Mask subtract mode in AE not working on random frames

I made a mask in Mocha Pro and then selected “Create AE Mask” to add it as a mask to the layer. I then selected the subtract mode. However, on random frames the mask is not subtracting. The mask is there but the layer is unaffected. If I enlarge the mask in AE on those problematic frames, the subtraction takes effect. But it is a rotoscope and I need the size to be exact. Is this a bug? This is happening on multiple different layers in my project.

Check your shape in Mocha, it may be that you have perspective on that rotoshape on and the surface is going behind the camera. If the shape is a problem in Mocha it will be a problem in AE. But if it’s not subtracting properly in AE, that’s an AE bug and not a Mocha bug. Once it leaves Mocha and is made into an AE mask it’s a native AE mask.

Let me know more and I will be happy to help you!

Thanks for the immediate reply!
Perspective is not on in Mocha.

If the mask looks right in Mocha but isn’t subtracting consistently in AE it’s an AE problem then. Make sure you have the layer set to subtract. If it is set to subtract and just isn’t subtracting consistently, this might be a better question for the AE forums.

Got it. Thank you!