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General Category => General Discussion => Topic started by: leapfrogtbdp on October 28, 2009, 09:47:29 AM

Title: Map Quality
Post by: leapfrogtbdp on October 28, 2009, 09:47:29 AM
New to site and just installed NE USA Topo Part 1.
Seems the contours are much better compared to Map Source 1:100,000 but nowhere near the detail of Topo! or the USGS Quads.
Not complaining and appreciate the work everone is doing but just wanted to set my expectations to reality
See attached screenshots
 
Title: Re: Map Quality
Post by: Boyd on October 28, 2009, 10:08:14 AM
Not complaining and appreciate the work everone is doing but just wanted to set my expectations to reality

If you want the "real thing", have a look at the custom maps I have been uploading: http://www.gpsfiledepot.com/maps/byuser/282/

Of course, you will also need to get a Dakota, Oregon or Colorado to use them.  :)
Title: Re: Map Quality
Post by: maps4gps on October 28, 2009, 10:35:38 AM
Your observations are correct.
The map author of the xx USA Topo mapset used a CI of 20ft for the 48 States.  About 1/2 of the USGS printed quads use a CI of 10' or 5'.  This is the only mapset I know of where the author contoured using the 30m NED elevation grid - I believe everyone else (see the individual state maps) used data with a 10m spacing (9 times the number of 'control' points to create the contour lines).
Title: Re: Map Quality
Post by: -Oz- on November 08, 2009, 01:49:56 AM
Yea, as maps4gps said a lot of the other maps use the 10m (or even 3m) data.  The contour interval for the florida map I made is 5ft for example.

I am going to have to get a Dakota just for these new maps.  too cool.