Olympus-OM
[Top] [All Lists]

[OM] Re: OM lens mount to film plane distance

Subject: [OM] Re: OM lens mount to film plane distance
From: Moose <olymoose@xxxxxxxxx>
Date: Sun, 20 Apr 2008 03:32:10 -0700
C.H.Ling wrote:
> Sorry, Moose. 0.19mm (46.08-45.89) difference seems a lot! 
Yeah, I agree, and I may have exaggerated it by using the largest 
possible measuring error
> I remember Canyon New F1 claimed they controlled the tolerance to 0.02mm. I 
> just made some measurements on an OM1n and OM2n, the four corners of the 
> guide rails are no more than 0.035mm difference, this already included the 
> errors from my not so flat table (but I did measured more than two times at 
> different locations of my table).
>   
My table's pretty flat. And maybe I grabbed a worst case body at random. 
I didn't just take corner reading, but also middle and in between. In 
the case of a casting, assuming that dimensional distortion will be 
linear, rather than radial, isn't necessarily a good idea. I don't 
recall which were which, as my point was simply that obsessing about 
whether the nominal register distance is perfect is wasted effort.

As long as you bring it up again, I'll add viewfinder optics, mirror 
position accuracy and precision of focusing screen positioning to film 
characteristics and film flatness as factors that contribute to focusing 
accuracy beyond register distance precision.

If one has a problem with focus accuracy, it's worth tracking down which 
of multiple factors contribute to it. Other wise, take pictures, be happy.

Moose

==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz