I kicked iPhoto to the figurative curb once I realized how badly it manages files. Import a JPEG/JFIF image into iPhoto and watch the Original and Modified directory trees. iPhoto re-encodes the file if:
o The imported file has a color profile embedded
o You rotate the image
o It damn well pleases
It appears to do so with a fairly high quality factor, so the Modified copy is larger than the Original. Attempts to "revert to Original" often silently are ignored, and if one deletes the Modified copies, iPhoto silently replaces them. There's really no excuse for this -- it degrades image quality, complicates file management, and burns disk space needlessly. This is not a condemnation of iPhoto wrt features -- there's no excuse whatsoever for re-encoding an image that can be losslessly rotated.
By perspective control, are you talking about stuff like keystone transformation on buildings shot up close? That's outside of either application's charter, of course.
I read that Aperture leaves the files alone and properly stores changes as metadata, so I tried it first. Couldn't figure out the flow. I tried Lightroom, and it was quickly clear to me how the app works, so that's what I use now.
I'm ignorant of the behind the scenes manipulations in these programs. I pays my money and hope it works (and free is even better). Isn't the latest iPhoto version lossless with both jpeg and raw?
Any ideas of a lossless workflow would be appreciated.
Yes, I meant keystone effects, general leaning building and skewed squares. These seem like very common problems that all of us deal with, or don't. I use the skew control in Elements and PTLens (which also deals with lens distortion). I just hate to drag photos from one program to another and back, importing, exporting, turning from raw to jpeg, etc. and generally being a pain.