Luna Pro needs recalibration

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I lost my instruction book for my Luna Pro and I believe that the meter is off calibration...this assumption is based on a duplicate reading taken from another photographer's meter and I haven't used mine in almost 10 years. The battery is good. My instincts tell me to measure a grey card in sunlight i.e., f16 @ 250 ASA 250 - hm-m-m or is it f22???? You can see why I'm asking...a little rusty! Any thoughts??? Does Gossen have this info on-line?

-- Frank Kamm (CF2@aol.com), July 11, 1999

Answers

Comparisons between meters can show as much as 2 stops difference between two meters of the same mfg. I would suggest running a short roll of b/w film photographing a gray card keeping record of each exposure and meter reading and then develope and print to see which exposure give you the best rendition of the 18% gray card. Not being a color film shooter myself, I would suspect that you could do the same with color film, as far as b/w goes it does not matter if the meter is off a stop or even two, what matters is that it is consistant and then you can work with it. If it is not consistant then you have a problem. Pat

-- pat j. krentz (krentz@cci-29palms.com), July 12, 1999.

2 stops off is a bit much. Are you sure the batteries are ok because the newer non mercury 625's won't work in a Luna Pro. The needle has to be centered in the red zone when testing. They sell an adapter that takes a readily available silver oxide battery and corrects it to the proper voltage. George

-- George Nedleman (gnln@thegrid.net), July 12, 1999.

Frank, If your meter needs work or recalibrating, I've had good luck with: Quality Light Metrics 6922 Hollywood Blvd. Suite 210 Hollywood, CA 90028 (213) 467 2265 Good luck, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), July 12, 1999.

George, the 2 stops difference is not my guesstamaiton, it is an existing fact for meters of the same mfg. and model. I second Doremus on his suggestion for recalibration. Or you might see if Zone VI is still doing conversions for the luna pro, I know the old Luna Pro, got mine in 85 takes a 1.3v battery, which Freestyle sells. Pat

-- pat j. krentz (krentz@cci-29palms.com), July 12, 1999.

I have to second the suggestion you send it to Quality Light Metric, they do fabulous work at reasonable prices.

-- Jim McDonough (jmcdonough@prodigy.net), July 12, 1999.


There's no "zero adjustment" on the old Luna-Pro? The Luna-Pro SBC has a screw in the back to re-adjust the needle to the appropriate zero position.

-- Sean yates (yatescats@yahoo.com), July 13, 1999.

Sean, excuse me if I disgree with you, there is a slot in the back of the old Luna Pro's for Zeroing the meter. Pat

-- pat j. krentz (krentz@cci-29palms.com), July 14, 1999.

Pat, please look closely. You'll notice that was a question?

-- Sean yates (yatescats@yahoo.com), July 14, 1999.

The original Luna Pro took two PX-13 Mercury batteries. I bought one of those kits from Bogen (the current distributor) and found, after spending $18, that it didn't work. No amount of fiddling with the zeroing screw helped. I then got 2 Varta 625 PX replacements for the PX-13's and was able to once again, zero my Luna Pro and have it match, within a 1/2 a stop, all my other meters. The zeroing procedure, according to my original manual, is to remove the batteries, depress the range selector in either direction and observe that the needle rests on the zero check line that is just to the left of the scale. If it doesn't, use the adjusting screw to make it do so, while holding down the range selector. That's all there is to it. Good Luck

-- Robert A. Zeichner (razeichner@ameritech.net), July 25, 1999.

Thanks for the information Robert. Pat

-- pat j. krentz (krentz@cci-29palms.com), July 25, 1999.


You can also get the 1.3v batt. that the Luna Pro takes at Freestyle in L.A. Pat

-- pat j. krentz (krentz@cci-29palms.com), July 25, 1999.

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