Sekonic light meter - EV Function???

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My Sekonic light meter has an EV function but I can't figure out what it is for or how to use it? EV on my camera no problem - on the Sekonic - HUH??? Reading the instruction booklet does not help. I hope you Café members can give me an explanation.
 
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EV on the camera is sort of a word for "number of stops of change". We might compensate the exposure by say +1.3 EV step. It represents a known change amount.

EV in the light meter is different.

We can set our camera to a fast shutter and wide aperture, or to a slow shutter and narrow aperture.... giving same exposure, called equivalent exposure. There likely are combinations to give half a dozen such possible equivalent exposures, the same exposure. The name of that set of equivalent exposures is called an EV number... like maybe EV 10. It represents the set of numerical aperture/shutter combinations of all possible equivalent exposures in one certain set.

The system starts at f/1 1.0 second, called EV 0. That could represent f/1.4 at 2 seconds and f/2 at 4 seconds too, all possible equivalent exposures are called EV 0.

A stop brighter is f/1.4 and 1.0 second (or f/2 and 2 seconds) and that set is called EV 1. Etc.

Wikipedia likely has a better explanation:

http://en.wikipedia.org/wiki/Exposure_value

Study their chart briefly, and it should be clear. f/1 and 1 second is EV 0. Every adjacent square is 1 stop different...

BUT A ROW is all equivalent EV.

If metered, the meter is saying any combination on that metered row is correct, for the ISO you entered into the meter.


The tricky part: The overall concept is that these are camera settings.... the name for a set of equivalent exposure camera settings. The actual settings. It is NOT necessarily about any correct exposure. It is simply about the numerical camera settings. Which might be an exposure capability, but is not necessarily about a correct exposure. It does not matter what ISO is, or how bright or dim it is, or if our picture is under or over exposed, but EV is a name for a set of numerical camera settings giving equivalent exposure.

SO it is NOT about ISO 100 either, however, we do find uses that qualify to say "if at ISO 100, bright sunlight might be EV 15", but ISO is not implied in the EV definition. The same sunlight might be any EV with other ISO values.

However, the light meter does use your selected ISO value to meter an EV number, but it can be any ISO number.

EV is simply something that exists, but probably wont be very useful.

One use is that it can measure relative brightness. If looking for the place to set the house plant, you might find Spot A is 1.5 EV brighter than Spot B.
 
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Joined
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For one better example...

See page 430 of your D700 manual.

About chart center there, it says about metering range:

IF ISO 100 and f/1.4 lens, then 0-20 EV range.
(Spot metering is 2-20 EV range)


By specifying one ISO value, it does become a brightness range.

The Wikipedia EV chart shows you which range.... 0 EV to 20 EV.
 
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