midway between black and white, all the other shades will be reproduced in
(1) Even if you don't have a gray card, try to find something in the
scene which you know should be about the same shade as a gray card. Take a
close-up reading of that one small part of the scene and use the result to
set your camera.
(2) Another way to determine a light reading is to use the palm of
your hand as a starting point. The average palm skin tone is about one stop
lighter than a gray card, so in a pinch, you can just place your hand in the
same lighting as the scene you are photographing and meter it as you would a
Then set your camera to give one stop more exposure than the
meter says and you're set. If you take a comparison reading of a gray card
and the palm of your hand (and remember what the difference is) you can
adapt the technique for your own use.
(3) To carry this a step further, white houses are about five times
as bright as middle gray.
In fact, almost anything painted white or
whitewashed is about 2-1/3 stops brighter than middle gray. So if you meter
a white painted wall and then give 2-1/3 stops more than the meter
indicates, then you will be pretty close to the right exposure. Most gray
cards are gray on one side and white on the other.
This white side is
exactly five times as bright as the gray side.
You can get a very good
exposure by metering the white side of the card and giving five times the
exposure the meter says. You can do this by opening the lens about 2-1/3
stops, or by adjusting the ISO setting on the meter to 1/5 what you would
use with a gray card.
This is particularly useful when taking a meter
reading in dim scenes when there isn't enough light to make a meter's needle
move. By using a white card, you can effectively extend the meter's usable
range by a factor of five.
f. You must take care, when metering small areas, to hold the meter
close enough to the area so that you are reading only the portion of the
scene you want. If you include areas that are lighter or darker than the
spot you wish to read, you'll get incorrect readings.
Also, be careful
about shading the meter's target with your body, your hand, or the meter
Cameras with built-in meters are highly sophisticated, but they are
still basically reflected light meters, and are susceptible to the same
failings hand-held meters are.
Many through-the-lens meters are center
weighted, which means the meter pays more attention to the brightness in the
center of the scene than to its edges. This is useful in certain lighting
conditions, but doesn't do much good if you are trying to meter a darker or
lighter than average scene which you don't want to look middle gray. Even
the most sophisticated camera meter will try to make a white house or black
cat the same shade of gray, just as the hand-held meter will.
camera meter can be manipulated the same way a hand-held meter can, and all
the tips in this lesson can be used with your camera just as effectively as
well. Of course, once you know how to use a calculator dial, you might find
it so useful you may regret that cameras with built-in meters don't have