I've been experimenting with the Alpa corrector today and didn't notice any softening (but I am on a Retina display so that's equivalent to about a 227dpi print which can hide a touch of softness).
However, I have realised that there's nothing to be done for tilt.... I took this shot this morning with 0.7 degree tilt and here's a version slightly tweaked in LR but the crop that follows is from the original and shows the sort of distortion that it would be nice to be able to correct. I am not sure whether, with tilted shots (possibly tilted and shifted) one should apply as much as the software allows (i.e. with the correct parameters for lens and shift etc. I am also unsure as to how best to use the correction profiles with Sinf and S33 at the end of their filenames. At which subject distance should one switch from Sinf to S33 and can I assume that the short barrel versions of the lens mounted on Alpa shift adaptor use the same profiles. As usual with Alpa, the documentation is rather brief, and written in Swinglish.... on the other hand, I am finding it quite easy to get my movements and focus right. This one has focus everywhere.
