Color correcting photographs from the 1970s?

okieman · June 18, 2023, 10:19pm

I have digital scans of a number of photographs taken during the 1970s. By the time the scans were made, the usual color shift had already begun: blue and green faded, and lots of reddish brown in shadow areas. Two questions:

1-I use GIMP and RawTherapee. Is there a specific color profile or set of instructions for these kinds of software to color correct my 70s photos?

2-For situations where there is no blue or green remaining to be salvaged, what are some of the better options for salvaging 70s photos?

Terry · June 19, 2023, 12:06am

I sometimes have incredible success restoring faded colors using just auto levels in GIMP. I also have good results on occasions using the color calibration module in Darktable. I don’t use Rawtherapee much, but I am sure that it would have some similar options to neutralize color balance. Can you share one of your images where you feel there is no green or blue left?

okieman · June 19, 2023, 12:35am

Here is one from my mother’s family, which is mostly missing green…

Terry · June 19, 2023, 1:22am

Yep, this ones defeating me so far. It would be interesting seeing what others could do with it. What scanner are you using. Sometimes the color fade options can help during the scanning, but probably not with this one.

okieman · June 19, 2023, 2:59am

This image was scanned so long ago that I don’t even remember.

I suspect that some of the companies that do restoration are using talented photo technicians to colorize. Maybe I should just wait until “AI” can handle this type of problem.

Terry · June 19, 2023, 5:19am

AI can already fix these problems, but the only services I am aware of cost money and with lots of images the cost could soon add up. Even B/W images can be colorized.

Thomas_Do · June 19, 2023, 9:35am

Edit: Second try.

Still some things to be improved, but there is potential.

test.jpeg.xmp (10.3 KB)

s7habo · June 19, 2023, 10:32am

codeformer face restoration with chaiNNer , white balance with levels, channel mixer and color balance with GIMP:

okieman · June 19, 2023, 1:08pm

Wow, that came out very good. I’m impressed! I’m going to Google those items you mentioned!

okieman · June 19, 2023, 1:12pm

Plus, I already have accounts on Github and HuggingFace.

s7habo · June 19, 2023, 1:24pm

I will highly recommend the chaiNNer This is free software node based image processing tool with which you can use especially many open AI algorithms to refine the photos:

With it I used the face restoration. Everything else I did with GIMP.

okieman · June 19, 2023, 1:30pm

Boris, Done! I’ve downloaded that, plus added four related links so I can read up on these innovations. It’s very exciting.

s7habo · June 19, 2023, 1:38pm

What I did with GIMP:

White balance with levels. I assumed the man on the bottom right has the gray shirt.:

Then I used Channel Mixer to “reconstruct” the missing green:

Then I played a bit with color balance:

Then lightened the photo with curves:

And desaturated the red with Hue-Saturation:

okieman · June 19, 2023, 2:34pm

Of those four, the one I have not used is the Channel Mixer.
It can do something I was not aware of, going on what you have shown me here!

david · June 19, 2023, 3:06pm

I have a GIMP plug-in, col-cast-reduction.py. This is the result without any further adjustment.

The plug-in, should you wish to try it. It is a one-click operation.

col-cast-reduction.zip (2.6 KB)

Entropy512 · June 19, 2023, 4:54pm

Wow, had never heard of this before.

@s7habo already posted the link in a reply - thanks! That looks REALLY useful, especially (potentially) for a bunch of old negatives I need to digitize and restore.