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false_Aesthetic
23-Apr-2012, 14:09
Hey,

I know that analog meters need calibration sometimes. What about digital ones (e.g. L-508 or whatever)?

Thanks

vinny
23-Apr-2012, 14:43
yes. the sekonics are known (in the film industry) for often being "off" compared to other meters (spectra).

Heroique
23-Apr-2012, 14:50
Walk-in camera shops commonly offer free on-the-spot examinations.

What’s fun is to get an opinion from two different shops.

Two technicians told me my Pentax digital overexposes by 1/3 stop.

So I believe it does – and ignore the problem.

Marc B.
23-Apr-2012, 14:54
Yes, even digital light meters do need/require calibration from time-to-time.
You may wish to contact the experts at QLM. Lucky you...they're in your own back yard.

Quality Light Metric Co.
PH# (323) 467-2265
7095 Hollywood Blvd Ste 550.
Los Angeles, CA 90028

Leigh
23-Apr-2012, 15:05
The sensor and measuring circuitry are the same regardless of whether the display is analog or digital.

So periodic calibration might be advisable. But these devices are very stable, so I wouldn't obsess over it.

- Leigh

Drew Wiley
23-Apr-2012, 16:06
I believe Quality Light Metric only does Pentax. But you could call him. Anyway, he does an
excellent job and matches to a standard. And yes, these meters can drift. I happen to keep a brand new one tucked away just to check my other meters, which seem to need
a correction about every decade. It can be important with chrome films or other fussy
situations. And you have to compare readings clear across the scale, not just with a gray
card (which are never really 18% gray anyway). I can't imagine any camera shop being
able to do this correctly, unless they were just comparing your old meter to their new one.

vinny
23-Apr-2012, 16:30
I believe Quality Light Metric only does Pentax. But you could call him. Anyway, he does an
excellent job and matches to a standard. And yes, these meters can drift. I happen to keep a brand new one tucked away just to check my other meters, which seem to need
a correction about every decade. It can be important with chrome films or other fussy
situations. And you have to compare readings clear across the scale, not just with a gray
card (which are never really 18% gray anyway). I can't imagine any camera shop being
able to do this correctly, unless they were just comparing your old meter to their new one.

He does other brands as well. I had a minolta f worked on there.

Wally
27-Apr-2012, 06:59
... And you have to compare readings clear across the scale, not just with a gray
card (which are never really 18% gray anyway). ... That would be true if used with a fixed-brightness light source a fixed distance from the card.

To use the same gray card to test different EVs, change the illumination (change the lights brightness or move it closer to or farther from the card).

Leigh
27-Apr-2012, 09:58
And you have to compare readings clear across the scale, not just with a gray
card (which are never really 18% gray anyway).
Not true.

Any modern (electronic) light meter can be checked at a single point,
with confidence that all readings within its specified range will meet tolerance.

Sensor response is linearized by design.

And BTW... 18% gray cards do have that reflectance when used properly.

I'm constantly amazed/amused by the self-styled experts who know more than the manufacturers.

- Leigh