Yes, it is interesting. I'm going to recheck my FA50/1.4. The target I used with my FA35/2 was better than the one I used previously, so it was easier to pick the best frame. But in picking the best frame, the difference is so slight, I have to go to at least 100% magnification of a hi-res image to see the focus variation from one step to the next. And even then, it requires close scrutiny. It can't be seen in the on-camera display, even at highest magnification. So a lens that's off by one or two steps on the K20 scale is still quite acceptable, and the difference wouldn't be seen in normal viewing of a print. But it's nice to know that they can be zeroed in.
I'll also be curious to see if they change after a few months of use. Could be normal wear and tear causes some slight variation. Paul -------------- Original message ---------------------- From: "Steve Desjardins" <[EMAIL PROTECTED]> > This is pretty interesting. I've never really noticed any BF or FF > problems, but I tend to use my FA 20-35 or my 50 1.4 in daylight. Dof > probably saves me. I'd be really curious to know how much this > adjustment differs from, say, one FA 50 1.4 to another. > > >>> Paul Stenquist <[EMAIL PROTECTED]> 3/4/2008 7:10 AM >>> > I think most lenses will benefit from some fine tuning of the focal > point. Although it remains to be seen how accurate the DA lenses > might be. The kind of adjustments I'm making are quite fine, and the > difference isn't critical for most subjects. About the only place > where it comes into play is with wide-open portraits, where eye focus > > is critical. Of course, those should be manual focused anyway in the > studio. But for situations like wedding photography or even my coffee > > shop portraits, pinpoint autofocus accuracy is an advantage. "A" > lenses aren't autofocus, of course, so they just sit there silently > without complaint:-). > Paul > On Mar 4, 2008, at 6:48 AM, David J Brooks wrote: > > > So it seems the older F and FA lenses may have some fine tuning > then. > > > > Wonder what the A lenses will do, i have more of them than F and FA > > > ones. > > > > I hope by adjusting my K10D i did not throw things out of wack. But > > then again i panic about things like that,:-) > > > > K20D will have to wait. I'm more interested in getting a good F2.8 > or > > F4 zoom for the horse ring. I plan to make the K10D the mane camera > if > > a lens comes out soon enough. However if i make money early on my > > shows, i might have enough for both > > > > Dave > > > > Dave > > > > On Mon, Mar 3, 2008 at 9:35 PM, Paul Stenquist > > <[EMAIL PROTECTED]> wrote: > >> I've now adjusted focus for two of my lenses, the FA 50/1.4 and the > >> FA 35/2. The FA 35/2 came in at +2. The FA 50/1.4 came in at -3. > So > >> it seems that it's more a matter of lens variation than camera > >> baseline. I haven't tested the DA lenses yet, but they appear to > be > >> spot on in informal look sees. For adjustment I shoot a crisply > >> printed sheet off a tripod. I run the range from -6 to +6 in > >> steps of > >> two. When I have the winner, I do one step in each direction. It > >> only > >> take a few minutes. It makes me think that an overall adjustment > >> is a > >> real compromise. Lens specific is great. Another big plus for this > >> camera. > >> Paul > >> > >> -- > >> 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. > >> > > > > > > > > -- > > Equine Photography > > www.caughtinmotion.com > > http://brooksinthecountry.blogspot.com/ > > Ontario Canada > > > > -- > > 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. > > !SIG:47cd3c8c241441053587964! > > > -- > 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.
