Save a channel

[Jeff Kelley]

Just save a copy of your image and them delete all the layers you don’t want in the copy. You’ll have one channel in the image.

[Jeff Cochran]

You could try saving the file as a Photoshop DCS 2.0 file, This will create four different files. One for each color.

Jeff Cochran

https://www.jeffcochrandigitalartist.com/