Archived posting to the Leica Users Group, 1996/12/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]If you read my suggestion, I don't suggest that he calibrate his meter using a grey card, only that he use it as a standard target (so to speak) to check the CL against a trusted meter. I wouldn't even suggest that he calibrate his camera. That is best left to a trained tech with the correct equip. I have only seen one meter, the SEI, which can be calibrated without specific equipment. I am not talking about zero adjusting a meter, which is not the same as a calibration. Your recommended calibration using an M6 is interesting provided the reference M6 were calibrated to a standard. While this would be truly wonderful, the ones that I've looked at are as much as an f/stop off. These are new cameras I am talking about. This variance has been observed with almost all other brands and models. I am not sure whether you actually are referring to the cell or the arm which the cell is on. While I have heard stories about the arm doing everything from falling off to being bent by people after they pop the lens, I have never heard these stories from people who had it happen to them. And since the arm swings out of sight when the lens is popped, I doubt those stories. Of course, if you don't pay attention to what lenses NOT to use, the arm could end up ventilating the shutter. The meter is not as protected against dust intrusion as could have been hoped for, but it doesn't seem any worse than most mechanical movements. M5s had 2 cells; the first was subject to premature failure and was replaced with a second type, which is the one used in the CL. It has proven reliable and trouble free. Some of the comments I've read have said something like 'Since the CL uses the M5's metering which is trouble prone, it also is prone to have an early and high failure rate.' (can't remember source of the line, can remember the impact of it when I first thought about purchasing a CL) Turned out the M5 and CL both were neither weak designs or failure prone. At 02:07 PM 12/24/96 -0700, you wrote: >LUGs, > >I recently reported on my experiences with calibrating light meters in Leitz >cameras. I find that the use of the gray card can lead to errors unless the >card is very large and focal length is long. > >My preferred method is now based on the use of a good lightbox, like the one >you would use to view high-quality slides. I then use my M6 meter and 90mm >lens as the reference. The same lens is used on the camera to be calibrated. > >I do not own a CL, but have heard that the original meter cells were not of >the highest quality. Personally, I like CdS meters. Too bad that the mercury >cells are no longer universally available. > >Have a great X-mas and don't forget to use your Leicas, > >Chris >At 03:27 PM 12/24/96 -0500, you wrote: >>The meter in the CL is very sensitive. >> >>When I first got mine, and even now if I haven't used it for a long while, >>the meter takes some getting used to. >> >>To see if the meter is out of calibration try the folowing: >> >>With either the 90 or 40mm lens meter a grey card covering the full imaging >>area at some ISO and note the readings. Now with the same lighting, use a >>trusted hand held meter and meter the same card. The readings should be the >>same. If not, note the difference. >> >>Since the camera is about 20+ years old, a metering circuit needing a CLA >>should not be a concern. Even a meter that is sticky is no great concern. >>You may want to contact Leica for a CLA estimate (I think mine was about >>$250 several years ago). Use it as a bargaining tool possibly to adjust the >>price. For those I have spoken to about this camera, I tell all that figure >>a CLA in the price. These cameras seem to be treated with more care than >>many others, but also seem to have been less used. This also means most are >>ready for a CLA. >> >>The area metered by the CL is not well defined in the manual, but does not >>seem to be bottom weighted and reads about 12% of the lens coverage >>principally centered about the center with less coverage to the left and >>right. Because of this shape, it seems to read (and change readings) more >>akin to a reading of less coverage. Also, the meter which reads underexposed >>when the needle is above the 'correct exposure' notch is somewhat >>disconcerting at first since this condition is opposite of most other >>metering systems. >> >>When I contacted Leica re: the 625 issue, I was told the metering would not >>be affected by the small difference in voltage. I did a quick comparison >>with my camera and found less than about 1/6th stop. Leica did tell me they >>could recalibrate the circuit. On my next CLA, I'll have it done to use the >>alkaline 625 since my other equip is being recalibrated for this standard >>voltage. >> >>Hope this addresses your concerns. The camera and its lenses are for me >>about as good as it gets since in 35mm, I use slightly wide angle to short >>telephoto focal lengths. The body is substantially smaller than the M series >>and with the 40mm attached is one mighty, great, hi quality and long termed >>systems made. Good luck. >> >> >> >>> >>Brian Levy, J.D. >>Agincourt Ont. >>dlevy@worldy.com >> >> >> > > Brian Levy, J.D. Agincourt Ont. dlevy@worldy.com