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MahaB82A
October 6, 2024
Answered

Blue Channel

  • October 6, 2024
  • 2 replies
  • 644 views

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?

 

 

 

This topic has been closed for replies.
Correct answer D Fosse

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 😉

2 replies

Stephen Marsh
Community Expert
Community Expert
October 6, 2024

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
MahaB82AAuthor
October 6, 2024

Thanks for the additional information.

 

D Fosse
Community Expert
D FosseCommunity ExpertCorrect answer
Community Expert
October 6, 2024

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
MahaB82AAuthor
October 6, 2024

Thanks for the help.