Picture Repairs or Cleaning: Paintshop Pro or other editors.

[zorin]

Originally Posted by VintageKell

Extra Thought:

While I was in the pub last night I thought about this issue and Zorins post, and had a question.

Is it possible to replace the blue channel (in the example we are discussing), with one of the others ....renaming it 'blue' and changing it to blue?

That wouldn't do much good since you would loose all the blue image data from the image and simply duplicate all the red or green data depending on which of the other two channels you would choose to copy.

The channels in an image file each hold (greyscale!) image data for one of the colour channels (primary colours in case of RGB) which make up the total image.
No I'm not kidding, a colour image file actually only contains greyscale data. The actual colour image is created by the graphics card in your pc and the monitor attached to it.

As an experiment I tried something similar in photoshop though instead of copying one of the other channels I tried to replace the original blue channel data with the edited copy of the original blue channel. Photoshop threw me into CMYK mode with an image containing only two channels which looked absolutely awful and which I threw away as quick as I could in order to prevent permanent damage to my eyes.

As far as the colour banding problem is concerned, I too tried a few other things first before turning to the dodge and burn tools and using them on the red and blue channels.
Ideally I would have wanted to use a mask for each of the annoying colour band patterns and use them to remove the colour bands by using them in combination with a colour adjustment layer. Unfortunately I was not able to find a quick enough way to create a mask for each banding pattern so I abandoned that idea.