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Trench117
24-09-2016, 10:31 AM
Is there a reason why Catalyst adds a black edge around content on 4444 files?

It looks like aliasing on curved edges that is turned black rather than transparent.

Cat v5 n561.
samsc
26-09-2016, 10:26 PM
show a screen capture?
did you use non-premultiplied alpha?
how you make the image?
samsc
26-09-2016, 10:27 PM
show a screen capture?
did you use non-premultiplied alpha?
how you make the image?
Trench117
27-09-2016, 10:26 AM
It is straight Alpha out of C4D, ProRes 4444. I am looking at the darker edge around the DNA strand.

Thanks,

852
samsc
27-09-2016, 09:28 PM
you need to show me exactly what happens to colour and alpha channels at that point
Trench117
28-09-2016, 12:40 PM
https://www.dropbox.com/sh/76hcxijjdsp21ct/AAB47zOHHoTfvkR8uQ74UV_da?dl=0

pass: alpha4444

File 088 is the Alpha file which is over a live camera input.
samsc
28-09-2016, 02:42 PM
https://www.dropbox.com/sh/76hcxijjdsp21ct/AAB47zOHHoTfvkR8uQ74UV_da?dl=0

pass: alpha4444

File 088 is the Alpha file which is over a live camera input.

is your movie straight alpha or pre-mulitplied?

http://www.provideocoalition.com/alpha-channels-premultiplied-vs-straight/

and have you checked the c4D output?

http://mograph.net/board/index.php?showtopic=28526

"Isn't Straight Alpha better...? in C4D it renders out a little extra edge of the colour of the object so when you bring it into AE there's less chance of getting black edges where transparency should be. Correct me if I'm wrong."