I'm completely new to graphic work! I am looking to achieve the same grey shade effect on these images using GIMP.
Looking at your pictures, it see that the desaturation mostly happens on the light tones, so try something like this:
- Duplicate the layer
Layer>Mask>Add layer maskand initialize to
Grayscale copy of layer
- On the Mask, use Brightness/Contrast to increase both lightness (a bit) and contrast (some more)
- On the Layer, use Levels to reduce the output level of the whites.
Your layer stack will look like this:
And the result is: