I have scene with emissive volume and no density rendered in Karma which is being comped over footage. Issue: since its emissive transparent pixels I was unable to replicate the exact look in AE. Currently ignoring the transparency and using screen blend mode. I have read about straight and premul alpha, but couldnt implement these findings.
I know its impossible to have volumes emit light, while not blocking any light, but it would save a ton of time to render without density.
Anyone stumbled upon this and found elegant simple solution?
Essentially I want to have at least some sort of see through edges and full opaque volume inside dense areas.
Thank you very much for any help, I might want something impossible, but that's where creativity comes
if you render pure emissive volume it will have no Alpha, which is correct and it will also not block any other light
the comp should be simple, just Add over the plate, not sure how it's called in AE, in Nuke is called Plus Assuming your soft assumes the image is already premultiplied (which it should) you can also use Over, since if Alpha is 0 then over is the same as Plus: A + B(1-alpha) = A + B(1-0) = A + B
tamte Assuming your soft assumes the image is already premultiplied (which it should)
Yes thank you, the issue was AE I was unable to premultiply it correctly with all permutations of interpreted alpha + Extractor + OCIO transform... I rendered density and just used it as matte with some tweaking. I am transfering to Nuke very soon
