Looking for handheld GPS unit for fieldwork

April 5, 2011 2:52 PM

What's the best handheld GPS unit for hiking/fieldwork under ~$500?

I'm looking for a handheld GPS unit for fieldwork in the northeastern US. Here's what I'm hoping for in my GPS Mr. Right:

Good signal under forest cover: I'm not going to be deep in the Amazon or anything, but I can expect to be under a lot of tree cover, a lot of the time. I've had problems in the past with GPS units losing their signal in forests.

Waterproof: I'll be doing my work in/near rivers. I'm not going to go swimming with this thing in my pocket, but odds are good I'll lose my footing at a river crossing eventually and it will take a dousing. I do keep equipment in plastic bags when not in use, but, better safe than sorry. In any case, it'll certainly be out in the rain.

Reasonable elevation accuracy: This is possibly a lot to ask - I don't really know what I can expect in terms of elevation accuracy from a consumer-priced unit. I'm not so much concerned with knowing the absolute elevation at a particular location, but I'd like to do the best I can at documenting changes in elevation from site to site.

Those are the big three. Longer battery life is also nice, but I can carry extra batteries. The more waypoints I can enter, the merrier, but this isn't a big issue - I can download points at night, and I won't be marking thousands of sites in a day. It'd be great if it had an easy way to attach a lanyard so I won't have to worry about losing the thing.

I'll be paying for this out of my own pocket. So, the cheaper the better, although I'm willing to go up to ~$500 if I absolutely must. (I certainly can't afford the pro-level units with submeter accuracy - they run for thousands of dollars - but I'd like the most accurate unit possible within my budget.)

posted by pemberkins to technology (18 answers total)

You want this: DeLorme PN-60 as it fits all of your criteria. Elevation isn't super precise, but it's as good as you're going to get for under $500.

Their $30/year unlimited map library download service is a bargain, too.

I've had the PN-40 predecessor for a few years now and it's never let me down.
posted by buckaroo_benzai at 3:19 PM on April 5, 2011

Free Geography Tools has been looking for a good fieldwork handheld GPS for some time and hasn't been satisfied with any. But he just got a Garmin 62s and seems to like it. Here are part 1 atd part 2 of a 3 part review (part 3 still to come). Check his archives too for his opinions on other devices.

For what its worth, I really like my Garmin 60CSx, which I think does everything you want. It works quite well in dense forest (we have lots on Vancouver Island), certainly much better than any other unit I've had the misfortune of trying. I've had it in the rain and dropped it in the water a number of times without any problems. I can't remember how many waypoints it holds, but I've never hit the limit. And it looks like the 62s is a great upgrade to the 60CSx.
posted by Emanuel at 3:23 PM on April 5, 2011

Is there a chance of finding a used professional grade gps in your price range? I have used several cheap models, and have access to nice (and probably very expensive) Trimble models at work. Given a choice, I'd take a couple-year old pro model over a new basic model, simply because they are made to hold up to field conditions, and you can trust the data more. And maybe more important, they are designed for easy data entry and interoperability, which saves many hours of cussing.

If you are just out having fun or geocaching, just buy a consumer model. But for serious field work, you want actual field equipment.
posted by Forktine at 3:38 PM on April 5, 2011

Reasonable elevation accuracy....

FWIW, as a user of professional-grade, many-thousands-of-dollars GPS units, elevation is always questionable. Don't let that be a big factor in your choice. They're all off most of the time. The reason takes too long to explain to get into here, without derailing. Even modestly priced hand-held GPS units can be (but not necessarily are) accurate to within 10 meters or so, maybe even better sometimes, but elevation can be off by a LOT - 100+ meters easy, depending on satellite coverage and geometry.

As Forktine menioned, you can maybe find an older survey-grade unit like a Magellan Mobilemapper or a Trimble Geoexplorer in that price range, but those typically require proprietary software like Pathfinder or ArcPad to use effectively .. and a working knowledge of GIS software.
posted by elendil71 at 3:47 PM on April 5, 2011 [1 favorite]

One more factor to consider: what kind of computer system, if any, do you want your GPS to hook up to? I have the DeLorme PN-40 (predecessor, as buckaroo_bonzai notes, of the PN-60). It's great in many respects (detailed maps, good accuracy, rugged and waterproof), but it does not play very nicely with my Mac. In fact, I've purchased a secondhand Windows laptop just so I can use the software that comes with the DeLorme GPS. (It was either that, or install Parallels, which maybe is what I should have done.)

My only other complaint is that the first time I dropped the "shockproof" unit about three feet onto hard ground, the battery contacts got bent almost flat against the inside of the battery compartment, and ever since then I have to periodically open up the case and use something like a flathead screwdriver to pry up the contacts again or else it will think it has no batteries in it.
posted by Orinda at 5:27 PM on April 5, 2011

Oh yeah, one nice thing about the PN series is that they have a very sturdy lanyard attachment hole molded into the housing. When I'm canoeing, I temporarily replace the original lanyard with a loop of paracord and fasten the GPS unit to the canoe's carry handle or thwart. I capsized in a rapid once and the GPS was none the worse for the wear.
posted by Orinda at 5:33 PM on April 5, 2011

Its a little more than your budget (~$800) but the Trimble Junos are 2-5 meters accurate, run ArcGIS Mobile, and are pretty great all around. Not waterproof though.
http://www.trimble.com/junost.shtml
posted by buttercup at 5:33 PM on April 5, 2011

IMHO, ArcGIS Mobile and any GPS based on Windows sucks a big nut. If Trimble can't even be bothered to write their own GPS operating system, that's a clue that I should run far, far away from anything that they make. I used their stuff (both the Juno and the big ass one they make, I forget the model name) a lot in school and we have them at my job... they are THE most user UN-friendly GPS units I have ever used. The interface is SUPER slow, too. Just typing in data was an exercise in frustration.

