Advanced Photography Course

might need two, three, or four pictures to show the

different sides of a building; or you might make a near
and a distant view of the pinpoint target--one to show
detail and the other to show location. You can also make
more than one shot to produce one large, detailed
picture of a pinpoint target. In this case, three or four
shots having a 60-percent overlap are made. For
example, you may need three overlapping exposures to
give a large, detailed view of both ends and the middle
of a bridge. When the number of overlapped exposures
is small, say four or less, either vertical or oblique
photographs, the total composition may be called a
pinpoint aerial photograph, but technically, it would be
either a strip or a mosaic.

STRIP PHOTOGRAPHY

A strip is a series of overlapping exposures matched

together to form one long picture. A strip is used when
your assignment calls for photographing long, narrow
targets, such as railroads, highways, coastlines, rivers,
and mountain ridges. You may hold the camera at any
angle to make a strip; however, exposures made with
the camera pointing straight down from the aircraft join

together better and have the most consistent scale. A

strip comprised of oblique views is called a
PANORAMIC.

One long, continuous picture, made from a number

of photographs, requires the images to be matched
carefully so one picture ends where the next begins.
Because the camera is in a different position for each
exposure, a perfect match is impossible. But, by
overlapping exposures and using only the central area
of each picture, you can obtain a near-perfect result.

Once a strip is started, photographing it is a

mechanical job because the aircraft flies at a constant
speed and at a constant altitude. You should not alter

the camera angle while exposing a strip, and you should
make the exposures at regular intervals. Thus the
longer the strip, the more an automatic camera system
is preferred. The camera-to-scene distance must remain
constant while you are making the strip. The smallest
change in distance changes the image size and makes
matching adjacent exposures extremely difficult, if not
impossible.

MOSAIC PHOTOGRAPHY

Large land areas are photographed in strips that

overlap sideways. The strips are pieced together to

form one large composite picture, called a MOSAIC.
When photographing for mosaic purposes, you should
keep the camera the same distance from the scene

throughout the photographing evolution. Mosaics are
usually produced from vertical photographs made by

aircraft with an automatic camera system.

STEREO PHOTOGRAPHY

Two pictures of the same subject, photographed

properly, can provide a stereoscopic or three-
dimensional effect. The two pictures are called a
STEREO, a STEREOPAIR, or a STEREOGRAM. The
word STEREOGRAM indicates that the two pictures are
mounted and ready for stereo viewing.

The primary purpose of stereo aerial photography

is to provide measurements, such as height and depth,
and detect features that are not visible in a regular
photograph. Photo interpreters (Intelligence
Specialists) are trained in stereo techniques to detect
these fine points. Stereo photographs are produced by
making two pictures of the same subject from slightly
different positions. When the pictures are made from
the same position, the two are identical and there is not
a stereo effect. A very small shift in the camera
position, between exposures, produces a very shallow
stereoscopic depth. As you increase the shift in camera
position between exposures, the apparent depth of the
stereoscopic view increases. When the stereo effect is
exaggerated--so hills appear steeper and depressions
appear deeper than they really are--the effect is called
HYPERSTEREOSCOPY. The terms inverted stereo,

pseudo stereo, and reverse stereo refer to the effect of

interchanging the position of the pictures, causing hills
to appear as valleys and valleys to appear as hills.

RECONNAISSANCE PHOTOGRAPHY

Another aspect of aerial photography that you

should be concerned with is reconnaissance

p h o t o g r a p h y . T h e N a v y p e r f o r m s a e r i a l
reconnaissance photography of enemy territory to
observe enemy defenses, troop concentrations, troop
movements, enemy strength, and so on. Aerial
reconnaissance photography may also include taking
images over friendly territory, both ours and our Allies.
This is discussed further in the TARPS section of this
chapter.

