So I have two versions of a texture, one is low res and contains an alpha channel, and the other is high res and is missing the alpha channel. I was wondering whether it would be possible to recreate the alpha channel on the high resolution version in Photoshop.
Low res version (with alpha channel)
High res version (no alpha channel)
To help, here is a link containing the .psd file: https://drive.google.com/open?id=1UYsFFK0RyJa0xmOfKBbSCR3rDiVNCLjG