<p><b>Reflected Light Readings for Film and Digital Images</b></p><p>In
order to correctly expose your film or digital CCD there are two
variables that must be identified: average reflectance and average
light. Unless you have some good reason to meter for other than these
two averages, stick meticulously to the method outlined below.</p><p>This
article deals with reflected light readings. This is the type of light
reading taken with an in camera light meter or a hand held meter which
is pointed toward the subject. This article does not deal with incident
light readings which are a measure of the light falling on the subject.</p><p><b>Average Reflectance</b></p><p>A
white painted wall, snow or the ocean reflect most of the light falling
on them. A burnt tree, a black fireplace or a coal mine reflect little
of the light falling on them.A mid tone falls halfway between these
extremes and reflects 18% of the light falling on it. The ISO rating of
film or a digital CCD is set so this mid tone is exposed as a mid tone.</p><p><b>Identify a Mid Tone</b></p><p>Identify
a mid tone for average reflectance and meter off that. Look for some
green grass or foliage, mid tone rocks or bare dirt, weathered timber
or whatever you can find that is somewhere in the middle between dull
black and shiny white. If you are unable to escape a predominance of
one extreme or the other in your framed image, then find an area to
meter else where.</p><p>If need be, point the meter toward yourself and
meter your clothes or else take your coat off, throw it on the ground
and meter that.</p><p>Sand at the beach, or the palm of your hand are
about one stop too bright. These can be used to meter off but you must
compensate and the liklihood of a mistake is introduced.</p><p><b>Average Light</b></p><p>Average
light is half way between light and shadow. If it's overcast there
isn't so much difference between the two extremities as when it's sunny
but you still should take a reading of the average light.</p><p><b>Identify Average Light</b></p><p>If
you are metering off some trees and scrub in full sun you'll probably
find that the scene makes it's own shadows within the foliage. Be
careful because the amount of sun and shadow can be confusing.</p><p>If
metering a tree, aim your meter such that you read off half sun and
half shadow on the tree trunk, then if need be, move around the tree to
your chosen photo spot to capture the image. On a rough barked tree
such as a pine tree, make sure that the texture of the bark on the
sunny part has not created half shadow.</p><p>If metering a building,
meter off a corner so you get one wall in the sun and the adjacent wall
in the building's own shadow. Alternatively, meter half the sunlit
building and half the shadow on the ground.</p><p>When photographing
the landscape I always take my own shadow with me. Yes, as long as the
sun is shining my shadow will be there with me. I crouch down and meter
off the ground and point the meter so half of it reads my shadow and
the other half reads the sunny area. That's my reading till the light
changes. If I have any doubts about the average reading, I take a
reading from the shadow area and another from the sunny area, then see
if my average light reading is in the middle.</p><p><b>Metering Indoors</b></p><p>When
photographing indoors by window light, be sure to meter for the average
of the subtle difference between light and shadow. This difused,
directional light, according to my view of the world, is the most
attractive and useful light for photography. Although the level is low,
the quality is high. Strive to meter it acurately.</p><br clear="all"><br>-- <br>Alexander Malich