Ever since I started out with 3D lots of years ago I have always wanted to try to create a human portrait and this is my first try at it.
Created with Blender 2.69 and rendered with Cycles.
I hope you will enjoy it!
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paolo
Hair and basemesh look really good, skin shader is mostly good too, with a few adjustments to geometry and skin shader this could be a REALLY GOOD piece. I’d like her to look more femine, in order to archieve that skin should be smoother and face should have softer curves! I really think you should play a bit more with girls anatomy to make her look more appealing and femine!
Heres just a fast photoshop showing what I would change to make her look more appealing to me 
Anyway this is really good for a first go at it! Have tried it myself and ITS HARD.
damn fine image, only issue is the bit under the bottom lip to the chin is a bit flat, otherwise, well done!
Where can I get that studio backdrop? That makes for a great lit scene I think. Also great job on the render!!
I would have never noticed that until you said something… But your right, a little dimple under the chin would look better I think.
Thank you for the feedback! You are right about the skin and the face not being softly curved, specially the chins. I realised after having finished the detail sculpting that some parts of the sculpt had flat spots, but since going back some levels on the multires modifier to resculpt things tend to mess up the overlying levels I didn’t try much to fix it. I also think now that the skin shader should have sligtly less/shorter SSS because of the inside of the nostrils that have darker shadows and I should maybe have used the texture blur and less bump on the spec to give the skin a more femine look. But you can’t do everything right the first time! 
The sculpt is actually made using reference photos of one single person (does someone recognize her?) to get the proportions right, but I can say, they are not too similar to each other.
Thank you! The backdrop is a picture of a concrete wall from CGTextures.com ( ConcreteBare0145) added in the composition stage with decreased contrast and colored gray-green to lock similar to the backdrops professional photographers uses.
Small Troll: Thaks! You are right about the flatness under the lip!