Nuke Merge Node Transparency issue


#1

Hey guys so I don’t understand why when I merge these image sequences they work fine

but when I try to merge them with a background of a hill they become transparent

I am using non commercial Nuke on a windows 10 pro


#2

Here is what the merge node looks like


#3

Normally is caused by no alpha channel. Alpha channel tells Nuke what is transparent (black) and what is opaque (white). The merge over uses the alpha channel of your A stream to place it over your background correctly. So just make sure there is an alpha for your A stream by pressing ‘a’ while viewing it and check it matches your RGB channel.
If you don’t have one you will want to either re-render with a matching alpha if the image is CG or you’'ll need to manually create an alpha using either roto or keying for your plate in the areas you want kept.

Hope that helps.


#4

Okay thank you I will try that out!