Divide by Alpha

The Divide by Alpha filter ensures the transparency in an image is stored using a non-premultiplied alpha representation.

If an image containing premultiplied alpha data (for use in other applications, such as compositing software and game engines) needs to be edited in Affinity Photo, first apply the filter to convert the data to a non-premultiplied representation. Not doing so may result in outline/halo effects or edges being too dark.

After performing your editing tasks, apply the complementary Multiply by Alpha filter to convert back to a premultiplied alpha representation.