DOQQ -- Digital Orthophoto
What is the difference
between an aerial photograph and an orthophoto?
-
A conventional perspective aerial photograph contains
image displacements caused by the tilting of the camera
and terrain relief (topography). It does not have a
uniform scale. You cannot measure distances on an aerial
photograph like you can on a map. It is not a map.
-
The effects of tilt and relief are removed from the
aerial photograph by the rectification process to create
an orthophoto.
-
An orthophoto is a uniform-scale photograph. It is a
photographic map.
-
Since an orthophoto has a uniform scale, it is
possible to measure directly on it like other maps.
-
An orthophoto may serve as a base map onto which other
map information may be overlaid.
DOQQ
Specifications
1 Meter Resolution
HTSI can Deliver DOQQ'S
in the following projections:
Universal Transverse Mecator , NAD 83, NAD 27 OR WGS 84 meters
Transverse
Mecator
- Specific STATE ZONE; NAD 83 meters
or feet ; NAD 27 meters
or feet ; WGS 84 meters or feet
State
Plane, NAD 27 NAD 83 OR WGS84, meters or feet
LAT\LON
NAD 83 OR NAD 27 OR WGS84
Lambert
Conformal Conic - Specific State Zone NAD 83 meters
or feet : NAD 27 meters
or feet : WGS84
meters or feet
Image
Formats
TIF- ARCINFO TFW
TIF -MAPINFO TAB
TIF - GEOTIFF (Geographic)
TIF - GEOTIFF (Projected)
TIF - DRG (FGD)
TIF - TIF 6.0
HTM - HTML Format
TIF - TIF 4.0
BMP - Windows Bitmap Format
JPG - JPEG Format (JPW)
MR SID Compressed - SDW
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