Mac OS X 10.4.3, an incrememental update to the latest version of the operating system for Apple computers, adds OS-level support for RAW files from newer digital SLR models including, in our testing, the Canon EOS 5D and Nikon D2X (and probably a number of other 2005-vintage digital SLR RAW files which were previously not recognized).
OS level support for these files includes the display of OS-generated thumbnails in the Column view of Finder windows as well as being able to convert them in iPhoto 5.0.4 and Preview 3.0.3. Though we haven't located on Apple's web site an up-to-date list of camera RAW files supported as of OS X 10.4.3 (an outdated list is here), that list almost certainly includes all of Aperture's preferred models (see the sidebar on this page).
We've also compared about two dozen RAW photos processed to 16-bit TIFFs using Preview in OS X 10.4.2 and then again in OS X 10.4.3. The photos were taken with a trio of cameras: Canon EOS-1D Mark II, EOS-1Ds Mark II and Nikon D70. In all cases there is a noticeable improvement in the conversion quality in OS X 10.4.3, with obvious differences in noise levels, artifact suppression, image crispness and overall tonality. Except for differences induced by the tonal change, however, colour rendering appears to be about the same. For this set of pictures, it means that the Canon Mark II files processed through Preview in OS X 10.4.3 look reasonably good overall, while the D70 files fall short. Our experience is fairly consistent with the 10+ photographers who've emailed us their OS X 10.4.3 conversion stories since yesterday (the Mac OS update came available on October 31, 2005).
We have no plans to make Preview our primary RAW converter of course. We ran this mini conversion quality test to try and get a taste of what Aperture's RAW conversions will be like, since each application will utilize the same OS-level code for some or all of the RAW processing. Whether Preview conversions will exactly match Aperture's conversions we can't say, and ultimately it's the as-yet-unreleased Aperture where we need to run these tests from. Looking at the combo of Preview and OS X 10.4.3, though, we remain cautiously optimistic about the conversion quality Aperture is going to offer.