Blue Channel

[MahaB82A]

I have watched number of video tutorials in YouTube. All is using blue channel only to remove background of an image. Is there any reason for that?

[D Fosse · Accepted solution]

When making a mask it's useful to look at the individual channels first. Sometimes one channel has very good contrast to begin with, so that it makes a good starting point for making the mask. Here it happens to be the blue channel, but it could just as well be red or green.

You see it a lot better if you turn off "show channels in color". It's really not very useful for anything, except it looks prettier in the panel 😉

[MahaB82A]

Thanks for the help.

[Stephen Marsh]

It depends on the image, but keep in mind that for JPEG compressed files, the blue channel will often have the most damage/errors from the lossy compression algorithm.

[MahaB82A]

Thanks for the additional information.