Basic Photography Course

is an electrical-mechanical device that can only provide

information for which it is designed. You are responsible
for translating this information into useful exposure
data.

Light meters are calibrated to see one shade

only-middle gray. This means the information that the
meter provides, no matter how much light is falling on
the subject or what the reflection characteristics are,
reads the subject the same as though it were middle or

neutral gray (18-percent gray). Theoretically, if you take
a reflected-exposure meter reading from an 18-percent
gray card and expose your film according to the reading,
the result should be a picture that matches the tone of
the gray card exactly; however, when you take a light
meter reading of a white or black object, the light meter
still reads the objects as though they were 18-percent
gray.

When you take a photograph that includes a gray,

white, and black card, you will see how, depending on
where you take the light meter readings, they affect your
photograph; for example, when you take the light meter

reading from the black card, the final picture reproduces
the black as middle gray, and the gray and white cards
as white. When you take the reflected-light meter
reading from the white card, just the opposite occurs. In

your final picture, the white card reproduces as middle
gray, and the gray and black cards reproduce as black.

This example demonstrates overexposure and

underexposure. When the reading was taken from the
black card, the meter raised the black tone to middle
gray, and the gray card tone was also raised so it
reproduced as white. Thus both the black and gray cards

were overexposed The opposite occurred when the
exposure was based on the reading from the white card.
The white tone was lowered to middle gray and the gray
card tone to black, resulting from underexposure. Only
a light meter reading taken from the gray card allows all
three cards to be imaged at their true tone.

A more practical example on the way a light meter

reads 18-percent gray is illustrated in the following
example. Suppose you are going to photograph a ship

alongside a pier. Bright sunlight is striking the ship from

the side, causing part of the ship to be in shadow. This
creates a brightness difference between the highlight

area and the shadow area. Both highlight and shadow
areas are equal in size and importance. When you get
close to the ship and take a reflected meter reading of
the highlight area alone, you expect the finished
photograph, like the white card in the above example, to
be middle gray. When you stop down the aperture to the
recommended exposure of the meter, you are also

reducing the amount of exposure from the shadow area.
This results in a loss of detail in the shadow area of the
ship, because it is underexposed. The opposite effect
occurs when you take a meter reading from the shadow
area. In this case, the shadow tones are raised to middle
gray and have detail, but the highlights are overexposed
and completely "washed out."

If, however, there was an area in this scene whose

tone was midway between the highlight and shadow
areas, you could use it to take your light meter reading

(like the gray card was used in the previous example).
In this example, assume there is no tone midway
between the two extremes. You can still get an accurate
light meter reading of the entire ship. Since the highlight
and shadow areas are of equal size, the average light
meter reading you get will represent a tone that is

midway between the two extremes.

REFLECTED LIGHT METER READING
VARIATIONS

There are variations of light meter readings used to

provide accurate light meter readings of different types
of scenes. These methods are as follows: the integrated,
or average, method, the brightness range method, the

darkest object method, the brightest object method, the
substitution method, and the bracketing method.

Integrated, or Average, Method

The technique of making reflected-light meter

readings from the camera position is called the
integrated, or average, method. This method was used
and explained in the examples above. This method is

accurate for the majority of photographs taken.

The integrated, or average, method of measuring

reflected light is acceptable for scenes that consist of
approximately equal portions of light and dark areas;
however, when a scene is composed of either
predominately light or dark areas, the meter reading may
not be accurate.

The reason for these inaccurate meter readings can

be more easily understood by using an example of
photographing a checkerboard with alternating
black-and-white squares. When the meter is held at a
distance to include the entire board, the reflected light
from both the black and the white squares influence the

meter, so an average reading results. The light measured
from this position is the integrated sum of both the white
and the black squares, as though the checkerboard were
one gray tone. The light meter reading from this point
should produce an acceptable image.

4-23

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Basic Photography Course

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DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> is an electrical-mechanical device that can only provide information for which it is designed. You are responsible for translating this information into useful exposure data. Light meters are calibrated to see one shade only-middle gray. This means the information that the meter provides, no matter how much light is falling on the subject or what the reflection characteristics are, reads the subject the same as though it were middle or neutral gray (18-percent gray). Theoretically, if you take a reflected-exposure meter reading from an 18-percent gray card and expose your film according to the reading, the result should be a picture that matches the tone of the gray card exactly; however, when you take a light meter reading of a white or black object, the light meter still reads the objects as though they were 18-percent gray. When you take a photograph that includes a gray, white, and black card, you will see how, depending on where you take the light meter readings, they affect your photograph; for example, when you take the light meter reading from the black card, the final picture reproduces the black as middle gray, and the gray and white cards as white. When you take the reflected-light meter reading from the white card, just the opposite occurs. In your final picture, the white card reproduces as middle gray, and the gray and black cards reproduce as black. This example demonstrates overexposure and underexposure. When the reading was taken from the black card, the meter raised the black tone to middle gray, and the gray card tone was also raised so it reproduced as white. Thus both the black and gray cards were overexposed The opposite occurred when the exposure was based on the reading from the white card. The white tone was lowered to middle gray and the gray card tone to black, resulting from underexposure. Only a light meter reading taken from the gray card allows all three cards to be imaged at their true tone. A more practical example on the way a light meter reads 18-percent gray is illustrated in the following example. Suppose you are going to photograph a ship alongside a pier. Bright sunlight is striking the ship from the side, causing part of the ship to be in shadow. This creates a brightness difference between the highlight area and the shadow area. Both highlight and shadow areas are equal in size and importance. When you get close to the ship and take a reflected meter reading of the highlight area alone, you expect the finished photograph, like the white card in the above example, to be middle gray. When you stop down the aperture to the recommended exposure of the meter, you are also reducing the amount of exposure from the shadow area. This results in a loss of detail in the shadow area of the ship, because it is underexposed. The opposite effect occurs when you take a meter reading from the shadow area. In this case, the shadow tones are raised to middle gray and have detail, but the highlights are overexposed and completely "washed out." If, however, there was an area in this scene whose tone was midway between the highlight and shadow areas, you could use it to take your light meter reading (like the gray card was used in the previous example). In this example, assume there is no tone midway between the two extremes. You can still get an accurate light meter reading of the entire ship. Since the highlight and shadow areas are of equal size, the average light meter reading you get will represent a tone that is midway between the two extremes. REFLECTED LIGHT METER READING VARIATIONS There are variations of light meter readings used to provide accurate light meter readings of different types of scenes. These methods are as follows: the integrated, or average, method, the brightness range method, the darkest object method, the brightest object method, the substitution method, and the bracketing method. Integrated, or Average, Method The technique of making reflected-light meter readings from the camera position is called the integrated, or average, method. This method was used and explained in the examples above. This method is accurate for the majority of photographs taken. The integrated, or average, method of measuring reflected light is acceptable for scenes that consist of approximately equal portions of light and dark areas; however, when a scene is composed of either predominately light or dark areas, the meter reading may not be accurate. The reason for these inaccurate meter readings can be more easily understood by using an example of photographing a checkerboard with alternating black-and-white squares. When the meter is held at a distance to include the entire board, the reflected light from both the black and the white squares influence the meter, so an average reading results. The light measured from this position is the integrated sum of both the white and the black squares, as though the checkerboard were one gray tone. The light meter reading from this point should produce an acceptable image. 4-23 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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