[Cdt-l] quad maps unnecessary
jonathan at phlumf.com
Mon Jan 27 23:23:21 CST 2014
Yes, USGS has basically replaced the old 1:24,000 "quads" or 7.5 minute maps
with something called "US Topo". The trouble is that most of the "US Topos"
aren't really ready for prime time - from a hiker's perspective. Most of the
default US Topo maps are missing all kinds of key details/layers that were
on the old quads. For example, look at these snippets from the old vs. new
versions around East Glacier Park.
Old quad (1995):
New US Topo:
The old Quad had things like the railroad tracks, power lines,
buildings/structures, the "1-36 mile grids", pipelines, labeled
park/forest/wilderness boundaries, forest cover, private land claims, and
most importantly: Trails! Each of these things can be really useful -
sometimes critical - for hikers. I'd rather have a slightly older quad with
these things than a new US Topo without it. There are some individual US
Topo maps that have these layers added, but they're not very widespread.
This missing information is mostly available for download separately, as
separate layers. You need to go here:
Then you need special software to splice everything back together, and
either a lot of time, or a script wizard to make it all work. Only then, do
you have the problem mentioned below of splicing individual maps together so
the centering makes sense. If you happen to have ArcGIS ($1000/yr) and know
how to use it well, you can likely get this done. But that's not a practical
option for most.
In addition, the default coloration on the US Topos not good - try reading
the stream names on the new US Topos - the blue is too light. The elevation
contour lines are all the same thickness (too thick), making them a lot
harder to read/follow (old maps have thick 200ft lines, and thin 50ft
lines). All the elements are vector graphics,(which means they could fix
these things, btw), and you lose some of the fine details on the older
bitmaps (DRGs) - look at the contours along Two Medicine Creek.
This is all digital information, so all of these issues should be
addressable with time. provided someone is actually working on it. In
addition, since this is all digital you should be able to center such a map
wherever you want, and have it custom-generated. Again, something that you
could probably do with ArcGIS, provided you have the source data files.
As for the comments below about splicing the maps - been there, done that.
though, only with the older USGS Quads. Haven't tried it with the US Topos
due to the issues outlined above.
From: cdt-l-bounces at backcountry.net [mailto:cdt-l-bounces at backcountry.net]
On Behalf Of Glen Winters
Sent: Monday, January 27, 2014 3:30 PM
Subject: Re: [Cdt-l] quad maps unnecessary
The USGS topo's are being updated, the current versions are 2010, 2011 or
2012. http://nationalmap.gov/ustopo/index.html free to download and use as
you desire. If your printer supports poster printing you could print at
home. They do not have the trail information overlaid, at least on the 10
maps I looked at for the PCT area, but do have PDF geolocation data
imbedded. They also have older maps that do have trails marked on the maps.
Otherwise your correct they are headed to GIS mapping. I wish I knew a bit
more about overlaying the trail onto the maps I could make some more options
available for hikers. Larger maps designed to print on 11 x 17 paper for a
wider field of view for off trail exploring and or getting lost. I'm trying
to learn more about it. I'm pretty good at manipulating graphics files, and
could easily merge a few maps together, or write a script to do so
programatically, cut out the pieces that work best, etc, The difficult part
is putting back in the map datum other than manually page by page, selecting
the correct deviation which maybe a degree off depending on which maps are
merged, and making sure the distance scale is also correctly sized, all of
which may lead to errors. The National Geographic map software, that has
been discontinued, used scanned copies of the older USGS topo maps, from
Halfmile PCT maps you can see where the corners of the maps merge from color
differences in the maps. It would be nice to get a group together and open
source something similar.
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