your halftones are too dark and some of your highlights are too bright and isolated. Take your average light mixture and try cleaning up some of it.Your basic structure is good you just got too far away from the average light.

overall, this is good. The lesson is suppose to really be about edges mostly. Your edges are too hard on the left side where light goes into shadow. Try softening more edges. Look for the one or two HARD edges and let the others all be softer.

it's better but like you said, the edges are way too hard.

Great job! You really got the point of the lesson

Wow! Great job!

I took your painting and brought it along a little further by addressing small little edges that were still not softened enough, and therefore creating little sour notes that stood out. Overall, you were getting your edges pretty good. But when you don’t address all of them, the ones that are still a little too sharp or picky or look like lines will stand out. Try to go around with a fine tooth comb and knock out every little edge that needs to be soft or hard. I also cleaned up your half tones a little bit do a deep comparison between your image and what I did to it to learn more.

I think it’s more like him than you think. This is a great set up. Now let’s work those edges

there are some good things happening here but the lesson on this head should be about edges most. Your edges on the shadow side need more soft and firm and less hard. avoid making his wrinkles look like lines. think about combining wrinkles into larger planes.

Your drawing is a little off on shadow side. Try taking your reference and putting it right next to the painting and with rapid eye movement look back-and-forth back-and-forth at that side of the face and see if you see what I see.

in the final photo I can see that your halftone is too dark in many places, like between brow.The middle shot is actually better

don't lose the overall average light of his skin color and value. You may lose control of it all if you are not careful. Let's see what you do with edges now.

that's good! I would suggest you use a little smaller brush and make it force you to be more specific about the smaller shapes that make up the bigger shapes.

I like how you simplified his head. Good job! the edges are not complete though. look along his cheek and down to chin , and brow where it meets shadow, all need to be softer.