Archived posting to the Leica Users Group, 2010/11/07
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I have tested it. There is absolutely visible focus shift, but not as Howard describes in the middle image distances. It occurs at you stop down between close focus and 3-4 m; past that the depth of field is sufficient to mask it. It is the chief disadvantage of the 90 AA; on digital in particular the stopped down close focus performance really suffers and you can clearly see why Leica started making lenses with floating elements. And as always, if the camera and lens are properly adjusted, the effect is minimised. Marty On Sun, Nov 7, 2010 at 10:23 PM, Frank Dernie <Frank.Dernie at btinternet.com> wrote: > I have not tried it with mine, don't like doing tests, but I have read a > thorough review on a subscription site to which I no longer subscribe, > showing the focus shift being greater than the depth of field at certain > focus distances and apertures. > IIRC it was either diglloyd or another who's name escapes me for a moment. > Anyway, I did not bother though I know others who gave up on it after > trying multiple adjustments and sold it. > FD > > On 7 Nov, 2010, at 11:23, Marty Deveney wrote: > >> The 90 APO has focus shift that is less that the depth of field. ?What >> Howard is seeing is not focus shift; something in his camera, or more >> likely his lens, is out of spec. >> >> Marty > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >