How to merge 3 images into a single one by RGB channels?

Question

I have 3 different images:

• for the first one I'm only interested in the RED channel;
• for the second one the GREEN channel;
• for the third one the BLUE channel.

My goal is to create a single RGB image composed by these 3 images filtering only the channels, so the new image will have to RED channel taken from the first one, the GREEN channel from the second one and the BLUE channel from the third image.

What is the procedure to do this in Photoshop?

Answer 1

Having as a base the Red channel image:

• Click the Green channel of the Green image, select all and copy
• Click the Green channel of the Red image, select all and paste
• Click the Blue channel of the Blue image, select all and copy
• Click the Blue channel of the Red image, select all and paste