GIMP Tutorial

[denzjos]

@Ofnuts, thanks for the tip. Tried it out with layers 'DD' for shadow recovery and it needed some color correction. I used the 'L' and the 'MMM' to solve this.
I also tried the 'Colour / Hue-Chroma' filter and get about the same result with less effort. It depends the correction needed on a photo, sometimes one have to use a combination from filters / masks and layers. It's not always easy to have a perfect result, but it's better to have it approximately right than completely wrong. And everyone have a personal taste about this.  

   

[Ofnuts]

(09-11-2023, 09:26 AM)denzjos Wrote: @Ofnuts, thanks for the tip. Tried it out with layers 'DD' for shadow recovery and it needed some color correction. I used the 'L' and the 'MMM' to solve this.
I also tried the 'Colour / Hue-Chroma' filter and get about the same result with less effort. It depends the correction needed on a photo, sometimes one have to use a combination from filters / masks and layers. It's not always easy to have a perfect result, but it's better to have it approximately right than completely wrong. And everyone have a personal taste about this.  

The global problems with shadows in 8-bit images (ie, JPEG) is that you have not that much data to work with, and when you increase the values you increase differences and incur banding and color shifts. So you should avoid the general controls (Levels, Brightness-Contrast) and use the more color-safe tools Exposure or Hue-Chroma (using the Lightness slider).

[denzjos]

Another workflow to lighten up a photo :
Make a copy from the original layer
On the copied layer :
Filters / Blur / Gaussian Blur (used here value 20 - if not satisfied, try different values)
Colours / Invert
Colours / Desaturate / Desaturate
Layer mode 'Overlay'
To lighten the photo more, make a duplicate from the desaturated layer