True white in old black and white photos

[barth90]

I’m using Gimp 2.10 to  colorize old photos. I have no problem with differents hues. My question is about true white. For example, I have a photo whith snow. On the original, the snow is greyish. If I select white from the palette and using a brush to color the snow, it remains grey. Is it possible to have true white?

Thank you

[Ofnuts]

(02-09-2021, 11:22 PM)barth90 Wrote: I’m using Gimp 2.10 to  colorize old photos. I have no problem with differents hues. My question is about true white. For example, I have a photo whith snow. On the original, the snow is greyish. If I select white from the palette and using a brush to color the snow, it remains grey. Is it possible to have true white?

Thank you

It is possible to have pixels with value (255,255,255) (or 1.0, 1.0, 1.0).  How there are displayed is a matter of color profile (if there is one and color management is enabled), graphics card and driver, and monitor. So do you see whiter things on the screen outside of the image display? Is the "white" in the palette really true white? Is the brush fully opaque?

[rich2005]

(02-09-2021, 11:22 PM)barth90 Wrote: I’m using Gimp 2.10 to  colorize old photos. I have no problem with differents hues. My question is about true white. For example, I have a photo whith snow. On the original, the snow is greyish. If I select white from the palette and using a brush to color the snow, it remains grey. Is it possible to have true white?

Do you want a true white ? Rarely get snow where I live but looking out the window, the snow is white and grey and full of shadows to give it shape.

My suggestion, a bit of pre-processing of the greyscale photo. (In RGB mode) prior to colourizing.
Use a luminosity mask and "tweak" the light areas. This using a LL setting as a selection, adjusted by the color-curves tool.
I do not have a suitable snow scene so a comparison of the BG of this will have to do. 

   

You can get a luminosity mask plugin from http://sourceforge.net/projects/gimp-too...s/scripts/  download the zip, unzip, read the documentation.

edit: Totally off topic, but amusing - this from the local newspaper
Two arrested after suspected intruders struggled to hide their footprints in the snow

[barth90]

Thank you. These are good tips. I will explore those avenues