Archived posting to the Leica Users Group, 1999/10/06
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]From: Kotsinadelis, Peter (Peter) <peterk@lucent.com> Sent: Wednesday, October 06, 1999 17:50 Subject: RE: [Leica] Shooting Leica wide open > With all due respect, no lens performs better wide > open than stopped down. I assume, though, that this is because a wide-open lens uses all the glass in the lens, and the perimeter of the elements and the way they affect light can never be optimized to the extent that the central portion of the elements can. If so, then it seems that the wider the maximum aperture of a lens, the wider the stop at which it reaches a given level of performance, all else being equal. That is to say, a lens will always tend to perform best at wide open - d stops, where d is a constant. So a lens that opens to f/1.4 might perform best at f/5.6, whereas a lens that opens to f/2.8 might perform best at f/11. A faster lens not only would give you a larger maximum aperture, it would also give you a larger and/or faster range of optimal performance. Does this make sense? -- Anthony