John,
I also have a 50mm f4 flektogon P6 mount lens on a tilt adapter that I used with both canon and sony SLRs. I am interested in landscape use and in avoiding focus blending. The tilt adapter works but it is much easier to use with live view than without. I got the canon because I was also interested in flat, sometimes called orthographic, stitching where you mount the lens on the tripod and slide the camera while the lens remains steady. That removes the possibility of parallax and is an inherently more accurate technique.
In the end I think I'm just going to do rotational stitching with focus blending since my probable next camera, the Sigma SD1, is unlikely to have live view.
I'm not sure how well the canon would work for architecture but it certainly looks good on the Nex-5 with full shift in both directions. I'm pretty sure it would also make an excellent architectural lens on the sony but the lens will have to be modified because the register is too short for Sony SLR use as is.
There is an extensive documentation of conversion of the lens in the "photography on the net" forums.
Mike
How did you decide on the shift lens that you bought and what do you want to use if for? I ask on account of those who say that post processing is good enough. I ask because shift lenses look so beautiful in terms of there mechanics and would love to buy one for architecture, but have not yet taken the plunge! And I have this fl fd canon adapter sitting around wanting to be useful.
