Evening star., 1951-09-16
BY Alexander J. Wedderburn
Cvrotor Of Photography
The Smithsonian institution

by AIeXonQeI }. VSuuStUuTu
cvrutor Of Photography
The Smithsonian Institution
It's time for another addition
to our glossary of Photographic
terms. A working knowledge of
the meaning of words and phrases
commonly used among photogra-
pliers will help you to understand
articles and lectures on the sub
ject with the ultimate result that
your picture-taking will steadily
improve.
An "air brush" is a spraying tool
used to apply liquid colors to
Photographic prints. An entire
unwanted background can be
quickly blocked out with the air
brush and tone values changed at
will. The professional air brush
is too expensive an item for anna
teur use but an artists mouth
operated brush or atomizer can
be an effective substitute.
In portrait photography we
often hear the term character
lines" These lines, which be-
come more noticeable as we grow
older. have a great deal to do with
the natural expressions by which
we are recognized by our friends
and acquaintances. Without these
character lines, faces would ap-
pear as a blank mask-an effect
often seen in portraits where an
overenthusiaStic amateur retouch-
er has removed most or all of
these lines in an attempt to make
the subject appear younger. Char
acter lines may be softened but
should never be removed entirely.
Facial blemishes and fine wrinkles
are not considered in this cate
CORY and may be deleted II
desirable.
Composite Pictures.
A composite" picture is one
which is made from two or more
prints or negatives. A simple COM
posite picture may be made from
two negatives by printing part Of
the picture while shielding part
of the printing paper with a
mask. Then the printed portion is
protected by a mask while the
second portion is printed in from
the other negative. An easier
method for the beginner would
be a combination of two or more
prints. Portions of other prints
are cut out and pasted on a print
which is then copied with the
camera. The master negative is
then used to make the final print.
Whichever method is used great
care must be taken to prevent
the junctures from showing. When
negatives are used the masks
must be kept in constant motion
during the printing to insure a
perfect blending at the point
or points where the several parts
are Joined. If you prefer the other
method use a razor blade or other
very sharp blade when making
the cut outs and wipe away all
traces Of the glue. paste. or other
material used to bond the parts
together.
Concentrated solutions" are
often used by the photographer
who wishes to save time in mixing
chemicals for processing films
and prints. A concentrated Solu-
tion is one which is much stronger
than will be needed for the actual
processing. When needed, a por-
ton is diluted with water to
bring it to the desired strength.
The concentrated solution should
never be used as is but diluted
with water according to the rec
commended formula.
A credit line" is the name of
the photographer or agency that
takes or sells the picture. If you
plan to make your living or sup
plement it by selling pictures for
publication, be sure that each
print carries your name with the
request that a credit line be used
The credit line will become your
trade mark and draw the atten-
ton of those who are in need
Of the services Of a good photog-
rapher.
Density of Negatives.
Density" is another commonly
used Photographic term. 1t refers
to the degree of opacity of the
negative. When you hear a
camera fan speak Of a dense mega
tive he means that heavy silver
deposit has been retained by the
negative and will require a longer
exposure when making the print.
A thin negative is one which has
less than the normal deposit of
silver and demands consequently
a shorter exposure in printing.
A "diapositive" is positive
image formed on a transparent
Photographic printing material
such as a slide, glass plate, or film.
DlapoS1tlveS are used Tor project
ing as lantern slides or film strips.
Other photographers use them as
one of the steps in the paper mega
tive process. Large diapositiveS
can also be backlighted in a box or
used in the making Of lamp
shades.
An enlarged negative" which
Is sometimes desirable, can be
made in one of two ways. The
first step is to make diapositive.
This can be made by direct con-
tact printing. If you do it this
way the diapositive is then placed
in the enlarger and the print
made on another sheet of negative