Alpha Channel weirdness

Weird thing

2 layers
Top layer - has a alpha channel based on colour key in Color tab
Bottom layer - is a PNG (but also tried with a JPEG)

When I zoom (either in Edit properties or Zoom in Color sizing) the top layer down below 100% it reduces the frame of the entire comp...

In Nuke this was cause the top layer ref image size was linked somehow to the bottom layer....

Any idea what is going on?

thanks

Screenshot 2021-07-01 at 11.29.23.png (515.66 KiB) Viewed 984 times

Screenshot 2021-07-01 at 11.29.06.png (267.9 KiB) Viewed 984 times

Zoomed out top layer does not fill the area outside image with zero alpha and when keying black it results in alpha value 1.0, meaning no transparency.

OK- thanks
Let me check if I can fake a premultiply or add another layer ontop

If I key in fusion it works...

Try using a power window to isolate the top layer key. Resolve only creates transparency from the selected backing colour when on the Color Page. Everything outside the backing colour is solid unless cropped or masked. Personally I do all chroma keying with Fusion as it's a more complete toolset.