This is just going round in circles, the levels / auto-levels / pick a white point...etc is in the video here: https://www.gimp-forum.net/Thread-Filter...2#pid29432
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edit: A bit quicker than the video, a 30 second animation. https://i.imgur.com/vsANS6C.mp4 using the level dialogue. probably as good as you will get that negative.
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However if you have used the Gimp sequence for a negative image ➤ auto-white-balance ➤ Linear Invert then you have already applied a auto white balance (from the Colors Auto menu) and of course applying again does nothing.
Since you are not interested in using color curves, I was not going to bother with any more options. However, if you ever get round to batch processing those 1000 negatives the the gmic plugin temperature filter might work, easy to apply in BIMP. All depends on the negative. The new ones maybe too light.
Gmic on one image looks like this, makes sky a little blue, keeps the tree green-ish, this one never going to wonderful.
but might make others too blue.
best of luck.
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edit: A bit quicker than the video, a 30 second animation. https://i.imgur.com/vsANS6C.mp4 using the level dialogue. probably as good as you will get that negative.
--------
However if you have used the Gimp sequence for a negative image ➤ auto-white-balance ➤ Linear Invert then you have already applied a auto white balance (from the Colors Auto menu) and of course applying again does nothing.
Since you are not interested in using color curves, I was not going to bother with any more options. However, if you ever get round to batch processing those 1000 negatives the the gmic plugin temperature filter might work, easy to apply in BIMP. All depends on the negative. The new ones maybe too light.
Gmic on one image looks like this, makes sky a little blue, keeps the tree green-ish, this one never going to wonderful.
but might make others too blue.
best of luck.