Matthew Brennan , Aug 10, 2009; 07:31 a.m.
You ask a lot of technical questions of current bodies, most of which I'd care to answer by saying unless you are going to expect truly massive prints from your camera then pixel count, pixel size, sensor size and type and resolvable detail from avail. lenses are mostly moot points. I have some great Nikkor glass but unless I can keep the whole camera/ lens combo absolutely still whilst the mirror/shutter actuates then the resolution of either the lens or sensor is limited by the support offered. Of course a medium format sized sensor will yield more detail, given it's used properly but at what cost & as a means to what end?
Current technology dictates that too many pixels on a given sensor spoils the broth via noise etc. Until the technology improves where by resolution gain is improved without exposure penalties we are left with the current Nikon 12 MP FX and DX CMOS sensors which provides arguably the best results with the least penalties. At least this is my line of thinking and I voted with my bucks and purchased the D700.
By mounting FX format lenses on DX format bodies one can eliminate any soft edges / vignetting that the lens might otherwise exhibit on an FX format body. In other words, only the light from the centre of an FX lens illuminates the smaller DX sensors thus using the 'sweet spot' and not projecting light from the outer limits of the lens. Typically (but not always) a lens will have best sharpness in it's centre and will suffer sharpness and light fall off etc around the outer proportions of the lens. I used several FX based lenses on the D200 & D300 and found this to be so.
If you are wanting to purchase a 300mm / 400mm lens or longer and you already have a DX body on which to get the DX crop factor gain then perhaps the D700 body is the one for you. I have no need to make a print any larger than 14 -18 inches long and my current set up will do that for me to my desired standard, I'm sweating over what may or may not be around the corner.
Although I have shifted to the Nikon FX format I'm a firm believer that Nikon intends to maintain it's DX format in both D-SLR bodies and DX lenses well into the future. I'm also of the opinion that why should you wait for the next model if your opportunity cost is missing out on current photographic opportunities ........ Grasp your photographic opportunites now! Buy a currently avail. body or better still invest in a lens which is far more likely to stay with you longer than a camera body will.