[bdery]

the K-3 sensor out-resolved it, leading to some loss of sharpness

That's a misconception. It actually means that you are using every bit of resolving power that the lens can offer. It also means that a sharper lens would give you even more resolving powerr.

There is no "loss". You could maybe say that some of the resolving power of the K-3 is "wasted" but frankly, with 24 MPs, it's pretty moot anyway.

[geomez]

I think the big question is how much more detail you see with the DA 55-300 on a K3 as compared to a K5. The answer is a little bit, but maybe not as much more as you'd expect. I haven't really shot my 55-300 much on the K3 -- it just has been too cold here, but my impression would be that if you stop it down to f8, you will see nice resolving power in the center, although borders may still be a bit weak (at 300mm). A lens like the DA *60-250 or 300 will not require stopping down nearly as much to get good sharpness throughout. The question, I suppose, is what you are shooting and how much you want to spend on a new piece of glass.

I've got a K-5, K-3 and DA 55-300. Looks like I've going to have to put my lab coat on and do some home testing

[normhead]

You know all these questions of the K3 out resolving lenses can be out to bed with a simple wander over to the Q forum and legacy lenses on the Q.

Considering the crop factor of 5.6, and the 10mp resolution, the q has a tone more pixels and resolution than the K3. People are taking amazing shots with 60 year old lenses on the Q and I don't hear talo of outresolving lenses yet

Exactly, I'm actually considering a Q7 and adapter for my A-400.. the image I posted with the purple fringing, my buddy standing beside me with his 850mm equivalent Canon point and shoot got a much better image. Me carrying my camera bag and 400 and 1.7 TC, up a frigging hill to get the shot, and him strolling along with his camera hanging around his neck. Sometimes life just isn't fair.

My guess is you'd get between 10 and 20% more resolution on a K-3. You just have to realize that in photography, one stop is double or half, so 10-20% plus 1/10 to 1/5th may not look like very much.

[mtngal]

I've begun to believe that for some unknown reason (and not necessarily AF issues) some lenses play nicer with some cameras than with others. I got my DA55-300 after I already owned the DA*300 and made the mistake of taking some comparison shots with the K5. I don't know if it was the comparison between the two lenses or if my particular K5 and DA55-300 didn't play well together, but I never used the lens because I was always disappointed in the results. It lived on a K7 that my husband used when we were on vacation, and he got a lot of excellent shots with it. When I got the K3 I sold the K7, and considered selling the DA 55-300, believing that it wouldn't be any better on the K3 than it was on the K5. This time I didn't try to compare the lens with anything else, just took a bunch of photos to see if it was focusing right and to see just how bad it was on the K3. I was very pleasantly surprised, the photos were quite useable and the lens now lives with my small walk-about stuff. It has its limitations and I won't shoot with it if I have the DA300 with me, but I find it a much more useful lens with the K3 than I had when I was using it on the K5. Or maybe I've gotten a better idea of what it's strengths are, and am shooting to them. In any case, I'm finally happy that I own it.