Restore image with negative colors

Question

I have an image that was taken using a negative color filter long ago, but now I need the normal picture, is there a way to get a good quality of that picture with the actual colors? The current software I am using is GIMP.

Answer 1

We may be talking about a scanned color negative film stock widely used way before the invention of digital cameras.

These images had a yellow and a red mask for color absorption. Hence negatives had an orange rather than a white tint:

^{Image source: Wikipedia cc}

To obtain a positve color image from these sources we have to

1. Remove the orange mask

   • Colors > Pick white point: choose an area outside the image

   

2. Invert the colors

   • Colors > Invert

   

3. Adjust colors (many negatives will have a heavy blue tint):

   • Colors > Pick gray point: choose a gray area from the image

   

Note: removing the orange mask will unfortunately lead to a reduced pixel information as compared to color scans.

Answer 2

GIMP has an invert command you can apply to RGB and Grayscale images:

to

You can acces it through Colors → Invert.