Critiques are welcomes

Hi there,
i'm Azhash, 25yo, nd im studying drawing techniques :Loomis, Bridgman, vandruff, vilppu, hoghart, gnomon, prokopenko, nd from various references

I love to learn more and more every day, so don't hesitate, i would know what's bad, my weaknesses, and what should i study more. (gesture?, structure?, anatomy? perspective? line "quality"?) U will not see a lot of shadows on my sketches, i'm bad with shadows and colours, so right now i'm studying structure and perspective to understand why a shadow do smthing or somehting else.

My draws: http://azhashsketches.tumblr.com/
Thanks for any reply

Wow Azhash, these are really great. I love your style. Sorry, I don't have anything constructive to say; just keep up the good work!

Hi Axhash! Your gestures look so wonderful! It shows you have a lot of understanding behind your loose sketches. Your strokes feel definitive, confident, and fluid! I'd love to see you develop on them, and maybe make a more polished piece based on some of these.

There's a website called posemaniacs that has a tool with 3D models to draw from. The page that specifically is labeled "Hand Viewer" has the models in strictly grayscale, that acts as though there's a light shining directly from the viewer's eye, or just straight ahead. So the "closer" the object is to the screen the brighter it is. http://www.posemaniacs.com/tools/handviewer/ It might give you some simple perspective on shadow's workings. there are plenty of free resources on the subject online. Here's one small example, but it might give you a good starting point to experiment with.
http://www.deviantart.com/art/Shading-Tutorial-A-98851485

Thanks for the replies, i really appreciate.

Yes i know posemaniacs, i've been working on the figure drawing tool for tons of hours, it's really a great way to understand foreshortenings for me. The hand viewer tool is great too, it's kind of weird to have the light comming from behind the viewer as u said because it will make me draw shadows that are so close to something like contour lines. But with this issue in mind, i just realised that contour lines doesn't really exist in real life, so being able to draw from this tool can be a great challenge. I'll have this in mind.

Thank for the link, yes it was a good starting point, just after read it i found this serie of videos on Youtube, it's long to watch all the light and shadow playlist, but if u want to learn the basics like me, u'll enjoy it :
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