
You can actually make your own incident
meter from a reflective meter. Here’s how: set-up a grey-card, take a
reflective meter reading off its surface, (see Image [3]), remember this
reading, then orientate the back of the meter towards the grey-card so
that its receptor is pointing directly at the light source you want to
read (see Image [4]). If you should happen to take a reading at this
time, it will read much higher than the reflective reading off the
greycard. Now hold a piece of white paper tightly against the meter’s
receptor so that the light has to pass through the paper to hit the
chip, (see Image [5]). Take another meter reading with the paper-covered
receptor pointing directly at the light source. If the reading still
does not match the reflective reading then fold the paper over and try
again. Fold the
paper
over as many times as necessary until you have added enough density over
the receptor that the two readings are equal. Now the paper is absorbing
as much light as is the grey pigment coating the grey-card and it is
this fact that makes it possible for an incident reading of the light
striking an area to read the same as a reflective reading off a
grey-card, only without a grey-card - what a convenience! Better yet,
forget the white paper, the white incident dome that comes with your
light meter does the same thing only is a more convenient accessory than
is white paper, so by all means use it!
And now a handy incident metering trick:
When you are metering with the white incident dome attached to your
meter, look at the dome, you will see
a reflection on its surface from the source you are pointing it at. If
you are using multiple sources such as main, fill, separation, and hair
light, look for reflections on the dome from these lights to see which
are contributing to the exposure. I typically like to read my sources
separately to see what each light’s value is, then I know exactly what
the ratio between my lights are. A hair light for instance, can
influence the reading of my main-light (see Image [6]), looking at the
dome guides my hand to the best position to block that separation light
from the dome and from my reading (see Image [7]). Many lighting experts
use flat incident disks for this purpose, however, I find flat disks are
very angle sensitive and so require more care than I want to give during
the heat of the battle. Many ask me, “Well, doesn’t your hand reflect
some light back onto the dome as well thus inf
luencing
the reading?” to which I answer, “Yes, but not enough to matter.”

Photo Quote: Photography, as a powerful medium of expression and communications, offers an infinite variety of perception, interpretation and execution.- Ansel Adams