[Proj] Algorithms & Plate Carrée
al001 at uni-koeln.de
Mon Jul 23 08:58:33 EST 2012
Noel Zinn wrote:
"Your question can be interpreted in many ways
and it's not clear to me what you really mean. "
I didn't express myself clearly. Sorry.
For example, given a 1 kilometer square area in
Google Earth, and the same 1 kilometer square
area on a precision digital map made with ground
or aerial survey in UTM-WGS84, there will be an
error when measuring coordinates in GoogleEarth
imagery compared with those on the map for
visible features in both. This error which will
vary over the area because the projections are
not identical in addition to the absolute error
at a given known point as cited by Noel, plus the
optical and atmospheric distortion errors in the GE imagery.
Assuming that one or more points in the Google
Earth image have known coordinates in UTM
obtained either from maps as above or with
differential ground GPS measurement from known
points nearby, and that optical, perspective and
atmospheric distortions can be neglected (?), how
can one correct for the distortion due to Plate Carrée?
Might this be the same as calculating something
like an inverse of a Tissot Indicatrix for the small area?
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