Originally posted by braver Now since the DNG has an embedded JPEG preview, this is what may be happening here. Must experiment with PEF vs DNG to see if it makes the lag go away.
I very much doubt that the embedded jpeg is corrected (but I could be proved wrong), PEF files have always also contained an embedded jpeg.
Originally posted by braver Regardless, I'm curious how the correction actually works. If it's not applied to PEF, i.e. to the raw-est data, then it will be lost if I rerun Adobe DNG converter on the DNG, which I do in my workflow to make sure I get Adobe-approved DNG, with some corrections applied always (per "The DAM Book").
Basically if the lens ID, FL, aperture and the approximate focus distance is known then the degree of compensation required to counter vignetting, CA and distortion can be applied based on tables generated by empirical testing of a set of reference lenses. Unless the DNG converter strips this basic EXIF data then any converter with the appropriate smarts should be able to compensate for the three main aberrations, but currently I think it's only the Pentax DCU4 lab converter and possibly DXO that does?