Dear Friends, Sigma has a fairly new lens out, a 70-200mm f2.0 made for digital cameras. I simply cannot afford a Nikkor of similar values. So, here is the situation and a request for your advice. Please note, in years past I used fairly nice rangefinder cameras and even the SLR concept of digital is new to me. (I must say, the sound of the shutter click of a digital SLR is refreshing, even if the rangefinder was quieter.) Considering the Sigma lens, does anyone have advice on this particular lens? Most importantly, in choosing a telephoto for nature images which I love, some advice is dearly needed. Most of my shooting is from perhaps 30ft to 100 ft (9m 31m), from experience. I am looking for a lens to bring me closer. The 200mm lens is close to about 300mm in 35mm format; this tells me the magnification factor is about 6x. This is magnification as in a binocular and not the zoom factor. From this I beleive visually through the lens to get about 5ft to 17ft of the image object? (1.5m -5m) If so, 200mm(with digital factor of 1.5x) is ideal for me. I have not used a telephoto lens before. I need something decent and affordable and at the same time not too, too bulky. Any advice will be greatly appreciated. Any thoughts on telephoto will be appreciated. Thanks for ANY input. TomDart.