Hello to you!
Great frigures! To answer your question, there is no rules for ammount of detail in any allotted time. you are simply puting in as much can or as little as you want in any given ammount of time. I love your bold and chunky style with the charcoal, for your full figure draings, but the tightness and delicacy that your rendered the hands in show that you have finness and can draw cleanly. I would love to see more of that in your figure drawings. for your next long pose like 50min, maybe you can render the figure the same way as your hands. using careful observation and those beautiful lines of yours. If you are running out of time, and the drawing isn't where you want it, don't worry about it. You are practicing your rendering skills and you will get faster. if you find that you want to have a more finished drawing, then for your next practice, don't give yourself a time limit. Just draw until you feel it is finished. But do time yourself. That will give you some idea of how fast you work. Have fun!!!!!
Ron
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