Working with Digitized Topographical maps

CarlPottleCarlPottle Global Mapper UserPosts: 5
edited December 2007 in Raster Data
I started typing this question and while I was doing it I continued to
play around in Globalmapper and discovered how to solve my problem.

I will post anyway to share the result with the forum.

I found a source for Canadian 50,000:1 and 250,000:1 topographical map
data which has been rasterized and projected as UTM (NAD83).
The data is provided as TIF files.

http://ftp2.cits.rncan.gc.ca/pub/canmatrix/

Each individual map is provided as the entire paper map scanned at
300 dots per inch, including the borders of the map. I've attached
a screen capture in globalmapper of two data files just as I loaded them.

I need to make a big mosaic from a series of of these maps without the borders.

It turns out the solution is simple.

1) Open the Control Center "Tools->Control Center...",
select the dataset, click Options.

2) Select the cropping tab. Selected "Crop to Manually Specified Lat/Lon
Boundary". I clicked "Specify Lat/Lon Crop Boundary..." expecting to I
would have to enter the correct Lat/Lon. The default values were correct
(I guess the come from the TIF file). The cropping option
"Automatically Crop DRG-style Collar" works too.

That was simple.

Happy Holidays everyone
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