This has been an issue for me from the first image I ever shot with my K10D. Actually, it started long before that, but the reality of it didn't hit home until I was holding the camera in my hands, trying to decide which was the best format for me to shoot in. There are a few questions here, not the least of which is image quality, but there is also file sizes and time consumption to consider. The DNGs produced by the K10D are nearly twice the size of the compressed PEFs. That being said, if you compress the uncompressed DNGs created by the K10 with the aid of Adobe's DNG conversion tool the DNGs themselves come out 1 MB smaller than the converted PEF using the same program. But, if you have to convert the DNGs from the camera in the same process you would use to convert the PEFs, then the point of having the ability to shoot DNGs in camera, and the use there of becomes somewhat pointless.
When it comes to image quality, I was truly surprised to see any major differences. Your take may differ from mine, but this is what I came away from the test with.
In the case of the DNG straight from the camera, and the compressed version, I saw no difference. This in itself is no suprise, because the DNG compression is a lossless process. However, when comparing the in camera DNG to that of the converted PEF-DNG the difference was striking. I shot this test several times, and each time I came out with the same results. PEFs showed noticeably better AWB performance, color rendition, and noise patterns. The images from the converted PEFs appeared crisper, smoother, and over all just better looking.
One of the biggest selling points of the K10D for me was the ability to shoot in the non-proprietary DNG format. I was proud of Pentax for taking this stand to say, no it's not just all about name brands and dollar signs, it is also about the needs of individual photographer who chooses to use our equipment or everyone else's. Well I can see now that this step was more lip service to an idea than the full implimentation of that idea.
So what does this mean? Well, what it means to me is that I will be shooting in the PEF format for now on and taking the extra step of converting my PEFs into DNGs, even though this can take hours depending on file loads, and I will be using twice the storage space to save them all.
I would like to make it clear that this is not a hate fest on the K10D or Pentax. It is just an honest look at the issue of DNGs Vs PEFs. I have "0" regrets about my choice to switch to Pentax, and I have even less regret than that about my K10D. This is a wonderful camera, and I see myself using it for years to come.
The following images were all shot at 1/60s, f/7.1, ISO 100, using the 18-55mm DA lens set at 21.0mm. The only processing rendered on them was a straight conversion from RAW to high quality JPEGs using ACR, and cropping of the overall image.
Judge for yourselves by checking out the full versions in the gallery, and please be kind, this is the first time I have shot tests like these.
Original in camera DNG...
Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut.