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GPS: mapping vs. non-mapping, etc


undermind

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Well, I think I'll get a GPS. I'm at that stage where I'm vulnerable to spending a lot more money. When I start researching, I start with the basic models and always end up working up the ladder and spending double the cash.

 

So.. I'll be doing basic mountaineering and off-trail stuff mainly around WA. I don't know a ton about the features, so I'm not sure what I can't live without.

 

I'm questioning the need for mapping capability at this point. I will always have a topo map, which I know will be more detailed than what I'll see on the GPS screen. So I'm leaning toward no mapping. But then the thought of future kayaking creeped in.. Are there any major things that the basic mapping models ($175) are missing from the more expensive ones ($350)? And any reason B/W versions would be inferior to color?

 

Thanks. And by the way, I'm not looking for a discussion about map & compass vs GPS. I always carry a map & compass.

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I'm wary of paying for barometric altimeter function. After all, elevation is a component of any GPS unit regardless of price from what I understand. I think the advantage of having altimeter built in is the ability to check altitude at any time, whether or not you're locked on to enough satelites to calculate elevation.

 

What I am curious about is whether the units with built in altimiter are the only ones that can track and graph elevation gain and loss. And also, can anyone comment on the ability to lock onto enough satelites to calculate elevation around WA in tree cover? Like old growth forest for example..

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The barometric altimeters are generally more accurate (within the limits of changing pressure due to weather) than the elevation caculated from the satellite fix. I often carry my GPS with just the altimeter on to track elevation gain/loss but not drain the batteries.

 

I have never missed having no mapping abilities. Unless they come out with a GPS that has a 19' screen (and still fits in your pocket cantfocus.gif ), I can't imagine using a map on one...

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in tree cover dont count on it, however on alpine climbs you can get very good accuracy from the satellites.

I'll second that. In steep terrain you start to loose satellites and the GPS calculated altitude really suffers.

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in tree cover dont count on it, however on alpine climbs you can get very good accuracy from the satellites.

I would second that, I have been in situations with my ETREX where I wanted to take a waypoint and even up on a ridge, but in the trees, this thing couldn't get but one or two satellites. I was surprised. WTF!? wazzup.gif

 

As far as out in the open, in alpine, awesome!

 

I looked at ones with a mapping function but I would agree, the resolution isn't that great. Stick to the basic models unless you are REALLY into the bells and whistles that come with the more expensive models.

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I bought the Etrex Legend back on sale for $140 or so. Try gpsnow.com

 

I did not pay extra for the mapping cd's and I do not miss them. You should plan on using it in conjunction with a program like TOPO for Washington or wherever as that lets you easily enter waypoints before your trip.

 

B/W screens are not bad, why do you need full color points and lines? If you are buying this as a navigation instrument the full color stuff does not matter. If you like to buy the latest toys for the gee whiz factor then go for it though.

 

As for the inclusion of a Barimetric altimeter I would really prefer to just use my one on my watch. A gps (w/o a specific barimetric altimeter) actually does have the ability to get your elevation but it is less accurate than a well calibrated barimetric altimeter, however the accuracy is still probably good enough for most of what we do in the mountains (+- 100 ft?)

 

 

The only bell or whistle I would be willing to pay much more for would be an improved antenna that could more easily pick up satellites while in the trees. I wouldn't want to spend much more on something like this anyway because your chances of losing something this size or inadvertently destroying it while climbing are too great.

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In an alpine environ I have actually used my GPS with a lot of satellites to set my watch altimeter, and have found that when I reach the summit, it is dead on. GPS measurement is based on triangulation, and it is my understanding that more obtuse angles between satellites yields better vertical resolution. I probably wouldn't trust the given eleveation unless I was in a totally open view with 5 or more satellites, and the reading is stable. If you are thinking about blowing a huge chunk of $$ on your GPS, I would consider the new Suunto watch way before any color mapping doohicky. I think the watch is way more practical in the sense that you would always have it ready for measurement. If I wasnt going to blow a huge wad of $$, I would look at the etrex gecko. I would have bought the gecko instead of my etrex venture if it had been out at the time. Geckos are light weight and easy to use. I think in the long run you will use it way more with those charachteristics compared to the handful of times you might acutally use color mapping or something.

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i used to 100% agree that the mapping function seems like an unnecessary bell and/or whistle with such a tiny screen - if you have enough detail showing to be useful, i said to myself, you can't see enough terrain to know where you want to go.

 

but then, last spring, i went on a trip with a guy who had a color mapping gps, and guess what, it was really helpful. of course you still need a paper map for large scale decision making, but the map on the screen really simplified locating your position from the gps onto the map.

 

assuming, of course, that you need a gps at all. i don't personally own one, and for the cascades i seldom feel like it is worth the weight, but there are certainly times and places for the technology.

 

BTW, for waypointing software, i highly recommend USA Photo Maps, a free download that stitches USGS topo maps and aerial photos, lets you input routes & waypoints, etc., available as freeware.

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Forest, I dunno if you are referring to my GPS, but, yes, I find it extremely helpful.

 

As he said, it doesn't replace a map, but it can really speed up quick and dirty navigation. I used it for 2 days over the ptarmigan traverse in a virtual whiteout. I sent my friend first to do crevasse navigation while I hung back and gave him general directions. We hit the cols between glaciers within 50 feet every time. Pretty nice.

