Hi. I love my SL and have become quite attached to it in the year since I've had it but I need a question answered. I recently compared some meter readings taken with my SL against readings taken with a Gossen Lunasix meter followed by a Nikon F90. It appears that my SL disagrees with these other two units by asking for a full stop worth of overexposure [ie. SL asks for f5.6 where the other two indicate f8.] Does this mean that the diode is dying? This hasn't posed much of a problem for my snap-shots from a practical standpoint as I am erring on the side of overexposure and most noticeable/unprintable mistakes in photography are the result of underexposure. Should I get the thing replaced immediately or just keep shooting as if I had a built-in +1 exposure compensation? What further problems [if any] related to this are in my immediate future? Any thoughts would be appreciated. Thanks in advance. Bo

-- Bo Pryszlak (natabo@aztec-net.com), January 07, 2001

Answers

Question: what type of battery are you using? If you have replaced the Mercury (PX625) with an Alkaline lookalike (PX625A) this would definitely result in an inaccuracy. Similarly, if your SL was "converted" to take the Alkaline cell an inaccuracy will still develop as the battery discharges because Alkalines change voltage as they discharge (Mercury, Silver Oxide and Lithiums don't). Lastly, it is not unusual for one meter to disagree with another one. If the amount of disagreement is constant, and you trust the F90 or Gossen to be correct, then simply set the ASA dial on the SL to double that of the film in use (eg set ASA 200 with ISO 100 film) and you'll get back to the correct reading. As a rule when match-needle meters like the SL's are "going" they get erratic or jumpy. In any case, watch it and if things get worse you'll be happy to know that I was told by Leica NJ a few months ago they still have parts for the SL's electronics.

-- Jay (infinitydt@aol.com), January 08, 2001.

The battery may be dying in which case you probably may not have a real mercury PX625, as these give out very rapidly. Have you checked the battery check button? You may need to get a new onen (or try a zinc-air equivalent), or you need to buy the adapter that converts the camera to the "modern" silver oxide S76. Another thing might be that the SL meter is not sensitive at low light levels, so may well be inaccurate if you are comparing the reading at low light levels. From what I remember I got wary of readings below 1/30 at f2 with EI 50 film. Otherwise the SLs meter is very reliable.

-- Robin Smith (rsmith@springer-ny.com), January 08, 2001.

Do not check your meter against other meters! Check it using slide film and scenes with grey cards. As the old saying goes, "A person with one watch knows what time it is but a person with two watches does not." Very seldom will two meters agree. My Minolta IVF comes with a calibration dial so that you can match another person's meter if you have too (film production say). Learn your meter and how to interpret its readings. You have to do this with any camera! The SL takes 1.35v batteries so use the ZnAir batteries if you cannot find the mercuries. Silver or alkaline cells have a higher initial voltage (1.5v) and a different discharge curve. They will be accurate only for a short while. Having said all that, CDS cells, such as are in your SL, can be changed if they are defective.

Cheers

-- John Collier (jbcollier@home.com), January 08, 2001.

I should clarify that the "CDS cell" is the light sensor in the camera not a battery.

Cheers

-- John Collier (jbcollier@home.com), January 08, 2001.

Thanks for all of your responses. I took the SL into the camera shop I deal with. The owner is a former Leitz Canada technician and he examined the body. According to him, if the meter were beginning to fail the needle would be either erratic or perhaps sluggish. The battery test button indicated a very strong Varta PX 625 in the chamber but when we compared readings with my SL with those of another SL in the shop, once again my SL showed a 2-stop overexposure at f2 [low light reading, obviously] and about a 1 to 1.5 stop overexposure at the high end. I have been assured that he will be able to make the necessary adjustments [behind the 'SL' coverplate] to the meter and that such servicing is rather simple to do and not anything to get overly alarmed about. I suppose, after all, a 30-year old camera might need the odd bit of tuning periodically. Any further thoughts out there are always welcome. Bo

-- Bo Pryszlak (natabo@aztec-net.com), January 08, 2001.