Eastern Topographics (e-topo.com)
Eastern Topographics - Aerial photography and topographic mapping of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York and New Jersey.
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Targets
In vastly wooded areas, man-made features such as buildings, roads, and telephone poles are not available or are incorrectly situated to be suitable control points. This problem usually occurs in mountainous, heavily wooded areas and necessitates use of pre-flight panels (targets) placed in optional positions within or near the area to be mapped. These artificial targets are then tied into control surveys. These targets will be used for precise measurements and to orient the entire mapping correctly and therefore, care must be used in producing and placing them. Target sizes vary depending on the photo scale.  Use the menu below to find out how big your targets should be.

Round to the higher closest photo scale.
Photo Scale
Cross Target


T Target

PANELS(TARGETS): The panels should be of weatherproof material and should stand out against the background surface. An easy and economical target can be made up with tarpaper and painted white or made of bleached cotton sheeting, white mercerized cotton bunting or white muslin. Caution should be exercised so sun reflection does not render the target useless. For this reason, plastic sheeting or high gloss material should not be used. If the target is to be placed on an asphalt road or paved parking lot, white waterproof paint can be used directly on the hard surface. On any concrete roadway black paint can be used.

When placing the targets, one should refer to the general areas marked by us on the figure accompanying the proposal. Since the aerial photography will occur between the hours of 9:30 a.m. – 3:30 p.m. for Spring flights, and 10:30 a.m – 1:30 p.m. for Fall/Winter flights, be certain that the targets are sunlit and shadow free during these hours. Placement should occur within the red cross and blue squared area on the map just prior to flight time in order to minimize the possibility of damage or loss. The target should be placed on a flat, but not necessarily level spot that is not obscured by evergreen trees or dark shadows. It is best to position the targets anywhere within the marked area that is open and free from deep shadows (i.e. we have asked for a target on the property corner, but that corner is obscured by evergreen trees - it would then be necessary to move the target to an open area such as a swamp or hardwood stand). If it is necessary to move a target more than three hundred feet (300’), please contact us for advice.