| Each enlargement shows an area where a photo
identifiable ground control point is required. A suggested control point
is indicated and described. We try when possible and practicable to
select points which can be directly occupied by GPS survey equipment. If
the suggested point is not recoverable (moved, destroyed) you must
select an alternate point. The alternate must be visible in the image
and away from overhanging trees or tall buildings, to insure that it can
be seen in the matching stereo image. Preference is given to well
defined points on hard surfaces, such as catch basins and pavement
stripes. Refer to our website for more examples of photo
identifiable points and survey
technique. |
