Hello everyone. I'm currently using a d300 with a 12-24mm f4 to shoot mostly architecture - I need to go wider than 18mm (35mm equiv on DX) for indoor shots and was thinking on upgrading to the d700. The question isn't whether to upgrade, its what lens do I use? The obvious answer is the 14-24mm f2.8 - but its sort of out of my price range if I were to buy the d700 and this lens together. I already own the following lenses: Nikon 15mm f3.5 AIS Nikon 16mm f2.8 AIS fisheye Nikon 20mm f2.8 AFD Nikon 28mm f3.5 pc Nikon DX 12-24mm f4 Most of these lenses work great on the d300 - except the widest one, the 15mm 3.5 - for some reason its not quite as sharp as the 12-24mm - I'm not sure if this is due to coupling it with a DX sensor or what, but 100% crops don't really compete with the 12-24 - I'm wondering if anyone has any experience using this lens on a full frame digital camera such as the d700, d3, d3x and what are your results? Do you think I can manage full frame with the assortment of lenses I have already? or should I really consider the 14-24 sooner than later? Also, any other recommendations are welcome. Thanks!