[Xastir] data in .fgd file for geotiff map

[Tom Russo]

On Tue, Apr 06, 2004 at 04:44:05PM -0400, a Mr. Richard Feyler of Fort Lee, New Jersey <wendell at adsi-m4.com> writes 'Dear Rosanne Rosannadanna':
> I'm using FAA sectionals from
>   http://aviationtoolbox.org/raw_data/FAA_sectionals/current/
> which are (rather large) GeoTiff files.  I have them as maps to
> xastir, and the longitude seems to be right on, but the latitude
> seems to be about 1.4 minutes off.

This could be a result of how xastir deals with maps that aren't in 
lat/long.  The map has to be reprojected from whatever projection it's in,
and to date most of the maps folks have used are in UTM.  It's not clear
that xastir will properly handle maps in lambert conformal conic such as
sectionals, although it does seem to make a valiant attempt.

It doesn't appear that the datum is an issue for these particular maps.
That's often the cause of shifts like the one you see.

-- 
Tom Russo    KM5VY     SAR502  DM64ux         http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 http://www.qsl.net/~km5vy/
 "It is inhumane in my opinion to force people who have a genuine
  medical need for coffee to wait in line behind people who apparently
  view it as some kind of recreational activity."  -- Dave Barry