Originally posted by Bultkrans DNG conversion is a compromise.
I don't think I'd call it a compromise. I don't think you loose anything using DNG. Except perhaps Makers Notes info about the lens used for the shot.
DCU, SilkyPix Pro 4 and the PhotoMe EXIF viewer are the only packages I have on my PC that can read the Maker Notes in a PEF.
My freeware browser/limited packages (XNView, FastStone) can read and convert PEF, using their DCRAW component, but they don't allow any raw-level adjustment, so I never use them for that purpose. They can't read Maker Notes correctly and XnView (don't know about FastStone) does not interpret the K20D's total shots taken count correctly. (I can get that easily enough from PhotoMe.)
PaintshopPro X can't handle K20D PEF, but it's using a non-configurable raw converter, so I prefer to convert in SP Pro first. So I don't worry about setting DNG in the K20D just to suit PSP X.
DNG in the K20D does have a weakness: it's bigger than PEF because it uses no lossless compression. This is no longer the case in the K-5 & K-7.
The only time I've needed to use DNG, I actually did so after the shot. I was using the PhotoAcute software which can't handle PEF. PhotoAcute seamlessly invoked the free version of Adobe ACR, which it first asked me to download and install, to convert the PEF to DNG before proceeding, so all I really lost was some time.
I think the Mac version of SP Pro 4 must be stable, because the host of
www.silkypixforum.com is a Mac user. Why don't you ask there.
Dan.