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Presenting Photo Opportunities by Corinne Vionnet
Jörg Colberg's profile photobonifacio barrio hijosa's profile photo
Well, there is no copyright on a method, and I find it too narrow to say that nobody else can do it. I think conceptually, Vionnet's work is more coherent, and it makes more sense than Khan's. Khan has one or two great photos, but the rest are really just a stretch. Vionnet found the perfect subject for this work. And just as an aside Khan wasn't the first one to do these, either. He just got a lot of press.
I don't think it is based on taste. A lot of Khan's work feels like a stretch. You also might want to look at Jason Salavon's work who has been stacking images for a long time.
Krzysztof Pruszkowski "Fotosynteza" in the analogic era and with his own photos
I saw first in Madrid, a collective exhibition of a project called "Imagina": p.8 (in spanish)
they made a big heavy book

another one recently experimenting this kind of technique, is a Japanese I just can't remember, made single images mixing hundreds of portraits