I have a set of images. One has a background that needs to be removed. Another is a pre-made alpha channel (white on black, grayscale to be precize as it has anti-aliasing). My goal is to save the image without background as PNG with transparency.
I was able to somehow paste the second image on the alpha channel. Now the background is red (indicating alpha-channel).
Now what do I do? I tried to save as .png but got an error saying that the alpha channel can not be saved in this format.
The background being red could indicate that a mask is currently being used with "Mask Overlay" turned on. Delete the mask and see what happens. To best use alpha channels, try "Clip Mask" on an object with an underlying image below it.