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Frequently
Asked Questions
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Q:
What do the FEMA Flood Zone Designations, like AE and X500, mean?
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A:
FEMA Flood Zone Designations
in York
County.
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Q:
I need a map, but
none of your standard ones are exactly what I need. Can you help?
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A: Absolutely!
Providing that we have the data and features that you are looking for, we can
custom-produce any map for you. Please see the map
pricelist for more information.
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Q: What
is a digital orthophotograph?
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A: An orthophoto
is an aerial photograph that has been corrected for terrain/elevation variations,
camera and sun angle, and registered to the earth's surface (imagine a jigsaw
puzzle of the world and each image knows it's position in the
puzzle).
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Q: What
do you mean by the "resolution" of an image?
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A: The altitude of
the aircraft, and lens strength of the camera determine the resolution of the
image. For digital photographs, whether they are taken from an aircraft, a
satellite or on the ground with a digital camera, each pixel represents a
defined portion/area of what the picture is of. Therefore, if the
resolution of an aerial image is 1 foot, what it means is that each pixel in the
image represents one foot (square) of the earth's surface. Satellite
images generally come in 1 meter, 5 meter or 25 meter pixel resolution, while
aerial photos (those taken from aircraft) are generally purchased with
6 inch, 1 ft or
2 ft pixel resolution.
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Q: I'm
looking for old aerial photos of the county - Who has them?
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A: We
maintain some old aerial photos of the county, dating back to 1959. Some
areas are missing, but we generally have solid coverage of the county from 1974
to the present day. We can print or make copies of these photos for you,
but they are not available digitally.
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Q: I'm
looking for old maps of the county - Who has them?
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A: We
do not have any old maps of the county. If you are doing historical
research, you might try visiting the local college libraries (William
and Mary's Swem Library is a good one for colonial-era documents), or the
Library of Congress in Washington, D.C.
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Q: I
need a map for teaching/learning land navigation - will you make one?
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A: The
USGS Quad Maps are generally more suitable to military-style land navigation
courses because they accommodate compass readings (magnetic north), etc.
We always recommend the USGS maps for that purpose. |
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