good lord..coordinating my GPS to USGS maps is giving me fits!!

[vash]

i think i am getting it..but man, what a trek!!

i want to have paper maps with me in the wilderness, and fire up the GPS occasionally to locate myself.

i switched my unit to UTM-UPS..and the datum to NAD 27 CONUS..now what?

i guess i need a map of my current position to learn this..i only have maps of other places.

any tips for a dummy?

[trekkor]

but man, what a trek!!

Garsh...


KT

[lm6y]

Draw out your grid lines, and get one of these.

UTM / MGRS Tools

[vash]

thanks!!! that booklet they sell looks great!! maybe i will hit the local book store too.

thanks for the idea, brent.

[lm6y]

No problem! I've actually used the grid tool. It takes a bit to get comfortable using it, but once you do, it's second nature.

[vash]

they sell that grid thing at REI.

i just ordered six books from my local library. i am all over this.

[GH85Carrera]

NAD 27 Conus is a very old (1927) datum. There are a lot of errors in it. NAD 83 is much better but you have to work with what you have.

[GH85Carrera]

I am not a surveyor so I know my limits of knowledge. UTM="Universal Transverse Mercator" and UPS="Universal Polar Stereographic" Just because I am curious why are you using UPS? That is to map the polar regions.

[vash]

Originally Posted by GH85Carrera

I am not a surveyor so I know my limits of knowledge. UTM="Universal Transverse Mercator" and UPS="Universal Polar Stereographic" Just because I am curious why are you using UPS? That is to map the polar regions.

honestly..i dont know.

i just figured out the acronyms the other night. here is what i do know. i have a few topo maps. in the lower corners, it shows the units and datum. i have to set my GPS to those same parameters. that way, i only need to power up the GPS, get the coords of my current location..and find myself on a paper map.

i think a limitation to downloaded maps is the tiny screen. i see myself no problemo..but i cant scroll out to see a nice ridgeline, with a basin and timber growth..

just trying to use my GPS to the fullest.

[GH85Carrera]

Just guessing but I would suspect those paper maps are either in WGS84 or UTM NAD27 Zone10 (or Zone 11 if you are in Southern Cal.)

One of the mapping programs we use can re-project a digital map. It is crazy how many different projections are available. I always wanted to make a map in datum like Interplanetary, Jupiter, or Beijing 1954.

[LakeCleElum]

I volunteer with the local Search & Rescue. We've recently switched from NAD 27 to Utm CODES.....If someone is lost/hurt and call in their Lat/Long, I can sit at the computer in the Command post and convert it.

There are new standards coming out for SAR, all switching to UTM is just a matter of time...

What I do when out snowmobiling and dirt biking, is mark my points on the GPS at times and give them names I'll remember. Example, We have a hard to find local "secret trail" to drop into a canyon. I just marked the spot and named it: "Drop over the side". G'luck.

[emcon5]

GPS? Pussy.

Military Prismatic Sighting Compass w/ Pouch: Amazon.com: Sports & Outdoors

[id10t]

Originally Posted by emcon5

GPS? Pussy.

Military Prismatic Sighting Compass w/ Pouch: Amazon.com: Sports & Outdoors

Yes, while a real compass is needed, they really don't help much with locating where you are at when you are in flat, brushy terrain... like most of Florida. In mountainous areas, they do help, since you can actually get stable points of reference that you can see above the tree/brush line

[emcon5]

Originally Posted by id10t

Yes, while a real compass is needed, they really don't help much with locating where you are at when you are in flat, brushy terrain... like most of Florida. In mountainous areas, they do help, since you can actually get stable points of reference that you can see above the tree/brush line

I actually learned to use it in Florida.

[RWebb]

older maps are harder to use with a GPS as they lack some of the annotations that more modern ones have

not sure I recall all this as it has been a loooong time... but one thing is to locate your basic (coarse) location -- then go to the SW corner of that box (lower LH) and use the Northing and Easting to dial it in

you can change the GPS unit to match UTM or whatever is on your map