Basic Photography Course

the projected image on the focusing paper in the easel
and estimate the amount of exposure time you think the
print requires. From experience, you estimate the
correct exposure time to be about 15 seconds. Because
your estimate may be incorrect, a logical procedure is to
expose a test strip in four sections.

To make the actual test strip, you must do the

following:

1. Place one test strip on the easel in a position to

sample the highlights, midtones, and shadows.

2. Cover three quarters of the strip with opaque

paper or cardboard and expose the uncovered section for
5 seconds.

3. Move the cardboard to cover one half of the strip

and give another 5 seconds of exposure.

4. Again move the cardboard-this time to expose

three quarters of the strip-and provide 5 seconds of
exposure.

5. Now uncover the entire strip and expose it for

another 5 seconds. This produces a strip with exposures
of 5, 10, 15, and 20 seconds.

6. Process the test strip the same as contact prints.

7. Examine the processed test strip under white

light and select the segment representing the exposure
that gave the best results. If a time between two sections
gives the best result, make another test at the estimated
time. When you have selected the exposure, you are
ready to make a full-size print-if the contrast is correct.
If not, change filters and make another test strip.

The primary purpose for a test print is to determine

the correct exposure, but it can also help you determine
the correct contrast or printing filter to use. When the
test print is too contrasty or too flat, make another test
print with a higher or lower number of contrast printing
filter.

When printing, contrast (the difference in tonal

value between the highlights and shadows) is as
important for you to determine as is the correct
exposure. Almost all Navy imaging facilities use
variable contrast printing papers. To control contrast
with this type of paper, you must use variable contrast
printing filters.

Unlike film, increasing the development time of

paper does not increase the contrast significantly. In fact,
when paper development is carried out much beyond the
recommended time, contrast can actually decrease due
to fogging. Likewise, short development times should
not be used in an attempt to get lower contrast. The result

Table 11-2.Multigrade Filter Selection Guide

Filter Number

Use

Normal prints from very contrasty
negatives. Produces very flat

prints from normal or low-contrast
negatives.

Normal prints from normal
negatives, flat prints from low-

contrast negatives, and contrasty
prints from contrasty negatives.

Normal prints from low-contrast
negatives, and contrasty prints
from normal or high-contrast
negatives.

Normal prints from very low-

contrast negatives, and very
contrasty prints from normal

negatives.

of short paper development times is usually a print that
is not fully developed, and the print has poor tone quality
and a "muddy" appearance.

Variable contrast printing filters are the only

practical way of altering print contrast with variable
contrast papers. Variable contrast papers have
orthochromatic sensitivity. The blue light-sensitive part
of the emulsion controls high contrast, and the green
light-sensitive part controls low contrast. By using the
proper variable contrast filter between the light source
and the paper, you can control the contrast. Variable
contrast filters range from yellow (low contrast) through
deep magenta (high contrast).

When making test strips to determine correct

exposure, you also need to determine the contrast. You
do this by examining the shadow area of the test strip
that has the correct highlight exposure. When the
shadow area of this test is too light, the test does not have
enough contrast. When the test does not have enough
contrast, a higher number filter is required. When the
shadow area is too dark, the test has too much contrast
and a lower number filter is required.

Table 11-2 is based on using Ilford Multigrade

filters and Ilford Multigrade papers. Ilford Multigrade
filters are available in the following 12 grades: 00, 0,

11-13

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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 -> the projected image on the focusing paper in the easel and estimate the amount of exposure time you think the print requires. From experience, you estimate the correct exposure time to be about 15 seconds. Because your estimate may be incorrect, a logical procedure is to expose a test strip in four sections. To make the actual test strip, you must do the following: 1. Place one test strip on the easel in a position to sample the highlights, midtones, and shadows. 2. Cover three quarters of the strip with opaque paper or cardboard and expose the uncovered section for 5 seconds. 3. Move the cardboard to cover one half of the strip and give another 5 seconds of exposure. 4. Again move the cardboard-this time to expose three quarters of the strip-and provide 5 seconds of exposure. 5. Now uncover the entire strip and expose it for another 5 seconds. This produces a strip with exposures of 5, 10, 15, and 20 seconds. 6. Process the test strip the same as contact prints. 7. Examine the processed test strip under white light and select the segment representing the exposure that gave the best results. If a time between two sections gives the best result, make another test at the estimated time. When you have selected the exposure, you are ready to make a full-size print-if the contrast is correct. If not, change filters and make another test strip. The primary purpose for a test print is to determine the correct exposure, but it can also help you determine the correct contrast or printing filter to use. When the test print is too contrasty or too flat, make another test print with a higher or lower number of contrast printing filter. When printing, contrast (the difference in tonal value between the highlights and shadows) is as important for you to determine as is the correct exposure. Almost all Navy imaging facilities use variable contrast printing papers. To control contrast with this type of paper, you must use variable contrast printing filters. Unlike film, increasing the development time of paper does not increase the contrast significantly. In fact, when paper development is carried out much beyond the recommended time, contrast can actually decrease due to fogging. Likewise, short development times should not be used in an attempt to get lower contrast. The result Table 11-2.Multigrade Filter Selection Guide Filter Number Use 00 Normal prints from very contrasty negatives. Produces very flat prints from normal or low-contrast negatives. 2 Normal prints from normal negatives, flat prints from low- contrast negatives, and contrasty prints from contrasty negatives. 4 Normal prints from low-contrast negatives, and contrasty prints from normal or high-contrast negatives. 5 Normal prints from very low- contrast negatives, and very contrasty prints from normal negatives. of short paper development times is usually a print that is not fully developed, and the print has poor tone quality and a "muddy" appearance. Variable contrast printing filters are the only practical way of altering print contrast with variable contrast papers. Variable contrast papers have orthochromatic sensitivity. The blue light-sensitive part of the emulsion controls high contrast, and the green light-sensitive part controls low contrast. By using the proper variable contrast filter between the light source and the paper, you can control the contrast. Variable contrast filters range from yellow (low contrast) through deep magenta (high contrast). When making test strips to determine correct exposure, you also need to determine the contrast. You do this by examining the shadow area of the test strip that has the correct highlight exposure. When the shadow area of this test is too light, the test does not have enough contrast. When the test does not have enough contrast, a higher number filter is required. When the shadow area is too dark, the test has too much contrast and a lower number filter is required. Table 11-2 is based on using Ilford Multigrade filters and Ilford Multigrade papers. Ilford Multigrade filters are available in the following 12 grades: 00, 0, 11-13 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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