|*Hello from Sid and the Critique Club*
Congratulations for your high placing with this most appropriate image for the challenge.
Is this a self portrait Marcel? If so, you are a multi talented man, well done. This is an excellent image, your chosen aperture is creating a nice centre of focus on the playing hand, the composition is very good with a nice diagonal running through the image. I know you do concern yourself with composition and have asked for help in the past, have no fear, you most definitely got it right here Marcel, it works perfectly.
I like the lighting and the mono processing it works very well here. There is an argument for making the chords hand the centre of focus which I think would also work very well, but the argument is equally strong to do as you have done as this is the hand from which the sound emanates. The few minor blemishes on the front of the guitar would benefit from some processing attention but its certainly not a major issue.
Well done Marcel, this is an excellent entry in every respect, Sid