4 replies to this topic

[gradualepiphany]

I've found an odd bug using the over function inside of the Composite cop - I've got Image A over Image B - A has an alpha channel, B's alpha is completely white.  Even if I HSV or Bright A's alpha down to complete black, A will still be about 60% visable.

Any ideas?

thanks,
|andrew|

[tallkien]

Yup i'm getting it too (175,linux), you should post this at SESI, they'll want to know about it.

Same with the Layer cop

EDIT: Works fine if you leave all 4 plane scope buttons toggled "on" and type "A" explicitly in the field next to it instead of * . Still not sure if this a bug or intentional, don't remember it being like this before, Can someone confirm

[anakin78z]

Try adding a premultiply cop after you bring the alpha down.  I think most compositors function that way if the A image isn't properly premultiplied.  

Cheers,
Jens

[tallkien]

premultiply does it, thanks

[gradualepiphany]

DOH!

I should have known that.

thanks much

|andrew|