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Joseph O'Neil
17-Mar-2008, 10:20
Dumb question time. I just took delivery of a used Pentax spot meter - analog. Excellent shape. I already have one, and the price was right to have a second one as backup.

A few years ago my first spot meter took a bath in a river, but it was rebuilt and re-calibrated by Pentax, and it's never given me any trouble since. Comparing the two meters side by side, and they appear to be identical models from anything i can see, the "new" meter is exactly one full stop faster than my old meter. So easy enough to adjust for, but I was wondering about changing the calibration myself.

On the front of these analog meters there is a slotted screw you use for adjustments, but I've never touched mine as I've never had too. This is the "zero" adjust. On my "old" meter, the one calibrated by the factory rebuild, the needle stops exactly on the "19" mark. On my "new" meter, the needle stops exactly in the middle of the black dot just past the "19" on the scope.

So while I could adjust the new meter to match my old one, but I am wondering if I wouldn't bugger things up and maybe best to leave things alone, just label the new meter so I know the difference.

Other dumb question -is the "19" the proper mark, or the black dot.
:)
thanks
joe

jetcode
17-Mar-2008, 10:56
I remember hearing a story from a great solo guitarist who carried 3 tuners on tour. The problem was that two of the tuners read the same the 3rd one didn't. Which tuner was right?

It's going to sound crazy but I would send them both in to be calibrated or at least the latest acquisition.

Ted Harris
17-Mar-2008, 11:00
Send to Richard Ritter www.lg4mat.net. Richard is an expert on Pentax meters.

CG
17-Mar-2008, 11:13
The name I keep seeing for meter repair and calibration is:

George Milton at

Quality Light Metric Co.
7095 Hollywood Blvd. No. 550
Hollywood
CA 90028

USA

Tel: 323 467 2265
Fax: 323 467 2284

I haven't had to use them yet, but they seem to have a host of happy customers.

C

ic-racer
17-Mar-2008, 11:18
The 'Zero Adjust' does not calibrate the meter. Per the manual, this should be adjusted so the needle is on the dot, not the '19.'

If they are still not reading the same, check the batteries. If you want them to read the same, one will have to be re-calibrated.

Like it was pointed out : Confucius say, "Man with one watch know the time, man with two watches does not!"

I have about 12 light meters, I'd go crazy trying to get them to all read the same. I just make adjustments to the exposure index for the equipment in use.

Scott Kathe
17-Mar-2008, 12:02
The name I keep seeing for meter repair and calibration is:

George Milton at

Quality Light Metric Co.
7095 Hollywood Blvd. No. 550
Hollywood
CA 90028

USA

Tel: 323 467 2265
Fax: 323 467 2284

I haven't had to use them yet, but they seem to have a host of happy customers.

C

Joe,

I have used George Milton, first with a Luna-Pro SBC and then a Soligor Analog Spotmeter. He calibrated and shipped the meters back the same day he received them. They seem to work great and agree with each other! That being said if all I had was the spot meter I give Richard Ritter a try.

Scott

David Karp
17-Mar-2008, 12:16
I third the recommendation of Quality Light Metric. I have two Pentax Spotmeters, one analog, one digital. They were calibrated by QLM on separate occasions and the readings from each match.

jetcode
17-Mar-2008, 12:33
I third the recommendation of Quality Light Metric. I have two Pentax Spotmeters, one analog, one digital. They were calibrated by QLM on separate occasions and the readongs from each match.

I have to imagine this company works with a lot Hollywood cinematographers. Shipping on the west coast will be less expensive too.

RichardRitter
17-Mar-2008, 12:54
The black dot is the null setting for the meter. Best thing to do is run a Zone one test and an zone eight test. Set the meter to the test results and go photographing.


Since both meters read one stop off across the full range of the scale. I would mark the meter that is off and not bother to send it any where. Keep it as a back up. Sometimes trying to get two meters to read alike and sending only one meter to be calibrated is not a good idea.

Tom Schaefer
17-Mar-2008, 14:20
Richard
Are you still able to zone calibrate a
Pentax Meter. I tried calumet but they are
not doing it right now.
thanks
Tom S

Patrik Roseen
17-Mar-2008, 14:33
My experience with light meters (see thread 'Light meters adding to confusion') is that the difference between one meter and another might not be linear, i.e there could be one stop difference in bright light but another difference in low light. This might not be so important for B&W but it sure is for color slides.

Eric Woodbury
17-Mar-2008, 16:34
If you want them to match, send them both in. If you are shooting BW, don't worry about it. Put a note on one and carry as a spare and calibrate your process to the one you use all the time.

Steve Feldman
17-Mar-2008, 17:00
I have a Minolta M Spot Meter and 2 Gossen Luna Pro F's. It was a very simple matter to "zero" in the Luna Pro's to match each other (1/3 stop off) and then make the Minolta Spot match the Luna Pro's (less than a 1/3 off). - Life is good.

Feldman's corrolary to Confucius says, "Man with one watch knows the time, man with two watches does not know time. Man with one non-working watch knows the correct time - twice a day."

Eric Woodbury
17-Mar-2008, 20:55
I don't think the Pentax meter is that simple to adjust. It should have an offset (zero), a gain adjust (the high point) and then it should have an adjust for the middle since it can sag or crown. The early Pentaxs especially, can be non-linear, that is two points on a slightly curved line are right, while the rest of the EV readings are off by varying amounts.

I know it's hard, but if it works, use it and don't worry about being cal'd.

RichardRitter
18-Mar-2008, 06:05
Richard
Are you still able to zone calibrate a
Pentax Meter. I tried calumet but they are
not doing it right now.
thanks
Tom S

Yes I keep a supply of parts on hand so I can also repair the meters.
Calibration with shipping is around $82 with a turn around of about 2 to 5 days.

akalai
18-Mar-2008, 20:22
Another vote for George Milton at Quality Light Metric, Hollywood.

I have sent several items to George and he has always been a real pleasure to deal with and delivered a high level of workmanship that clearly shows he is a great technician.

EuGene Smith
21-Apr-2008, 21:24
Richard:

Do you work on only Pentax spot meters, or do you do other brands as well?