Out of the Nikkor T, are they any lightweight and affordable lenses (around two pounds 1Kg) in the 900 - 1000 - 1200 range (I have 600)? The process lenses like the Ronars in that size are usually made for ultra large format and are therefore huge. Or maybe a convertible? I reckon that a lens that long is not the most commonly used, but could be worth too shoot on a larger chrome what would otherwise be shot on rollfilm. Now, don't ask me how I would extend my camera to that length! I still have to think about it ;-)