CARTOGRAPHIC PHOTOGRAPHY

Cartographic photography is accomplished for the

purpose of making charts and maps. Usually several

strips are flown over known landmarks that are used as
reference points or ground-control points.
Cartographic photography always has vertical views

4-6

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Advanced 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 -> might need two, three, or four pictures to show the different sides of a building; or you might make a near and a distant view of the pinpoint target--one to show detail and the other to show location. You can also make more than one shot to produce one large, detailed picture of a pinpoint target. In this case, three or four shots having a 60-percent overlap are made. For example, you may need three overlapping exposures to give a large, detailed view of both ends and the middle of a bridge. When the number of overlapped exposures is small, say four or less, either vertical or oblique photographs, the total composition may be called a pinpoint aerial photograph, but technically, it would be either a strip or a mosaic. STRIP PHOTOGRAPHY A strip is a series of overlapping exposures matched together to form one long picture. A strip is used when your assignment calls for photographing long, narrow targets, such as railroads, highways, coastlines, rivers, and mountain ridges. You may hold the camera at any angle to make a strip; however, exposures made with the camera pointing straight down from the aircraft join together better and have the most consistent scale. A strip comprised of oblique views is called a PANORAMIC. One long, continuous picture, made from a number of photographs, requires the images to be matched carefully so one picture ends where the next begins. Because the camera is in a different position for each exposure, a perfect match is impossible. But, by overlapping exposures and using only the central area of each picture, you can obtain a near-perfect result. Once a strip is started, photographing it is a mechanical job because the aircraft flies at a constant speed and at a constant altitude. You should not alter the camera angle while exposing a strip, and you should make the exposures at regular intervals. Thus the longer the strip, the more an automatic camera system is preferred. The camera-to-scene distance must remain constant while you are making the strip. The smallest change in distance changes the image size and makes matching adjacent exposures extremely difficult, if not impossible. MOSAIC PHOTOGRAPHY Large land areas are photographed in strips that overlap sideways. The strips are pieced together to form one large composite picture, called a MOSAIC. When photographing for mosaic purposes, you should keep the camera the same distance from the scene throughout the photographing evolution. Mosaics are usually produced from vertical photographs made by aircraft with an automatic camera system. STEREO PHOTOGRAPHY Two pictures of the same subject, photographed properly, can provide a stereoscopic or three- dimensional effect. The two pictures are called a STEREO, a STEREOPAIR, or a STEREOGRAM. The word STEREOGRAM indicates that the two pictures are mounted and ready for stereo viewing. The primary purpose of stereo aerial photography is to provide measurements, such as height and depth, and detect features that are not visible in a regular photograph. Photo interpreters (Intelligence Specialists) are trained in stereo techniques to detect these fine points. Stereo photographs are produced by making two pictures of the same subject from slightly different positions. When the pictures are made from the same position, the two are identical and there is not a stereo effect. A very small shift in the camera position, between exposures, produces a very shallow stereoscopic depth. As you increase the shift in camera position between exposures, the apparent depth of the stereoscopic view increases. When the stereo effect is exaggerated--so hills appear steeper and depressions appear deeper than they really are--the effect is called HYPERSTEREOSCOPY. The terms inverted stereo, pseudo stereo, and reverse stereo refer to the effect of interchanging the position of the pictures, causing hills to appear as valleys and valleys to appear as hills. RECONNAISSANCE PHOTOGRAPHY Another aspect of aerial photography that you should be concerned with is reconnaissance p h o t o g r a p h y . T h e N a v y p e r f o r m s a e r i a l reconnaissance photography of enemy territory to observe enemy defenses, troop concentrations, troop movements, enemy strength, and so on. Aerial reconnaissance photography may also include taking images over friendly territory, both ours and our Allies. This is discussed further in the TARPS section of this chapter. CARTOGRAPHIC PHOTOGRAPHY Cartographic photography is accomplished for the purpose of making charts and maps. Usually several strips are flown over known landmarks that are used as reference points or ground-control points. Cartographic photography always has vertical views 4-6 contents Advanced Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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