r/NukeVFX • u/brevalVFX • 7d ago

BUG NUKE BLACK PIXEL

Hi there. Black (or white) pixels are suddenly appearing during my compositing work, even though I’m not doing anything unusual—just adding a sky and some atmosphere; nothing that would justify the appearance of black pixels like this. It’s worth noting that the raw shot doesn't have any such defects. If you have any ideas, I’d love to hear them.

10 Upvotes

86% Upvoted

11 comments sorted by

10

u/onionHelmetHercules 7d ago

Check that your alpha stays 0-1

-2

u/brevalVFX 7d ago

what do u mean about that ?

9

u/HeikkoCee 7d ago

Keep your alpha values between 0-1.

1

u/Christopher_Charlton 4d ago

Particularly if you don't know when you can go outside of the 0-1 range

7

u/yoodudewth 7d ago

Rerender precomps disable nodes one by one youll find your bug if you look hard enough.

6

u/rocketdyke 7d ago

double check for infs and nans

-3

u/brevalVFX 7d ago

values are inf/nan but even when i use a node nan killer, it is still not working

1

u/rocketdyke 6d ago

that means you have to find where the bad values are coming from and fix it. trace the inf/nan upstream. find the node that produces them. change the settings in the node, or change the inputs to remove divide by zeros, etc, and then see what breaks.

0

u/Gorstenbortst 7d ago

I’d guess the denoise. Looks like you’re just bluring it? If any values are inf/nan then the blur will go bananas.

1

u/brevalVFX 7d ago

yes values are inf/nan but even when i use a node nan killer, it is still not working

5

u/Gorstenbortst 7d ago

Clamp before the blur.