Resolume Forum

I am wanting to use a transparent still image ( a .png from Photoshop) to partially mask the clip below but I can only get a blend of the two images. Is it possible to use a still image with transparency as a mask and if so does anyone know how to do it? Thanks.

First of all, if you have a png picture which you want to see, and that png has transparent areas where you want to reveal the layer below then:

• On the clip Video properties tab you should see that the png has RGBA channels enabled,
  If the A is gray and can't be enabled then you have exported the png without alpha channel.
  If it is enabled, then most likely your background which you would like to be transparent is not.
  
  There is a very useful plugin for making the black background of a clip transparent called Automask

If you want to use a png as a mask to black out some areas of a layer then see how to use masks here: https://resolume.com/manual/en/r4/masks

Thanks for the quick response. The still image is showing transparency in the preview window (you can see the grey-black chequer board showing in the transparent areas of the image) and A is active. Therefore I am assuming that the imported image is indeed transparent but when I try to composite it, I can only get blends and not the lower image appearing in the transparent parts of the "transparent" still image as I had expected.

try setting the png layer blend mode to alpha and the layer opacity slider fully up.

Also check the alpha setting of your PNG with RGBA channels (straight vs premultiplied) and make sure it's set right.

The layer opacity slider was the problem, moved it up and there the clip was was! All sorted, thank you very much for your help.

Thank you Oaktown and ravensc for your help with this one.