dhama -
i think what you are after would be things like the open competitions over at CG talk, or the book submissions competitions by Ballistic.
because of its very nature the challenge cant really be used as a personal measure: the theme may not be ones own field, the restrictions may not fit ones own working methods.i use the gallery to chart my progress - and to obtain non-bias feedback,
challenges of old always were about the WIPS (its in the guidelines, encouraging you to post them).
but then since i've joined the names have changed quite a bit - maybe it is seen in a different light now.

Experience is no substitute for blind faith.

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