What's funny about all this is that the art directors I know (NYC market, I have worked with ADs spanning the gamut from bergdorf goodman to macys) - and in my experience none of them know anything about cameras much at all. They do not ask about how many megapixels, bit depth, file size, or such. If anything, they think all digital is kind of lame compared to film, but that is changing fast. I have gotten comments like "wow, that's a nice lens! - it was the Canon 70-200 2.8. and I was shooting for a HUGE project for a residential building in Dubai - the tallest building in the world apparently; but for the most part, they do not notice or care about the camera at all. MF - fine. 35 - fine. They do not notice. Their relationship is with the MONITOR, not my camera. I asked an art director last week who is a friend (she has shot large campaigns for Victoria's Secret with Russell James, Patrick Demarchelier, bla bla bla, and she replied that she doesn't know a thing about it and does not care. She assumes that whatever camera they have brought is good enough for the job. What she looks at is the LIGHTING AND COMPOSITION ON THE MONITOR. Now these photographers I mentioned shoot on all kinds of cameras (Phase, Canons, etc.) and it looks like the camera choice is a non-issue for everyone but the photographer on these shoots with some of the largest budgets and biggest models in the world.
Are any of these guys getting fired for lack of micro contrast? Did the art director get scolded for letting a toy camera onto the set? Did inez and vinoodh's images at the fashion photo exhibit I went to look inferior to the other images because they shoot with Canons? Er, no.
Did Paolo Roversi's images look like magic in his show last fall? Yup. It's the lighting, the technique, the medium (film), the printing, models, etc., etc.
As far as I can tell the differences between these cameras we are discussing in this thread are just about microscopic compared to some of the bigger issues such as lighting and technique. And for the most part, anyone who is not the photographer or the retoucher has no clue about it. So while some can spot differences between these cameras (I can sometimes...) which have chips which are not very different in size (35mm vs. CROPPED 645) it can be said for sure that in many instances and for many photographers, the purchase of a cheaper, smaller, lighter camera which performs at 90% of the quality of the cropped 645 camera is a good idea. The extra $15,000 could then be spent on better models, locations, retouching, portfolios, plane tickets. $15,000 extra - thats a lot of trips.
I have personally shot MF and 35 for years, and I may buy one of these new Mamiya DL28 kits next week. But I am not going to kid myself that any of my clients are going to notice ;-)