On Feb 7, 2011, at 7:47 PM, Igor Roshchin wrote: > > Mon Feb 7 18:22:50 CST 2011 > Paul Stenquist wrote: > >> On Feb 7, 2011, at 7:16 PM, Igor Roshchin wrote: >> >>> Also, albeit very subjectively (i.e. without quantitative and >>> systematic >>> tests), I found that 17-70/4 tends to produce somewhat sharper images >>> of >>> the dancers than 16-50/2.8 even at f/4 or f/5.6. >>> The only way I can explain this is by different quality (or speed?) >>> of focusing. >>> I've been puzzled by that myself, and that why I chose to keep 17-70/4 >>> last year. >> >> Sound like critical focus isn't properly adjusted for the 16-50. Have >> you tested and adjusted the focus point? >> > > No, I didn't, and I realize that. But I just didn't have time and energy > to deal with that. > (I didn't do any focus adjustments on any lenses mentioned here.) > > The first sample of 16-50/2.8 was showing worse results, so I just sent > it back to the store. > The second is much better if not good, as I don't seem to have > obvious problems with photos of static objects (e.g. portraits of people > sitting/staying, etc.). ... maybe not.. as photos taken with 50-135/2.8 > in the same situation with the same subject appear noticeably sharper.
Adjusting focus with the K20D is a virtual necessity. Most of my lenses missed by quite a bit with that camera. Paul > > Igor > > > -- > PDML Pentax-Discuss Mail List > [email protected] > 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 [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
