Two Tips- Lens Mounts and Rear Filters

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If you use your 67 for many years, you will start to have connectivity problems between your TTL meter and your lenses(that is if you have an in camera meter). This is caused by dust, oils and slight oxydation of the lens mounts, both inner and outer bay. You will find that one day your meter just doesn't work. What needs to be done, is to clean the mounting bays and the mounting surfaces of all your lenses. Make sure you clean the lens locking pin and the metal tab in the lens mount. The tab is at the 9 o'clock position when looking into the camera. Also clean the metal lever located at the 11 o'clock position. When using the outer bay lenses with rear filters in place, remember that infinity focus(and all others) will be shifted to the rear. So, if you are using the 400mm Takumar as an example, infinity will actually be shown closer to 700 feet or so rather than at infinity. This can make the use of the DOF scale quite difficult. Instead of setting the infinity mark on your F-stop on the barrel, you need to set it at what has now become the new infinity mark. If the DOF scale on the lens is not all that accurate in the first place, then you can see the challenge this situation becomes. SR

-- Steve Rasmussen (srasmuss@flash.net), March 13, 2000

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