 

-josh

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I like having the altimeter on the gps as a backup to my watch, especially since there is no weight penalty. I've had my watch go out a couple of times and I used the gps for altitude (barometric readings, not triangulated altitudes; I haven't found triangulated to be consistently accurate compared to barometric)

 

Also, having both mapping and non-mapping gps's, I would never go back to using a non-mapping one (yes, I haven't used my garmin 45xl in years). As for color vs. b/w, exactly how many people do you know who have monochrome monitors on their computers... bigdrink.gif

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Thanks for the reply's, good info.

 

I've been considering the usage I would get out of a GPS.. And the main thing that comes to mind is helpfulness in whiteout conditions. But I don't plan on having a lot of that. smirk.gif

So I think a way that I can make a purchase more justified is to have altimeter functions. That way I could at least want to take it on all of my backpaking trips so that I can view elevation gain/loss and charts. This is completely for fun factor. I can't think of another reason to bring a GPS along if I'm never going to leave the trail.

 

So that leads me to a few models. The Garmin Geko 301 ($180) and the Garmin Vista ($230). So basically, it's a matter of whether I want to spend $50 extra for mapping capabilities. As far as I can tell, both of these models are similar in GPS features. Both have altitude and compass abilities, which has become my main focus.

 

So maybe someone can help me get a grasp on just what the mapping functions are. Do the mapping units allow you to pull up actual visual tracking ON the map of your routes taken? And I mean on the GPS screen in the field, not at home on the PC. What CAN you do with the map that's useful? If the map is there to just "look at", then I don't see how that will beat out my paper map.

 

Will mapping be more useful in sea kayaking? It seems it might be a similar situation..

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Undermind,

 

I have the Vista and have used it for several years. It can show you where you are on the map, your track and can oriented to either "north up" (where north is the top of the screen) or "direction of travel" (where the top of the screen is the current direction you are heading). You can download maps into the gps for different uses. Some of the maps available are for roads (for car navigation; somewhat useful if you're a passenger but not practical for driving) topos (at 1/100,000 they're nowhere near as good as 1/24,000 quads, but they are useful enough for get oriented). Typically, what I do is put in waypoints into the gps which I also put onto a paper map. I use the gps for navigating (refering to the paper map if needed/wanted; the waypoints on the map make it easy to go back and forth between the two) and for putting in waypoints as I go (kind of like "elecrtronic wands")for the trip back. I've never had my gps go out, but if it did then I would be able to move seamlessly from electonic map to paper map and compass.

 

Personally, I like having the mapping capability and think it's worth the extra $$$ for the ease of use it gives. When I've been climbing all day, am tired and have a case of the stupids, I like not having to wonder where the heck I am.

 

Hope this help some... bigdrink.gif

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Get the geko... Shave a bit of weight and price. I went with a mapping GPS and haven't found mapping useful. Current maps aren't good enough for getting a good read on the features that you want to know about on a cascade mountain, and can even be misleading (like, whoops, how did we end up cliffed out?) You carry a map and compass, and obviously know how to use them. Setting waypoints at home or on your way up will provide the backup security you are looking for. Another obvious but good idea is to really play around with it before you start to use it in the mountains. For example, I figured out that the altitude feature can be really useful at an estimated gps accuracy of 8-10 feet, but at an estimated accuracy of 30 feet altitude can be off by hundreds.

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For example, I figured out that the altitude feature can be really useful at an estimated gps accuracy of 8-10 feet, but at an estimated accuracy of 30 feet altitude can be off by hundreds.

Sweatinoutliquor, can you explain? I don't quite get what you're saying here.

 

Eastsider, you mention you can "track" on the map. Can you at any time pull up the map on the GPS screen and show the path that you have taken?

 

JoshK, what areas can you get 24k maps for in WA? Do you have a link?

 

Also, I've read that you absolutely can only load maps from Garmin onto the GPS. And these seem to cost $99. Pretty harsh. I've seen a Western US topo map cd. Are there any alternatives to the $99 cd? At this time, I only need WA. Beyond would be nice, but I think it would be nice to pay smaller prices for more focused areas. I'm only interested in topo maps.

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Also, I've read that you absolutely can only load maps from Garmin onto the GPS.

garmin has been hacked and you CAN make your own maps. this link looks like a great source.

i know there is also a way to take your own drg's (georeferenced topo images) from any gis software, run them through a 3rd party conversion, and load them into garmin.

i just recently got my gps, and i haven't had much time to test any of this out.

 

JoshK, what areas can you get 24k maps for in WA? Do you have a link?

i'd like to know too!

 

-r

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Don't use your GPS for altitude unless your are in open terrain. The can't be trusted. My garmin has been off 100's of meters in elavation. difinitely get a barometer type for elavation. I have a casio watch with the function.

gps work poorly in steep forests or dense forest. they are good in the open realy.

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Eastsider, you mention you can "track" on the map. Can you at any time pull up the map on the GPS screen and show the path that you have taken?

 

 

U-

 

Sorry I didn't get back to you sooner, I've been away from the computer for a couple of days.

 

Yes, you can show the track of where you have been in with the map up.

 

E-

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I bought an Etrex. And promptly returned. The next GPS I buyu will have full map capability, a buttload of memory, and a bar altimeter. Without those feature it´s a halfassed tool in my opinion. Unless all you want to do is go geocaching.

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