convert GIS maps to Garmin format?

I would like to take the US Forest Service maps and somehow download
them into the Garmin 276c. Is such a thing possible, or are we stuck
with the horribly bland Garmin Mapsource.

If the answer to above is no, then can anyone recommend a hardware GPS
platform that lets us pick and choose from more than the one
proprietary map vendor. For example, I would love to download the
National Geographic topo maps to a GPS unit.

My application is mostly offroads, on trails well marked by Forest
Service maps but displaying at very low res, if at all on Garmin Topo
West.

thx,
tony

iamtonyz@gmail.com schrieb:


Which format are these maps?

iamtonyz@gmail.com wrote:



Compared to Garmin's US Topo, USFS Sierra NF printed map has less
detail and lacks contour lines. The Sierra map is 1:127,000. Garmin
also publishes more detailed 1:24,000 topos for limited areas. Because
Garmin's maps are vectorized and scaleable they are much more useable
than a raster scan would be.

Most USFS maps are in the range 1:100,000 to 1:150,000 so they can't
depict as much detail.

See the recent thread on Mexico maps and you will see that Garmin is a
"platform that lets us pick and choose from more than the one
proprietary map vendor."

HTH

I do not know the format of the USFS maps... I am new to all this
digital cartography. But there is digital vector maps for California
online http://casil.ucdavis.edu/mapsurfer/ for example.

HTH, thanks for the response. I didn't realize that was the situation
vis-a-vis USFS vs Garmin. But when I look at my USFS map, I see much
more detail wrt fireroads... e.g. 7N35 markings... I see none of that
on the Garmin map, and good detail on the USFS map.

Am I missing something??

thx,
tony

iamtonyz@gmail.com wrote:

If by "Garmin map" you mean the 24K Topo series, they are based on USGS
7.5' (24,000:1) maps .. which do not show the USFS road number info. I
believe the same is true for the less-detailed Garmin US Topo (which are
similar to 100,000:1 USGS topos in detail.

OTOH .. the USFS maps do not show elevation contours, at least the ones
I have do not.

USFS and USGS seem to live in different worlds. I once reported a lost
hiker (later found) to the Forest Service in terms of approx Lat-Long
(since I was carrying a GPS) and they said that meant nothing to them,
that I would have to provide the road number as in 7N35 :)

Phil