[rollei_list] Re: 6 x 9 search
----- Original Message ----- From: "Jerry Lehrer" <glehrer@xxxxxxxxxx> 
To: <rollei_list@xxxxxxxxxxxxx>
Sent: Thursday, August 30, 2007 10:09 PM
Subject: [rollei_list] Re: 6 x 9 search



Mike,
Even an idiot like me knows that there are different cams for different FL lenses. Think about it. 

Jerry
The Kalart side mounted rangefinder is a fascinating bit of engineering. It has a two section cam and several adjustments (some are internal factory adjustments) to allow it to approximate the cam curvature needed for a fairly wide range of focal lengths. When properly set up and adjusted the Kalart is remarkably accurate. Its interesting that the patents state that it was not intended for very close focusing. I think this is bacause the parallax between the rangefinder and taking lens becomes relatively great. However, even given this the thing is pretty reliable down to about six feet on a 4x5 camera. I can get mine to track to 4 feet. This takes some juggling if any of the adjustments has been changed. The mounting and infinity settings are very critical. There is an internal infinity setting that must be right on if the rangefinder is to track accurately over its range. Another thing I have found is that the focus shift from spherical aberration is enough to throw off the adjustments if the lens is set up wide open. This varies a lot with different lenses. Some have very little focus shift. The same thing can cause problems wtih a TLR camera. 

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx 
---
Rollei List

- Post to rollei_list@xxxxxxxxxxxxx
- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org
- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org 

- Online, searchable archives are available at
http://www.freelists.org/archives/rollei_list

Other related posts: