Author Topic: MapSource roads & rec versus topo for touring?  (Read 5246 times)

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Offline vanick

MapSource roads & rec versus topo for touring?
« on: June 13, 2005, 02:18:42 pm »
Does the MapSource topo product have the same level of detail on roads as the MapSource roads & recreation?  I'm embarking on a transam tour shortly, and will be riding mostly on paved roads, wondering which product to buy.  Topography would be nice, but I don't want to lose detail on where the paved roads go!  My GPS unit is a Garmin GPSMAP 76C.  I'd like to be able to use it for navigation in populated areas as well as in the boonies.

Thanks, Nick


Offline Fred Hiltz

MapSource roads & rec versus topo for touring?
« Reply #1 on: June 14, 2005, 11:47:34 am »
US Topo shows almost exactly the same roads as R&R, but without road names. US Topo derives from the USGS 1:100,000 series quadrangles dated from the 1960s to the 1980s. R&R derives from the US Census TIGR data of about the same vintage, and road positions are not very accurate.

For accurate and current road data, City Select derives from Navteq, updated annually and therefore more expensive. It does routing along roads, which is handy on a bicycle as well as in a car, announcing turns before you get there in the GPSMap 76C.

Autorouting confers an unexpected benefit for long rides with the Adventure Cycling GPS routes. You can remove many of the waypoints--perhaps half of them--that serve only to keep the straight-line routes close to the highways. Then you can put much more of the bike route into the 76C without exceeding its limit of 10,000 waypoints. You might be able to get all of the Northern Tier into it. I know that Southern Tier fits.

You can judge the coverage for an area that you know by looking at the different maps with Garmin's viewer at http://www.garmin.com/cartography/

Fred


Offline vanick

MapSource roads & rec versus topo for touring?
« Reply #2 on: June 14, 2005, 12:35:15 pm »
Thanks Fred for the input, I guess I'll go for US Topo.  My tour is Oregon to Virginia via the Lewis & Clark to the trans am east of the Mississippi.  I'm going to attempt to cram a useful set of waypoints into the 76C, I know I'll need to toss out a bunch.

Regards, Nick

www.nickevans.crazyguyonabike.com


Offline Fred Hiltz

MapSource roads & rec versus topo for touring?
« Reply #3 on: June 15, 2005, 01:22:44 pm »
Please let us know how the cramming goes, Nick. Several other people have asked about what fits.

Maybe you will find a kind soul here who lives in the middle of the route and will let you plug into his/her MapSource for a refill.

Fred


Offline vanick

MapSource roads & rec versus topo for touring?
« Reply #4 on: June 15, 2005, 10:44:06 pm »
I'll let y'all know how it goes, the 76C (replacing my ancient GPSIII+) is in UPSland, has not arrived yet.  You've got me looking hard at City Select rather than USTopo.  I haven't ordered either yet, but I do need to get all of this together within the next couple of weeks.  As for the charger situation, I'm ordering a Maha MH-C204W.  Light weight, and it now looks like I'll be carrying at least three non-minimalist techy items that use AA batteries (GPS, PocketMail, camera).

Nick


Offline ptaylor

MapSource roads & rec versus topo for touring?
« Reply #5 on: June 19, 2005, 03:00:12 am »
I would definitely go with City Select. I just finished a portion of the Atlantic Coast Route, and was quite pleased with it.

Paul

Offline vanick

MapSource roads & rec versus topo for touring?
« Reply #6 on: June 26, 2005, 12:12:54 pm »
Well here's the deal.  I've ended up with City Select, thanks for the input.  The maps for my Oregon to Virginia route take up about 100 megs of the 76C's memory (the Roads & Rec data for the same route are about 25 megs).  There's obviously a whole lot more data there with City Select, also obvious when I compare the respective renderings of the local scene.

As for the waypoint issue, there are something over 1800 points in the ACA files that cover my whole route.  The 76C only holds 1000 points.  I'm sure I could toss out a bunch of points by selectively deleting route points marking curves in roads and the like.  But life's too short.  

What I've done is to build a file that has the full data set in more densely populated areas, where the route might be more of a challenge to navigate.  That's mostly in the midwest and east.  I've tossed out large chunks of navigational points in the west, and in Virginia where I've pretty much already been over the whole route at one time or another anyway.  Since I'm going to be mostly camping, I've kept all of the campground points for the whole route.  I'll also be carrying paper maps.

As for the 76C on the bike, I've built an aluminum carrying bracket that centers the thing in my aerobars, which is very nice in terms of viewing distance for my eyes.  I've purchased a set of 2500 mAh Energizer batteries; these seem to have staying power.  I did an 8 hour ride yesterday, and running the thing with the data screen up most of the time (which is black & white, gives speed, averages, time, elevation, and a whole bunch of other possible numbers), rather than having the color map screen on full time & watching myself crawl down a long highway without any intersections, the battery charge indicator never went below full. I've also purchased a Maha MH-C204W charger, with is very light weight as those things go.

So far, so good.  

I'll post an image of my mounting arrangement on my trip website in the next day or so.  Those out there who would prefer to ride without GPS & other techno-gadgetry, have at it!  Nobody's forcing this down your throat.

www.nickevans.crazyguyonabike.com