Ian Fleming <[EMAIL PROTECTED]> wrote:
>I have noticed that my MX ,bought used,does not quite make infinity
>on focusing,I have tried the lenses in my LX and they are OK.I have
>tried reseating the focussing screen to no avail.any ideas?
>A service is in order I suspect.
Either or both of two things that could be wrong: The position of the focusing
screen or the film-to-lens-flange distance (the latter is set with shims between
the camera's lens flange and the camera body).
You need to give a little bit clearer description of the problem you're having.
Find a subject far enough away to be accurately in focus when a 50mm lens is
focused at infinity (check with another camera). Mount the 50mm lens and set it
wide open (maximum aperture) and focused at infinity. Take some pictures. There
are three possibilities:
1) The viewfinder image is out of focus but the exposed image on the film *is*
in focus.
-- This would mean the focusing screen position is out of adjustment.
2) Both the viewfinder image AND the exposed image on the film are out of focus.
-- This means the film-to-lens-flange distance is wrong and shims need to be
changed to correct it.
3) The viewfinder *shows* that the image in focus but what comes out on film is
NOT in focus.
-- This means that the film-to-lens-flange distance is off and that someone
has foolishly adjusted the focusing screen to try to compensate.
--
Mark Roberts
www.robertstech.com
-
This message is from the Pentax-Discuss Mail List. To unsubscribe,
go to http://www.pdml.net and follow the directions. Don't forget to
visit the Pentax Users' Gallery at http://pug.komkon.org .
