Clamp/Emission Material/Compositor

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Racleborg
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Clamp/Emission Material/Compositor

Post by Racleborg »

Hi

When setting up an Emission Material (ID) with the Compositor, it all works fine without clamping. But when I set the Suggested Clamp Value, then it doesn't appear to work at all?

Thanks
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B.Y.O.B.
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Re: Clamp/Emission Material/Compositor

Post by B.Y.O.B. »

Scene and/or some screenshots please :)
Racleborg
Posts: 621
Joined: Sat Apr 07, 2018 10:31 am
Location: UK

Re: Clamp/Emission Material/Compositor

Post by Racleborg »

B.Y.O.B

Link to scene https://1drv.ms/u/s!AhdwgLaw01tLjxEZ2ZGfWtp3oFGm

Images attached.

Thanks
Attachments
Clamp Off.JPG
Clamp On.JPG
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B.Y.O.B.
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Re: Clamp/Emission Material/Compositor

Post by B.Y.O.B. »

Looks like the suggested clamping value is too low.
Try higher values.
Also, you might have to lower your glare thresholds in the compositor a bit if you use clamping.
Racleborg
Posts: 621
Joined: Sat Apr 07, 2018 10:31 am
Location: UK

Re: Clamp/Emission Material/Compositor

Post by Racleborg »

B.Y.O.B

Thanks, I'll try that out later today.
Racleborg
Posts: 621
Joined: Sat Apr 07, 2018 10:31 am
Location: UK

Re: Clamp/Emission Material/Compositor

Post by Racleborg »

B.Y.O.B

Is there a best amount of time rendering to set the Suggested Clamp Value. It appears to change a little bit over time?
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B.Y.O.B.
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Re: Clamp/Emission Material/Compositor

Post by B.Y.O.B. »

No, it is estimated once after 10 seconds.
In the most recent code it was changed to run once after 2 samples I think.
Racleborg
Posts: 621
Joined: Sat Apr 07, 2018 10:31 am
Location: UK

Re: Clamp/Emission Material/Compositor

Post by Racleborg »

Hi B.Y.O.B

I seem to have been fighting against myself/a typical Catch 22:

Up the light strength to drive compositor, but to reduce the fireflies I have to clamp, and just when the fireflies are gone then so are the compositor effects, so I up the light strength etc etc......

And the above has been the same whether I use a Material ID or the Light group in the Compositor.

That was the bad news. The good news, which appears to be working great, is to render the scene (clamped) then render the effects (not clamped) then mix the two together! :D :D
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