Olympus-OM
[Top] [All Lists]

Re: [OM] Spotted another rare CV 180 in OM mount --Big Foot'slonger brot

Subject: Re: [OM] Spotted another rare CV 180 in OM mount --Big Foot'slonger brother
From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
Date: Thu, 04 Feb 2010 12:33:35 -0500
The subject of the referenced paper has to do with shooting panoramas 
and validating that the "no-parallax" point of a lens is the "entrance 
pupil" and not one of the "nodal points" as is frequently (and 
incorrectly) stated.  It also demonstrates that the aperture itself 
determines the perspective of the image since changing the size or the 
position of the aperture (while changing nothing else) can shift the 
position of out-of-focus elements in the image.

 From the standpoint of a single macro photo (vs a macro pano) I don't 
think it has any bearing on your off-center aperture except that the 
out-of-focus parts of the image would be slightly displaced from where 
they would otherwise be.  Nothing you could notice.  However, I would be 
concerned about the accuracy of the aperture and especially at small 
openings.  I don't know what would cause it.

Chuck Norcutt


Ken Norton wrote:
> I created a link to that article on the zone-10 site as I'm needing to
> digest it. But it does bring up something that I've been all concerned over.
> 
> My 50/3.5 lens has an offset aperture. The aperture diaphrams are not
> centered in the optical path and are visibly out of alignment. I'd guess
> that it's off by the diameter of the opening at F11 or F16. My questions are
> two-fold:
> 
> 1. Does it matter?
> 2. How difficult is it to fix?
> 
> AG (bent out of shape) Schnozz
-- 
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/

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