I scan old original photos from the 30’s and 40’s and for some of them I get some blueish metallic reflections that are not visible “in person” (and the photo paper is not glossy). I think this phenomenon is called silvering (or mirroring?).
Here is an example with one of my photos (look on the person and in the dark areas of the photo you’ll see the blueish reflection – look at the photo at 100% size otherwise it can be hard to see):
I use a color deconvolution plug-in in Photoshop to remove these reflections with amazing success:
But the reparation process changes color tone of the image (the sepia). In the example above the original is a bit more brown/yellow.
How, with Photoshop, can I restore the original color tone after removing the reflections?
Your filtering has changed brightness and contrast and inserted a new color here and there. That’s already said by others, too.
My suggestion: Fix the blueish areas selectively by placing a masked color overlay.
At first make a duplicate of the original image. Keep the original in the bottom as a spare. Hopefully it’s not needed. Insert a 60% gray layer below the duplicate. Let the duplicate have Blending Mode = Color. Blueish areas and sepia areas can be seen clearly. Use Select > Color Range > 50% Fuzziness to make a fuzzy selection of the blueish areas:
Do not lose the made selection! Save the selection if you suspect your carefulness.
Pick the sepia color to the foreground color with the color picker. Write its RGB values to paper in case you want to use it later elsewhere.
Change the blending mode of the duplicate back to normal Insert a new empty layer above the duplicate. Let it have blending mode = Overlay. Insert a layer mask. It will be = the blueish areas if you succeeded to avoid losing the selection. NOTE: The mask is not strict BW, there are greyshades because it was a fuzzy selection.
Remove the selection (it probably vanished when the mask was created and that’s OK). Fill the new top layer with the sepia color:
That’s the new version with fixed blueish areas. Test it by closing the top layer temporarily.
If you want to recolorize the filtered version, desaturate it and place it under the sepia overlay. It’s tried in the next image. NOTE: The layer mask is disabled. It’s not needed:
Overlay blending is only approximately right. I do not recommend to use it as unmasked to desaturated original. use it only where the color is lost.
Actually It’s not lost. It obeys too well exposure strength borders. I guess the sepia treatment is done incompletely – too short whitening bath, there’s still much metallic silver left in thick areas.
If it really is blueish (=not a white imbalance as an opposite of brown) it can even have got a second toning which converts a part of the silver leftover to another colored material. A darkroom specialist can tell the truth. Unfortunately I’m not one.
The original sepia toning changed metallic silver to brownish silver sulphide. Other tonings: Gold as in place of photo paper silver is blueish black, not yellow. At least selenium has been used to replace the silver, too.
All these tonings have artististic impact but also they slow down the degradation of the photos because metallic silver is very fragile in non-pure air.
Source : Link , Question Author : AlexV , Answer Author : user287001