Why people pay tons of money for Trimble garbage is beyond me. They must have a lock on the "professional" end of the GPS market (much like ESRI has a lock on the GIS software market, which goes a long way towards explaining why ArcGIS, ArcMap, etc are also buggy shit software that they obviously have little interest in actually improving... they only add enough features -- but don't fix old bugs / issues -- to keep governments, schools, etc on the upgrade gravy train).
posted by buckaroo_benzai at 8:37 PM on April 5, 2011

The Garmin Foretrex 401 has a Barometric altimeter, fully waterproof etc. I have used the 201 when leading groups of hikers.
posted by gallagho at 11:56 PM on April 5, 2011

You might be better off getting a GPS unit with a barometric altimeter and calibrating it on the day at a known point to be honest. GPS is intrinsically not so good at altimetry.
posted by atrazine at 12:52 AM on April 6, 2011

As an alternative have a look at the Motorola Defy and a good map app. It's IP-67 certified (No ingress of dust; complete protection against contact / Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time up to 1 m of submersion).

I cannot say if elevation accuracy is the same, better or worse than a dedicated GPS but you could use maps with elevation data or apply elevation data atferwards.
Battery life is good for a phone, additional batteries are less than $10. With only the GPS receiver on, you should get multiple days of use, depending on how excited you get from looking at a high-resolution screen with detailed maps. This phone can display 10 times as much information on-screen as a PN-60.

It's $300, which leaves room for a case and screen protector, extra batteries, a lanyard and a $5 app. There's no limit to the number of waypoints and you do not need to download anything at night. You will get more functionality than required for the job so you'll have more possibilities to screw up.
posted by Akeem at 2:59 AM on April 6, 2011

Thanks for all your help, everyone! I'll start looking into the models you've mentioned today.

Some responses to your comments...

I'm doing actual factual fieldwork, not geocaching. But, I'm also not trying to draw site maps with submeter accuracy. I just need lat/long info that's accurate enough to get me back to a transect site if I've forgotten what it looks like. ~10m accuracy, if possible, would be great. If the accuracy is +/- a few hundred meters, that's less great.

I do have access to ArcGIS/ArcMap, and to people who know how to use them. I've used ArcGIS before and it still baffles me, but I'll be taking another stab at learning it properly.

I think a better version of my elevation question would be: What kind of elevation accuracy could I reasonably expect from a handheld GPS with a barometric altimeter? This would be mostly for my own edification while I'm in the field - I'll apply elevation data after-the-fact from more reliable sources if I want to use it in analysis.

I'll keep an eye out for an affordable professional unit, but I really don't think I can swing it. Someday, when my research is funded by something other than my personal stipend, I can upgrade. For now, I am solidly in "Poor Grad Student Making The Best Of It" mode.
posted by pemberkins at 6:22 AM on April 6, 2011

Given the merely 10m accuracy requirement, I would certainly look at mobile phones. There is a "better altitude" app for Android phones, and that whole website may be useful to you.
posted by Idcoytco at 10:00 AM on April 6, 2011

Given the merely 10m accuracy requirement

I should say, I'd prefer greater accuracy than this if it's within my budget. I just meant that if ~10m is the best I can expect with an affordable unit, that's okay.
posted by pemberkins at 11:53 AM on April 6, 2011

As a last comment, I'll add that if you get a unit that can load USGS quads and show your position on the map, using the contour lines is often more accurate to determine elevation than the GPS unit itself.

And 10m is about the best reliable average accuracy you're gonna get from a non-survey grade receiver. I dont have any specific suggestions for you since I dont use the smaller units very much, but most personal GPS units in the $100+ range should be fine if 10m +/- works for you. I sent a crew out today with an old Garmin GPS 72 because one of our Magellan's is busted and thats accurate enough to satisfy the clients project accuracy stipulations.
posted by elendil71 at 1:18 PM on April 6, 2011

Free Georgraphy Tools just published part 3 of his review of the Garmin 62s. His conclusion seems to be that, other than if he really needs raster maps, he'll continue to use his five-year-old 60Cx since it has much better waypoint and track handling. By the way, in regards to your requirement for altitude accuracy from site to site, the Garmin 60CSx has a barometric altimeter built in (note that is the cSx, since the Cx doesn't have the barometric altimeter).
posted by Emanuel at 1:27 PM on April 6, 2011

Judging from my experience with the DeLorme PN-40 you will have < 6 m accuracy all the time, and usually less than 4 m even in the woods. I checked it at several USGS points and it was off by less than 4 ft (1.2 m) with a mostly clear view of the sky and good satellite geometry (it self-reported that the accuracy was about 7 ft).
posted by buckaroo_benzai at 1:49 PM on April 6, 2011

You folks, as always, are fabulous. Thank you for your advice! I will post again once I've decided what to buy.
posted by pemberkins at 7:20 PM on April 6, 2011