artman, please pass on this ссылочке
http://forum.artinvestment.ru/showthread.php?t=1715. Here is written that should inform about a picture that forum members have tried to answer your question.
Please photos - large and clear - the persons and trafficking in the picture. If the face and the back is an inscription, signature and generally anything other than painting - it all apart and take a photo of the large, please.