So i wanted to do some PS like editing with channels, I discovered the separate image option. (RGB)

I imported an image onto a layer, and then I separated it (image>separate image) checking the "output to colour" option. I'm not sure how to combine them back, I thought it was using screen blending mode? but when I use screen, the resulting image looks slightly different from the original image. I wish I could provide a screen grab, but I was hoping you can just follow the steps with your own image, or give me advice on the correct way of combining.

When you separate the image, the original layer is still there, so you can compare by switching it on and off. The main purpose of my experiment was to check if the actual RGB separation information is correct.

thanks.

Hm... How about, you try 'addition' instead of 'screen'.

You see, addition actually adds colour values together.
Screen, traditionally, is the inverted of 'multiply', which means that it well, inverts the values and then multiplies them. Which may lead to funny results.

hi, I tried addition and the result is still inaccurate. Perhaps its not the way to do it anyway? (via blending modes).

Hi,

To separate an image channels in separate layers, the way to go is:
-use the Separate image menu with the "output to color" option as you did
-then for each channel layer, go to layer properties and disable all channels except the one corresponding to the channel you want for this layer.

Ideally there should be an option to do this automatically, I think I made a feature request for this long time ago but I'm not sure..

I tried what you suggested yesterday, actually, but the combined result was still not accurate, this lead me to believe the separation wasn't accurate. However today I tried a new image, and the results where fine.

So, I really have no way of knowing what caused the issue, but right now it seems to be that particular image.

You are right, it should auto switch off the corresponding channels, no need to mess with blending modes then.

edit: just for reference, you can combine the channels by using screen. Its seems to be the correct way. It just wasn't working with the image I was using/