Datasheet

15
■ BASIC DIGITAL CAPTURE WORKFLOW
A spot meter can read directly from the mid-gray patch (third from the right
on the bottom of the ColorChecker); open up
1
⁄
3
stop to get the base exposure. If you
don’t have a spot meter, use an incident meter and take a reading from the subject
position, pointing the white dome at the main light source (Figure 1.10). The ideal
way to take exposure readings, at least for the test, is to use a hand-held light meter.
A hand-held meter is better than relying on the camera meter for a number of reasons.
If you have to use your in-camera meter, get yourself a large reference card like the
Lastolite EZYBalance (Figure 1.11). You can move in close enough to fill the frame
with the large gray field. Remember to open up
1
⁄
3
stop from any reading off any 18
percent gray reference.
Figure 1.10 Point the incident meter “dome” at the light source.
Once you’ve determined your starting exposure, you will shoot additional
exposures, incrementing the f-stop value by
1
⁄
3
f-stop using the manual controls on
your camera. Shoot two stops on either side of the starting exposure and keep track
of the exposures as you go along. I find it convenient to indicate the exposure change on
the target itself by writing on a paper attached to the target. I write down the differ-
ence in exposure as a change in ISO. In other words, if I stop down one-third from the
ISO 100 reading, I write 125:
2
⁄
3
= 160, 1 stop = 200, and so on. The beginning of the
sequence would go: 100, 80, 64, 50.
Whatever you do, don’t base your exposure off the appearance of the LCD
on the back of the camera! (See Figure 1.12.) Not only do most viewing conditions
prohibit accuracy, but the LCD will only show you how the camera would generate a
JPEG—it can’t show you what is in the RAW file. Typically, the histogram is only a
composite histogram—and even when you can display separate RGB histograms, they
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