I'm pretty new to photography and I recently bought a D90 (about a month ago) along with the kits lens (18-105mm VR) and a cheap 70-300mm. I've been contemplating on buying a prime lens that has a wide aperture which I can use in low light situations as well as in the movie mode of the D90 to get good depth of field. I kinda like the range of the 35mm because, as I am using a DX format camera, it is equvalent roughly to a 50mm, which is normal. However, thinking ahead, I cannot use it in case I decide to upgrade to an FX format camera. The 50mm, on the other hand, is a full-frame compatible lens, but the DX crop makes the view a bit too 'far' for my taste. Any advice? I've read that both are sharp lenses. Any opinion on this as well? Btw, my budget is only around $200 so these are, I think, my only choices.