Issue with After Effects mask expansion


I have created an animation in After Effects with a cut out ellipse mask moving around the screen which eventually expands. It works great in After Effects but when I try to convert it to a Lottie file the expansion doesn’t work correctly. As the circle expands there is a second, non-transparent ring inside.

You can see the video on YouTube and the red circle is the transparent mask.

This is the Lottie

Can you share the link to the lottie so I can compare?

I also have an issue. I keep getting this issue when I try to render, however I do not have a mask expansion in my animation? I don’t understand where this issue is coming from. Any tips/help is very welcome <3

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Can you share the After Effect files so it would be to understand the issue?


ive made a link here. It is in the folder ‘ANIMATION’ and the composition is called ‘V02’
Hope you can help! Im so confused about what I am doing wrong.

Hey, thank you, @nikki for sharing the file. I went through the file and I exported using Bodymov in plug-in here is the result. I compared the After Effect animation and exported Lottiefile animation, I don’t see any issue.

oh thank you so much! that is both a relieve and frustrating at the same time! I keep getting the issue ‘masks expansion’ But I don’t know what it means / where this problem is in my animation.
Do you have any idea about what masks expansion could mean?

I will also try exporting through Bodymovin though :slight_smile:

Me either don’t know what does it mean. :grinning:

alright. Thank you so much for checking!

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Are you saying that it gives you the error when you’re exporting and it shows the check list? If so, you can almost ignore that if you’re not seeing a specific error when previewing it. I sometimes do that

I’m having the same issue! I am getting an error when I try to export as a lottie.
I only utilized mask paths for my animations. I did not use a mask expansion, but the error that I receive is saying that I used a mask expansion and that it’s not compatible with ios/android etc. Can anyone help please

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This original suggestion won’t work for your case unfortunately my fault for suggesting it. another possible workaround you could try is to use track mattes instead of masks.

(original message)
Hi Nikki. Check for any “merge paths” on the shape layers that you are using and delete the merge paths. This may help

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Your solution here

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