Thanks Dario! I was about to go have my eyes checked again. As a computer guy who makes frequent calls to various support lines my most hated response is:
"Gee, we've never seen that before but if you figure it out let us know!" I'm glad to hear someone else has seen this wierd behavior. Don > -----Original Message----- > From: Dario Bonazza [mailto:[EMAIL PROTECTED] > Sent: Monday, April 04, 2005 8:40 AM > To: [email protected] > Subject: Re: HELP! DA vs 28s-One More Time. (longish) > > > It happened a few times to me: I carefully focused on a given spot and a > particular combination of camera+lens was actually focused elsewhere > (usually focused far closer to the camera than expected). > > In my experience, risky combos are: > > 1) MZ-S + FA* 85/1.4: two different lenses tested on the same > camera, giving > more or less the same result. All other lenses perform well (perfectly > focused) with that same camera. > > 2) *istD + F 70-210 (only at longer focal lengths=180 to 210mm): three > different cameras and two different lenses tested, giving more or > less the > same result. All other camera+lens combos worked well. > > See my page: http://www.dariobonazza.com/t04p13e.htm > Please look at the whole picture around mid-page (to see the different > distances of the roofs) and then scroll down to see how the crops turned > out. > > Please notice that the same camera > > Dario > www.dariobonazza.com > > > ----- Original Message ----- > From: "Don Sanderson" <[EMAIL PROTECTED]> > To: "PDML" <[email protected]> > Sent: Sunday, April 03, 2005 9:57 PM > Subject: HELP! DA vs 28s-One More Time. (longish) > > > > OK, here's that roof again. > > 2 shots with the DA 16-45/4 at 4.0 > > 1 with the M 28/3.5 at 3.5 > > 1 with the A 28/2.8 at 2.8 > > All upsized to 300% > > All treated *exactly* the same way from exposure to web. > > > > http://tinyurl.com/4axt4 > > > > **I CAN SEE, in the viewfinder, (with the 2x) detail in > > the shingles *far above* what shows in the DA samples! > > Both of the 28s give me what I expect, but not the DA. > > > > If someone else had processed these for me I would have > > accused them of intentionaly blurring the DA samples! > > > > I'm at a total loss to explain how I can see a highly > > detailed image in the viewfinder with all three lenses > > but only two of them give a detailed final result. > > > > > > Rob, in one of your posts you said: > > > > "Har told ya, also I suspect any visual focus error on > > the DA is likely due to a spherical field of focus." > > > > What exactly does that mean? > > Can a viewfinder and focus confirmation signal actually > > be wrong for one lens and OK for others? > > A D viewfinder is too small to be really critical, but > > with the 2x magnifier detail in the roof is very clear. > > > > I used the 2x for all shots on all three lenses. > > I used a sturdy tripod, placed the same for each. > > I used mirror pre-fire for all of them. > > I used 1/2000 or 1/4000 shutter speeds. > > 3 were focused manually, on the DA shot labeled > > "Take Three" I allowed the D to autofocus, it missed. > > I even focused ahead of and behind the lower pipe to > > see if it made a difference, it did, all those shots > > were worse, DA and 28s alike. > > I am 100% certain these are correctly focused and > > camera shake is not a factor. > > Lighting is a bit different in the M shot. > > > > What the Heck is going on here??????? > > > > Don > > > > > > > > > > >
