[gchpaco]

Oh, no question that you have a better MTF from an Alpa than you would from an 8x10 at f32 (a perfectly reasonable working aperture for 8x10). I think the 8x10 can still out resolve the Alpa but you're getting into that ugly 20% part of the MTF curves. The rule of thumb I've had for a while is that digital has fewer, better pixels; the digital back hits a wall beyond which you cannot proceed any further, but at and up until that wall the results are superb. I think the current sweet spot is speculated to be 6 cm x 9 cm cameras, mostly because of diffraction and film flatness issues. And reversal film has notoriously poor dynamic range, and mediocre color correction; that's one of the things that pushed me to doing all negatives in my photography.

A professional is probably only going to use film these days if they want a specific effect; say, infrared, or sometimes people fart around with Holgas and call it art. For an amateur, the $20,000 digital back that can compare with a 4x5 with some decent lenses costing a tenth that much is a much harder sell. And that's pretty much where I sit; I'm not going to spend $50,000 on a top of the line MF outfit. I might spend the $1.2K for an X-100, though, still mulling that over. A couple thousand buys a lot of film and developer.