Life Drawing Picture

I have life drawings of my dad, four were done with just pencil, and the last four were pencil and pen.

25 mins - Most parts of the body are to proportion, only the face lets it down.
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10 mins - The neck is to long but he was looking up and the belly button is too high.

10 mins - I think this drawing went well considering it's only a ten minute drawing, good proportion as well.

15 mins - The arm is too thin and bendy and the shoulder looks a bit square.

Pen and Pencil Used for the next Four.
1 hour , 50 mins - This took a long time to complete and still the hand and hair on the arm are out of shape.

2 hours , 30 mins - Very difficult, this one annoyed me the most because of the crossing of the arms but it's almost exactly right. The only part I felt I needed to change was to put an outline on his back.

5o mins - Again this was a hard one but there was less muscles and hair to draw. Although the hair on his head was a real problem, The ink I used was to light in some areas despite that fact his hair reflects light.

1 hour , 30 mins - The hair is off shape and the lower half of the head miss proportioned i think, also the angles with in the arm look slightly off. Then again this was the last drawing i did and i was quite tired.