the True Vraysky. Blinded by their faith in sRGB space, they now deny the sheer existance of the previous instance, the lesser deity, the gamma uncorrected vray sky, which now has a dark, unholy and oversaturated aura around it.









Color correct does not work, it totally messes it up.

[ruud3dv]

But after they transcend through extensive use of mystical and magical gamma curves, the followers of LWF change their perception, and this becomes the One, the only, the True Vraysky. Blinded by their faith in sRGB space, they now deny the sheer existance of the previous instance, the lesser deity, the gamma uncorrected vray sky, which now has a dark, unholy and oversaturated aura around it.

LOL! love these LWF convs

But sRGB and Vraysky with gamma correction makes sense:

Vlado:

The color transformation that V-Ray uses for the physical sun and sky and for the VRayIES lights is closest to CIE RGB color space. When you add gamma correction, this becomes close (although not exactly the same as) sRGB color space.

[jujubee]

Pailhead is absolutely correct with his results. The Vraysky becomes extremely dark when using LWF with exteriors if followed properly.

I am still waiting for some confirmation from Vlado regarding the use of LWF on exteriors and how to go about resolving this.

I believe this issue lies more with the actual gradient maps the Vraysky software employs.

[ruud3dv]

Actually in his post he is stating the opposite, that a vray-sky would look too washed out when using LWF.

Some more discussion about this and some test-examples in this thread:
http://www.chaosgroup.com/forums/vbu...ad.php?t=41947

[ene.xis]

The Vraysky becomes extremely dark when using LWF with exteriors if followed properly.

i disagree!
from my experience it tends to look just a notch unsaturated imo...

[jujubee]

My mistake. I need to reread his posting.

[ene.xis]

i think there are some misleading interpretations floating around and setting up ur materials correctly(er) has a major influence in all the workflow since the exposure of the camera itself will influence the sky!

[Shimakaze]

i think there are some misleading interpretations floating around and setting up ur materials correctly(er) has a major influence in all the workflow since the exposure of the camera itself will influence the sky!

Yea, there are a ton of misinterpretations of LWF.
Man someone should really post a comprehensive FAQ sticky.

[rmejia]

Here is an interesting thread about gamma correction going on at cgtalk:

http://forums.cgsociety.org/showthre...7&page=1&pp=50