Archived posting to the Leica Users Group, 1997/08/30
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I do have one of the astigmatism correction eye-piece lenses. It does help when I'm not wearing my glasses. However, it's a waste of time. Shoot with your glasses on. When you use an astigmatism correction eye-piece on your finder...you must change the orientation when you shoot vertical pictures, if it's set for horizontal ones, and visa versa. Ed Meyers On Sat, 30 Aug 1997, Michael Goldbard wrote: > Richard, > > Thanks for the informative posting. Perhaps you or another LUGger might be > able to answer some related questions. > > At one time Leitz sold astigmatic corrective lens and I believe that they > were supplied in a rotating mount. The rotation enabled the M camera user > to maintain the proper orientation of the corrective lens when using the > camera in a horizontal or vertical position. > > >From what I've read, it appears that only a blank mount is now supplied. > Does the blank mount rotate in the same fashion as the previous astigmatic > corrective lenses? Is such a lens convenient or does the necessity of > rotation disturb the flow of shooting? > > Thanks to all for the making the LUG such a great resource. > > Michael > > > Richard Clompus wrote: > > >With astigmatic corrective lenses, you must not only deal with the strength > >of the lens but also the orientation. Orientation is described as the axis > >and is expressed in degress (starting at 0 and going up to 180.) An > >astigmatic prescription is then expressed as -1.00 diopter X 180 so that it > >describes the strength (-1.00 diopter) and orientation (axis 180). The > >astigmatic eye piece corrective lens must be turned and locked into the > >correct position. If it gets turned even 10 degrees from where it should > >be, your vision will be blurred. Make sure that the eye piece is marked so > >you know the final orientation on the camera. This way the optician can > >insert the lens so when you tighten the eye piece ring, it lines up the > >proper way. > > > > >