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trippclark
10-14-2008, 10:27
For those of you who use GPS either on the trail while hiking or to locate trailheads by vehicle, which of the popular formats for coordinates do you prefer?


DMS Degrees:Minutes:Seconds (4930'02"N, 12330'30"W) or (49d30m02.5s,-123d30m30.17s)
DM Degrees: Decimal Minutes (4930.0', -12330.0'), (49d30.0m,-123d30.0')
DD Decimal Degrees (49.5000,-123.5000), generally with 4-6 decimal numbers.

NICKTHEGREEK
10-14-2008, 10:54
I learned DMS nautical and it's my preferred mode for air and sea nav because it's been rattling around in my brain box since the '50's and it was the way my old man taught me.

But UTM is so freaking convenient for land nav you should include it in your poll. You need UTM charts, (there I go again, I mean maps) or a few minutes to transfer a few UTM coordinates to your map, and buy a multiscale roamer.
I thought I had it mastered, but I need to resort to a crib sheet to keep the few rules and fixed distances fresh. There's plenty of good books out there to help you learn starting with the basics and then moving to the advanced skills.

take-a-knee
10-14-2008, 11:29
UTM is the way to go if you can generate your own maps with software. The Nat Geo TOPO is what I use. You can print maps with UTM grids overlayed in red. It makes life really simple, just like using a military map with a protractor.

NICKTHEGREEK
10-14-2008, 11:39
UTM is the way to go if you can generate your own maps with software. The Nat Geo TOPO is what I use. You can print maps with UTM grids overlayed in red. It makes life really simple, just like using a military map with a protractor.
Exactly, you have a system virtually custom designed for GPS accuracy. I use NG Topo also but learned not to use red on Charts/maps because of red lights at night when I was in the service.

take-a-knee
10-14-2008, 13:51
Exactly, you have a system virtually custom designed for GPS accuracy. I use NG Topo also but learned not to use red on Charts/maps because of red lights at night when I was in the service.

That true but I don't think nighttime sniper fire is an issue on the AT, so I just turn a white light on. You could always use a blue light, it serves the same purpose as the red, that is, to preserve some rhodopsin on the retinas. That Nat GEO software will print the grids in black of course

The Old Fhart
10-14-2008, 15:30
Which format is best or others prefer is not really the question. If you are going to be using the shelter and other GPS data from ATC then it would be reasonable to use the same format they use to avoid confusion. What they use is HDD MM.MMM so, for example, Zealand Falls Hut would be N44 11.741 W71 29.657. If you are using the ATC data keep in mind that most of that data is from 2002 and may be a little off.

Jim Adams
10-14-2008, 18:32
uhhhh.....whats GPS?

geek

The Old Fhart
10-14-2008, 18:43
uhhhh.....whats GPS?Like PMS only different.:D

Toolshed
10-14-2008, 21:09
UTMs. Nothing else matters. ;)

trouthunter
10-14-2008, 21:31
I use both UTM and DMS.
I think UTM is so popular because it is easy to understand, you know, 1000 meters is a 1000 meters. A lot of people seem to have trouble understanding how far a minute or a second are.
Lat/Lon are more universal, but UTM is easier. IMO

The Old Fhart
10-14-2008, 22:13
While I agree that UTM is easier to use once you understand it, I have said that it makes more sense to use the format that all your given information is in so you don't have to continually change formats back and forth. The information on the A.T. from the ATC is HDD MM.MMM.

fiddlehead
10-14-2008, 22:26
I agree with The Old Fhart on this one.
I used to use deg/min/sec. but found that google earth, topo 3.0 by Delorme, and some other software was using deg/min/decimal so i started doing this also for the reasons that old fhart gives.
changing back and forth or converting can be a pain.

I studied use of a sextant and ocean navigation before GPS's came out so am fine with deg/min/sec. That system has been around for 500 years or longer.

So, i don't even see the option for the (probably) most common system in your poll.

Ziggy Trek
10-14-2008, 22:42
Yea, just like with the metric system, it's hard to live in limbo when you're old school. Even if UTM does appear to be the way to go (eventually).

trouthunter
10-14-2008, 22:56
Yes I agree, you should use the format your info is in. Not all maps have UTM grids either, so some Lat/Lon skills are needed for a lot of areas unless you draw or overlay the grid.

NICKTHEGREEK
10-16-2008, 16:11
I agree with The Old Fhart on this one.
I used to use deg/min/sec. but found that google earth, topo 3.0 by Delorme, and some other software was using deg/min/decimal so i started doing this also for the reasons that old fhart gives.
changing back and forth or converting can be a pain.

I studied use of a sextant and ocean navigation before GPS's came out so am fine with deg/min/sec. That system has been around for 500 years or longer.

So, i don't even see the option for the (probably) most common system in your poll.
DMS Degrees:Minutes:Seconds (4930'02"N, 12330'30"W)
Is the way my old copy of Bowditch expresses it.

fiddlehead
10-16-2008, 19:42
DMS Degrees:Minutes:Seconds (4930'02"N, 12330'30"W)
Is the way my old copy of Bowditch expresses it.

Yes, but degrees/minutes/decimals is the option i am using as it's what GE uses among others.

If you confuse the two, you'll get close but could still be up to a half mile off.
I learned that the hard way.

ki0eh
10-16-2008, 21:04
Yes, but degrees/minutes/decimals is the option i am using as it's what GE uses among others.

If you confuse the two, you'll get close but could still be up to a half mile off.
I learned that the hard way.

I was once on a trail crew that had a support boat. I was on the boat and we had a scratchy radio connection to the sub-crew on the roadless shore. We were radioing back and forth positions but no sign of each other. We finally realized we had one DMS and other DM.D and...

we both switched!! :D

(Fortunately I switched back quicker than the other guy and we found each other...)

Bearpaw
10-16-2008, 22:37
UTM grid. About the only time I would use Degrees is when talking to aircraft. It's easier for them since their is no confusion about shifting map coordinates for a new 100km x 100 km area.

Otherwise, in the case of the majority of maps out there, UTM is much easier to work with.

take-a-knee
10-16-2008, 23:33
UTM grid. About the only time I would use Degrees is when talking to aircraft. It's easier for them since their is no confusion about shifting map coordinates for a new 100km x 100 km area.

Otherwise, in the case of the majority of maps out there, UTM is much easier to work with.

I always wondered why the flyboys liked lat/long. Now I know.

Bearpaw
10-16-2008, 23:38
I always wondered why the flyboys liked lat/long. Now I know.

With the military alpha-numeric grid designator system, UTM was a nightmare for a jet jocky who was burning in from 400 klicks away. Lat/long was a real necessity for them. Even in the civilian world, search aircraft and resupply planes appreciate lat/longs. For someone moving 2 MPH, UTM is the way to go.

Mr. Parkay
10-17-2008, 00:10
Personally, I hate UTM since it makes it difficult to work with data that spans more than one UTM zone. I usually prefer decimal degrees.

CBSSTony
10-17-2008, 14:20
I get my info from several sources and enter it that way. Then switch the settings to what seems to work at the time, the GPS does the converting.