Reading mode: Light Dark

5D II: mirror hits Pentax FA 20mm + adapter

Go to last post
C

Chris_LC

New member
Messages
2
Reaction score
0
Location
Menlo Park USA, CA, US
FYI:

I have a Pentax FA 20mm f2.8 upon which I performed a full leverotomy (Pentax K diaphragm lever sticks out). If the lens is focused at infinity, i.e. the lens is fully retracted into the mount, the mirror gets blocked by the edge of the back optical mount. People pictures work OK as the lens moves forward as one focuses closer.

The blocked mirror snaps back in place when one unmounts the lens.

I know some people grind the edge of their mirrors, but I am not prepared to do that on my new toy :-)

Apologies if that info was well known, I did not find any reference when I looked for it.

Christian

PS On that lens the lever surgery is reversible, 2 screws for the lever, 3 screws for the back shield.
 
Thanks for the interesting info Chris... although I don't think I'll be using that particular lens, I'm interested in knowing whether you've tried your lens on the original 5D without this problem.

GTW
--
http://www.flickr.com/genotypewriter
Chris_LC said:
FYI:
I have a Pentax FA 20mm f2.8 upon which I performed a full leverotomy
(Pentax K diaphragm lever sticks out). If the lens is focused at
infinity, i.e. the lens is fully retracted into the mount, the mirror
gets blocked by the edge of the back optical mount. People pictures
work OK as the lens moves forward as one focuses closer.

The blocked mirror snaps back in place when one unmounts the lens.

I know some people grind the edge of their mirrors, but I am not
prepared to do that on my new toy :-)

Apologies if that info was well known, I did not find any reference
when I looked for it.

Christian

PS On that lens the lever surgery is reversible, 2 screws for the
lever, 3 screws for the back shield.
Click to expand...
 
Chris_LC said:
I have a Pentax FA 20mm f2.8 upon which I performed a full leverotomy
(Pentax K diaphragm lever sticks out). If the lens is focused at
infinity, i.e. the lens is fully retracted into the mount, the mirror
gets blocked by the edge of the back optical mount. People pictures
work OK as the lens moves forward as one focuses closer.

The blocked mirror snaps back in place when one unmounts the lens.

I know some people grind the edge of their mirrors, but I am not
prepared to do that on my new toy :-)
Click to expand...
Ouch! You do realize the contruction of the mirror mechanism is not designed to withstand impact to the back of a lens? And you understand that the positioning of the mirror is critical for the proper functioning of auto-focus?

--
Mike Mullen
 
You must log in or register to reply here.

Keyboard shortcuts

f
Forum
m
My threads
Mobile site
About
Editorial content
Cameras & Lenses
Community
All content, design, and layout are Copyright © 1998–2025 Digital Photography Review All Rights Reserved.
Reproduction in whole or part in any form or medium without specific written permission is prohibited.
When you use DPReview links to buy products, the site may earn a commission.
©GPS Media - Guides, Products, Services.
Back
Top