On Thu, Dec 01, 2005 at 04:15:49PM +0000, Kostas Kavoussanakis wrote: > On Tue, 29 Nov 2005, Godfrey DiGiorgi wrote: > > >Be aware that the difference in field of view between 90 and 105mm is > >quite small. See > >http://homepage.mac.com/godders/2zmFoVcomp.jpg > >for comparison. The real advantages of the 24-90 are much more field of > >view at the wide and and better performance when wide open at the tele end. > > Thanks, Godfrey. Can you help me understand your diagram? Is the > small, green rectangle the FOV at (more or less) 90? Here is an > exercise I would like to solve: "Assuming a lens at 90mm and another > at 105mm, how much closer to the subject should one go so as to get a > photograph with the same dimensions on the recording medium".
Well, that's easy. You should move forward until you're 90/105 of the distance you started from.
