WRONG WRONG WRONG- Just because you get all your pictures in focus ( I still have no problem with that on my ancient spotmatics ) doesnt mean that the wider lenses are not ANY harder and/or took longer to focus accurately. I will not back down on this and I insist you are incorrect if you still believe that a lens does not get harder to focus the wider it gets, all else being equal. How much harder is going to depend on a lot of things but it will never be exactly the same difficulty becuase of the simple fact that wider lenses have more DOF at same f-stop and distance than longer lenses. The difference is directly related to the difference in focal lengths. I suggest you try a 20mm at f8 and a 200mm at f8 and see if you still come to your same conclusion because it will be easier to see the effects of the DOF differences and hence the focussing ease differences. If what your are contending is true, then it wouldnt matter what focal lengths so the 20/200 example is better test to prove the point. jco
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Shel Belinkoff Sent: Tuesday, November 14, 2006 10:02 AM To: Pentax-Discuss Mail List Subject: Re: Using a Super Tak w/ istDS- A challange to the list? No one is arguing this point. All Bill and I said is that we found it just as easy to focus a particular wide lens as a particular long lens on the D and the DS, physics and science notwithstanding. It was after that that "someone" said we were liars and that we were mistaken, etc. The thing is, rarely if ever are all things equal, and even if everything in the compendium you posted was equal, there's the human element to consider, and no two people are ever equal. There is no personal opinion wrt our experiences. They are absolute. We put the lenses in question on the camera, stopped them down, and focused. Our comments reflect our experience. In fact. neither Bill nor I have argued against the premise put forth by JCO. All we did was report what we found in our particular situations. I have since tried the with a couple of other lenses, and in every instance I found it just as easy to focus a wide lens as a long lens on the istDS. The pics I took are all equally in focus. Perhaps those of you relying on science and physics should pick up a couple of appropriate lenses, stick 'em on your istD or istDS, and see what your results are instead of quoting the laws of physics, which you did with a large list of qualifiers. Shel > [Original Message] > From: Cory Papenfuss > > You're correct on this JCO. Bill Robb is bating you. Ignore him and > > he'll stop. > > Paul > > Agreed. > > Everything else being equal (aperture, contrast, resolution, > helical gear cut, etc), a longer focal length (e.g. 105mm) will have a > higher "focusing sensitivity" than a wide angle (e.g. 35mm). That's just > plain physics. > > Anyone trying to argue otherwise (e.g. Will Robb) is either > ignoring one or more of these factors, or using the "personal opinion" > argument, to which there is no refute. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
