On Feb 10, 2011, at 5:09 AM, Larry Colen wrote: > I've always had mixed feelings about my pfa 50/1.4. There have been times > when I really needed the extra 2/3 stop of speed that it gave me over my > f/1.8 glass. When you're shooting slower than 1/15 second and your subjects > are moving, that's a critical difference in speed. On the other hand, I never > really gained any affection for it. When I use a super tak 50/1.4 I can > forgive it a lot because of the beautiful way that the manual focus feels. I > bought my DA 40 for its size, but quickly grew to love the pictures it took. > If my FA77 were a woman, I'd be tempted to propose marriage. But the PFA > 50/1.4 is almost the dirty little secret in my lens bag. When I need it, I > use it, but I almost never just put it on the camera to go shooting. I'm > more likely to grab the DA40, or especially now, the 16-50. > > A week or so ago, I took some shots that made me wonder if something might be > wrong with it. I was also using a teleconverter at the time, so I wasn't > going to automatically blame either piece of glass. I just spent some time > doing some trivial sharpness tests, and it turns out that between f/1.4 and > f/2.0 it gets a lot better, and much better yet by 2.8 Which, I guess, is > the reputation of the lens. Soft wide open, but reasonably sharp if you stop > it down a bit. > > I suppose there are a couple of reasons I hadn't really noticed this before. > The first one is that when you're pushing the sensor as hard as you can, and > shooting at some stupidly slow shutter speed, the loss of sharpness from > running the lens wide open was barely going to be noticed. Another likely > reason is that I don't actually spend a lot of time pixel peeping, and as > glaringly obvious as something might be at 2:1 on a 24" monitor, it may not > be nearly as obvious under normal use. > > So, I guess that there really isn't anything wrong with the lens, and now I > think I know why I never really fell in love with it. For that matter, the > ridiculous sensitivity of modern sensors are going to pretty soon make it > totally unnecessary to shoot with any glass faster than f/2.8. But, part of > me is still rather disappointed at how sharply performance dropped off at the > wide end.
Did you manual focus? If you're shooting wide open, and your autofocus is off by even a relatively small amount, your results will be soft. The performance of this lens on my K20 is what first convinced me that fine focus adjustment is a necessity. I've since seen that the FA50/1.4 required more adjustment than any of my DA or DA* lenses. Paul > > > -- > Larry Colen l...@red4est.com sent from i4est > > > > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
