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Re: Spot meter
I'd probably add to the variable by using digital (gowd forbid camera :>) to make the visual determination.....adjusting exposure on both sides of the spectrum. Shooting a candle is one thing, but having it reflect on someone's face or adding additional light (matching K degrees) to do so....just gets more convoluted. Some of us had this assignment from Vilmos Zsigmond, during one of his workshops....so this has some echo.
Les
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Re: Spot meter
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Re: Spot meter
If there's any consistency to it, the point is to get a digital camera. Thank you for participating.
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Re: Spot meter
gracias, es un buen punto usar el que da mejor detalle en las sombras.. la diferencia entre ambas es de 2/3, como ultimo recurso solo ajusto 1/3,
solo la prueba y error me dará algo de seguridad.
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Re: Spot meter
Quote:
Originally Posted by
Luis-F-S
Use el Digital! L
Which of the digitals do you recommend?
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Re: Spot meter
Ricardo,
Is there a camera-repair place that can check the calibration of your meters? It’s a pretty simple procedure with a proper calibration light source.
One thing to bear in mind when asking “which one is more accurate”: spectral responses of meters vary considerably. Pentax meters are quite broad, with response extending into the near infrared; others such as Minolta (now Kenko) were much narrower, corresponding (sorta kinda) to the 1931 CIE observer. Neither, of course, may correspond to the spectral response of film or an electronic sensor. Under ordinary conditions, depending on the color of the metered subject, I’ve seen 2–3 step differences between my Pentax meters (the digital is a Zone VI) and my Minolta Autometer IV. In an extreme case (a semiconductor photolithography room under yellow light), I once saw a five-step difference between my Pentax V and my Minolta Flashmeter III. I don’t know what the spectral response is for Sekonic meters.
Bottom line: “accuracy” is loosely defined at best. But for starters, try to get a proper calibration check. It may not be perfect, but it’s more reliable than most home-brew solutions.
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Re: Spot meter
jeff,
i totally agree, a camera repair shop is the right thing, the point is that where i live there are no analog camera repair shops, there is very little material for photometers. so i am looking for a home made solution that will give me an idea of which one is better calibrated. i have to do tomorrow with the lus of day, checks and see if the 2/3, are maintained in all values. i am looking for low and high areas. All agree that not all respond to the same illuminated subject with the same value. and that some photometers are calibrated for zones V or IV, and another subject as much as both are Pentax, both are different...
Calibara is a better choice than any homemade attempt.
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Re: Spot meter
Ricardo,
It’s been a while since I’ve been to a repair shop, so I’m not sure where I’d go for a meter calibration (San Francisco Bay Area) these days. The best I can suggest is to call a few places and ask (and ask what type of calibrator they have and see if they understand the calibration factor K). Meters aren’t really calibrated to “zones” (the calibration standards were aimed at everyman rather than Ansel). Pentax meters (analog and digital) used a K of 14 (1.3 if you work in cd/ft2); Minolta did the same. Sekonic use 12.5, which is closer to the most recent standard (ISO 2720:1974; yep, that old). Canon and Nikon did the same the last time I checked, though few people at either company even knew what I was talking about. Any of these is somewhat artificial, and most calibrators don’t exactly follow the standard, which calls for a filter to create a 4700 K light source; the calibrators I’ve seen use an unmodified CIE A illuminant (2856 K). But at least it was standard. You get your calibration from the instruments you have; they’re not the instruments you want or might wish to have at a later time.
I discuss calibration and its effect in some detail in https://www.largeformatphotography.i...-meter-cal.pdf (boy, was that a long time ago ...).
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Re: Spot meter
Since the last time I contributed to a light meter thread like this I got a Sekonic meter that allows one to calibrate it via the menus. That is, one does not need to take it apart to find trimmer pots. I have been using a known film (using its indicated ISO) as a standard. Works better than a 'standard candle' for me.
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Re: Spot meter
My advice is to use the meter that works best for you and then put the other meter away. Trying to get 2 meters to agree all of the time is like chasing unicorns. I had one meter calibrated and then I sort of set all my cameras and meters to somewhat agree with the calibrated one and then never bothered to check them again. That was about 40 years ago and everything seems to be still working fine.