The interesting thing about possibly converting to a DSLR is that prime lens focal lengths are all based around the 35mm frame size. This means that one has to take the current line of prime lenses and adapt them to your needs in the DSLR world.

Part of the draw of switching to a DSLR is I would be able to use my 50mm 1.8 as a short portrait lens (75mm). I prefer the 105 mm focal length for a lot of my work though. The problem is, in order to get a 105mm lens equivalent in a DSLR, you would have to buy a 70mm lens in the 35mm format. They don't exist. The existing lenses with fast maximum aperatures are the 50mm 1.8 and the 85mm 1.8 (the 1.4's are out of the question.) The 50 turns into a 75 (kinda short) and the 85 turns into a 128 (kinda long) so there's no lens sitting in the sweet spot of that 100mm area. The 60mm lens would turn into a 90mm, which is an acceptable focal length. But the maximum aperature I've seen on a 60mm lens is 2.8.

So, what do you guys do? Do you find that a 50mm lens (75mm equiv) is sufficient for portraiture?

Thanks,
Rick