I created these maps to add another dimension to GPSing; in my opinion, it would be worth all the effort to get them into your GPS. The following JPG images are actually trail maps pertaining to each of the treks we made at Chaco. Each of the maps are down-loadable. Each is comprised of 2 files: the JPG image (openable in any image viewer), and the file associated geographical reference file, called JGW. To use these trails map backgrounds in your GPS, you first need to convert each into a file format readable by your particular brand of GPS. Basically, there are 4 widely-used hand-held field GPS brands out there: Garmin, Magellan, deLorme and Lowrance (numerous GPS makers are on the market, however I will concentrate on the 4 aforementioned brands). Each of these brands has an associated software program which allows users to convert aerial or satellite or scanned paper maps to be imported and used for navigation. 3rd party software for each brand of GPS does not guarantee universal conversion of scanned and electronic maps for use in each brand's myriad GPS models! So, be aware of this potential hurdle. There are certain software available to convert scanned or down-loaded aerial or satellite imagery:
Garmin, the most popular and easiest to use software being: MOAGU/G-Raster. MOAGU will ingest a USGS aerial, satellite or DRG JPG or GeoTIFF product (like these Chaco backgrounds), and allow you to re-project the USGS from UTM (native format primarily usually used by USGS) into Geographic/WGS84 format, and save in a raster file readable by a certain range of Garmin products. At this juncture, Garmin appears to be the only GPS manufacturer that allows ingesting of scanned and other raster maps product into their Dakota and Oregon series GPS units, allowing the user to make free back-ground maps without having to spend large sums of cash to buy aerial, satellite and digital topographics as add-ons! There is one big caveat: Garmin GPS is limited to only 1 megapixel raster image data sets, so all my Chaco trail map back-grounds will be too large!
Magellan, with the Triton release opens the door to users who want to make or down-load free aerial, satellite or digital topographic maps from the USGS; to ingest any of these products, user must acquire a 3rd party software such as Triton Raster Map Maker (Triton RMP, a 1.3 megabyte free-ware program). Triton RMP works with Magellan Triton GPS model only, and the Magellan Vantage Point software by creating the .RMP file usable by Magellan Triton GPS. Be aware that the Triton GPS is the only portable that can handle decent sized raster maps (well over 10 megabytes) like, for example, all the maps in this Chaco trails section.
Lowrance, IF you have a Lowrance road-trail-water cross-over GPS (now discontinued), you could make USGS product map backgrounds for said using a $70 software called: ExpertGPS.
deLorme, as far as I can tell there is no way to import user-made back-ground maps into these products, and no 3rd party software exists to facilitate this. You must use the deLorme software to load digital topographic coverage purchased from deLorme.
By downloading this GPS data and maps, you agree to the following:
To download the following text file for a detailed synopsis of the Chaco trail map's native projection (required if conversion to Geographic lat-lon is necessary for your brand of GPS) Trail map projection file for GPS
To download the following text file for a detailed synopsis of all Chaco trail map details Trail map details file
