I'm a big believer in working backwards: starting from the desired end result and then choosing the equipment that's suitable for it.
The photos that I'm most interested in generally have specific needs as they travel from being a digital file to a finished electronic image or print. Some need to be in black and white while others require colour; some have to be in a square crop while others are long skinny rectangles. Some photos require an immediate impact that can own a room, while others are best served by the more intimate and interactive experience of a hand-held print.
Of course, many photos aren't so temperamental. At that point it's a personal choice for what suits the purpose and vision the best. Projects naturally evolve and change, and the tools can be part of that. My ongoing 'time and motion' series started with my smallest film camera, the Olympus XA, moved on to a medium-format Fuji 645, and will probably involve my Hasselblad 6x6 next. And while I've picked an aspect ratio for them – 1:1.618 – I'm still not sure what size will be best for the prints, although I suspect it will be large.
Higher resolution digital and larger film formats can produce larger prints, and newer digital cameras generally provide better image quality than older ones. But that doesn't always matter, and there are times when I will choose the more limited tool specifically for the way it will impose itself on the process and results.
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