The original image as presented for feedback.
Our Anonymous Photographer has a good sense of composition, placing the subject in the bottom left corner and allowing the viewer to follow the same gaze and direction as the subject who is drawing or sketching the scene. This is well done, but there's just one problem: we can hardly see the subject. Tonally, the subject is too similar to the surrounding rocks and while the blue shirt is helping, the colour of the hat and trousers merge perfectly.
Perhaps that's the whole idea behind the photograph - this camoflagued person, but I'm going to guess we should look at him a little more easily.
Given the exposure on the person is pretty right to start with, I won't lighten him. Instead, I will darken all the tones surrounding him which will produce a similar effect:
Now the blue stands out much more strongly, so let's work with this and increase the saturation in the shirt so it is stronger still:
I think this is much stronger. Looking at the tonality of your subject in comparision to the surroundings and making adjustments is one way post-production can enhance what is essentially a very good photograph.
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