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Re: [REQ] hdr environment - gamma control

Posted: Mon May 20, 2013 6:08 pm
by William
Does changing the a parameter update the importance sampling of hdr?

Re: [REQ] hdr environment - gamma control

Posted: Mon Jul 01, 2013 3:43 am
by Zom-B
William wrote:Does changing the a parameter update the importance sampling of hdr?
A very good question, since I just have a scene here where changing the A value results in a firefly party:

A=0
A0.png
A=0.001
A0.001.png
A=0.01
A0.01.png
I haven't used Reinhard tonemapping here, but the Fireflies should be obvious anyway...

Re: [REQ] hdr environment - gamma control

Posted: Mon Jul 01, 2013 7:11 am
by CTZn
The question stands still, but the fireflies are more a consequence of augmenting the contrast (in short), wich make the sun into the HDR map more of a punctual source within a darker background.

In the other hand with a low contrast, the sun corona is playing an important role in 'smoothing' the rays transition around the very sun disc.

If only one single emitter is used (the background in this case), the question of the importance sampling between sources is irrelevant I'd guess.

Re: [REQ] hdr environment - gamma control

Posted: Mon Jul 01, 2013 6:10 pm
by galinette
Is this PT or Bidir?

This scene should be rendered with bidir.
The abc parameters may have not been taken into account in the importance sampling of the sky.

Etienne
Zom-B wrote:
William wrote:Does changing the a parameter update the importance sampling of hdr?
A very good question, since I just have a scene here where changing the A value results in a firefly party:

A=0
A0.png
A=0.001
A0.001.png
A=0.01
A0.01.png
I haven't used Reinhard tonemapping here, but the Fireflies should be obvious anyway...

Re: [REQ] hdr environment - gamma control

Posted: Tue Apr 01, 2014 1:34 am
by OnoSendai
I've added editing of gamma for HDR textures.