Originally posted by SteveinSLC 
I have a DA* 300 (as well as a DFA* 70-200) but neither of those really qualifies on the light and easy to tote around scale in my eyes, though both are excellent optically. I was hoping this would be a cheap and light option, with at least decent quality for hiking and travel. And it's certainly possible I got a bad copy.
I was shooting out at Antelope Island in the Great Salt Lake, where there are both bison and pronghorn antelope. The bison were actually too close to the car for the DA*300, so the 70-300 seemed a good choice. And it was for the close bison, but later when trying to get shots of some pronghorn butting heads about 50m away at 300mm zoom, the shots were very soft in good light with a fast shutter speed(and I don't have those kind of focus issues with the K-70 and DA*300). I was not pleased because sharp pics of the antelope butting heads would have been very nice. Still working to see if I can save them in Lightroom.
I would say that beyond 200mm you're best to stay around f11 with either the 55-300 or 70-300, and even at that you're not going to get extreme resolution. However I've needed no microfocus adjustments on any of my bodies with either lens. I would test with a static target in controlled conditions so you can know what to expect - keeping in mind you won''t get DA*300 quality except by using a DA*300 (or one of the few similarly-performing high-end lenses.) I do get better results, even on my 16mp camera, with the 60-250 cropped to be a similar view as one of the less expensive zooms at 300 for distant subjects, and I don't have to stop down to f11.
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