User manual

is recommended for photographing architectural
subjects against a blue sky.
The A Fi lte r is a red filter and can be used only
with panchromatic materials. It is used where
strongest contrast effects are desired. Red and
yellow photograph almost as white, while blues and
greens are recorded as black.
FILTER FACTORS: The filter factor represents the
number of times the exposure must be increased if
a filter
is used. A filter having a factor of 2 requires
twice
the exposure necessary without it.
KODAK INFRARED FILM IR620
This film reaches into that portion of the spectrum
beyond the visible red. The most common use for
the Kodak Infrared Film is distant landscape
photography, though it is also very useful for
scientific, medical,
and criminological photography.
When a distant landscape is photographed on an
ordinary film, the distance often lacks detail on
account of the haze. This is because violet and blue
light, to which an ordinary film is sensitive, is
scattered by atmospheric haze. The longer wave
lengths of the visible light and particularly the
invisible infrared, however, are freely transmitted
by the haze. A photograph made on infrared film,
with a deep yellow or red filter over the lens to
absorb the violet and blue light, will often (depend-
ing on atmospheric conditions) show distant ob-
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