needing the meter after a while. This is because the same number pops up for each subject each time. LVs eliminate the confusing issues of film speeds and f/stops that hide these simple truths when using SLRs or other light meters:

LV18 and above: Bright reflection off a sunlit object, including reflections off the sea LV17 White object in full sunlight

LV16 Light gray object or skin in full sunlight

LV15 Gray card in full sunlight; typical exposure for ugly front-lit noon daylight photos

LV14 Typical light level for side-lit daylight shots in good afternoon light LV13 Typical shadow cast in a daylight scene; cloudy bright days

LV12 California bright overcast LV11

LV10 Dark, dreary overcast day in Boston, London or Paris LV 9

LV 8

LV 7 Typical indoors; light outdoors about 10 minutes after sunset LV 6

LV 5

LV 4

LV 3 Brightly lit night street scenes LV 2 Typical night street scenes LV 1 Dark scenes outdoors at night

LV 0 LV Zero is defined as the light level that requires a 1 second exposure at f/1 with ISO/ASA100 speed film.

LV-1

LV-2

LV-3

LV-4

LV-5 Scene lit by the full moon

LV-15 Scene lit only by starlight. I have loaded sheet film in light this dark, so don't expect to photograph it or meter it.

Some light meters use a similar scale, but shifted by a constant amount. For instance, the Gossen Luna-Pro uses a scale that reads 5 units higher, or reads 20 in full sun. It's still the same concept, and even those meters calculate the same Exposure Values, or EV, once you set your film speed. That brings us to:

EV, or Exposure Value

Exposure Value, or EV, varies from LV, or Light Value, depending on your film speed.

EV = LV at ISO 100

With ISO/ASA 100 speed film you expose with an Exposure Value (EV) equal to the Light Value (LV).

Easy, eh? Your meter will do this for you, but you can do it in your head, too, if you forget your meter. Here's how:

© 2007 KenRockwell.com

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