Looking through the examples I noticed that B and G had a colour cast
similar to the colour produced by the filter on colour negatives. Some
months ago I spent some time turning colour negatives into a digital
form and then processing them in GIMP. Having got the original RAW
images I had a look to see what Restore could do. The results are most
encouraging and could lead to another use of the plug-in.
It is really very simple. Take the image of the colour negative and
apply Restore at the default settings. Then choose Colours -> Invert and
the positive image is there.
I suppose there is no reason why the invert step could not be
incorporated into the plug-in as another option.
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