At least as far as the 300mm aspect you commented on. Yes, you can get 300mm using the D70 (I know, I have one, use it with my Tamron 70-210mm), but it won't get you the same effect as the traditional look of a 300 f2.8 on a full frame chip, I know, I tried that too. The problem with the DX format is that in order to frame an image the same on a DX camera as on a FF camera, you have to use a shorter lens, hence less depth of field (assuming the same f-stop). Picture this: if you are a certain distance from a model, and you get a nice tight 3/4 shot using a FF camera and 300mm lens, in order to frame the shot the same way on a DX camera (like a D70) you have to either put a 200mm lens on the camera, or use a 300mm from 50% farther away from her, right? The first solution will increase your depth of field, the second will also, but it will change the perspective (its all right there in that article). The biggest complaint I hear from DX shooters is the too-sharp backgrounds, all things being equal. For many, many years, fashion photographers (forget the sports guys who need all the mm they can get) have used the 300mm wide open because of the specific effect it gives both in terms of compression and shallow depth of field. This is one reason why I am giving up on the Nikons after so many years (and BTW, I bought a D2X, and it is an EXCELLENT camera). Here's an example of a true 300mmm lens, although I think it was shot at f4. You could accomplish something like this on a DX camera (Andy McFarland does it all the time) but only if the background is WAY far away. And yes, the 300mm IS a big (and expensive) lens, which is why I'm thinking of trying something else, which if it works, I will post a message.
Andy Pearlman Studio