Archived posting to the Leica Users Group, 2003/08/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]on 8/26/03 6:49 PM, Afterswift@aol.com at Afterswift@aol.com wrote: > > In a message dated 8/26/03 5:13:37 PM, rhc3vt@hotmail.com writes: > > << The Micro-NIKKOR-P 3.5/55mm, for one. Can you explain the effect of > diffraction on a lens such as the 9cm Elmar? >> > > I have a Micro Nikkor 2.8 that does have an f32. I never noticed it because I > never needed to use it. However, it is remarkable that both the Leitz 90 f4 > and the Micro Nikkor seemed to have overcome diffraction, even all those years > ago. I certainly will hold onto those two lenses. > > br > It's not that they have overcome diffraction. Whether f/32 is available or not is a design compromise, to allow a greater depth-of-field and accepting a softer overall image as a consequence. If a lens is extremely well-corrected for other aberations at small apertures, the design team may allow f/32 if the diffraction effects don't soften the image as much as a less well-corrected lens might at a larger aperture. There is no avoiding diffraction. Doug Herr Birdman of Sacramento http://www.wildlightphoto.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html