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rafe
03-30-2017, 07:51
I've always wanted one, and finally got one. Casio Model 3439, $50 at Costco. It's got an electronic compass, too.

Anyone here have experience with altimeter watches?

It seemed to work OK on last weekend's little hike in the White Mountains. The altitude readings seemed about right, and the reading returned to within 50' of the where it had been when we got back to the car.

Parked here at home, the altitude reading follows the barometric pressure. Weird and amusing to see. Best I can figure, here at sea level, 0.1" of Hg (norm = 30") corresponds to about 92 feet of altitude change. All I know is the indicated altitude has wandered over hundreds of feet, with the watch sitting on my dresser.

As a barometer, the reading seems to agree with official numbers to within 0.05 in. Hg. Probably can't expect much better than that.

Turtle-2013
03-30-2017, 08:04
I use a different brand of altimeter ... but they have to be reset at every opportunity. That is the nature of a true altimeter (as compared to altitude from a GPS). When you are hiking use the given altitude points on the map, or in the guide to reset it. Since an altimeter is just a barometer accurate enough to give you altitude change ... all changes in the weather will affect it. NOTE: Even an un-set altimeter will give you a pretty good altitude "change" number during an assent or descent of a mountain.

cmoulder
03-30-2017, 08:05
That's about it... with barometer-based altimeters the reading is only as good as the last reset, depending upon the weather system. If you really, really need accuracy, it is a good idea to confirm and possibly reset every time you arrive at a known elevation.

I have the Pathfinder (similar Casio module) and what I've come to find most useful is the barometric graph... check the overnight trend in the morning and get a feel for what's up with the atmosphere.

For a set-and-forget solution—which I really never need any more—the best option has been something like a Garmin eTrex 30 with the altitude auto-calibration feature enabled. It is basically a barometer-based altimeter but resets itself when it gets a bunch of very strong satellite signals that are a certain variance from the current altitude reading. It then resets itself from the satellite data and resumes barometric readings. It is almost always spot-on, but I rarely carry the eTrex these days.

Starchild
03-30-2017, 08:18
I had one years ago, before GPS were common, yes it does take time and maintenance, just something you get used to. You end up resetting it when you are at a known elevation or if you somehow know the barometric pressure. Usually noting the elevation before bed and resetting it to that in the morning.

On the plus side it is highly accurate and if traveling up's and downs can pinpoint your location on a topo map easily, but not so much for flats.

It can also be used for relative elevation change for times you don't want to calibrate it, such as it's reading 2390 ft and you are at 2790 ft, you known you have 2000 ft to ascend, just leave it alone and know your destination on the watch is at 4390.

Also the electronic compass eats batteries, even with their occasional instant read use.

colorado_rob
03-30-2017, 08:26
I'm trying to mentally count, I think im on my fourth, but our primary activity is climbing mountains, where altimeters are of course extremely useful. A quick look at a wrist is more convenient for me, at least, than dragging out a phone or a gps, etc, and the newest barometric altimeters (like your casio) are almost as accurate.

My first was an ancient mechanical thing, not a watch, hung on a biner on my pack, I dont remember it being very accurate. The next two were suunto vectors, decent instrument, fairly accurate, but tended to drift low roughly 7 percent when climbing, a few hundred feet over 4000 feet on vertical. Easy to mentally compensate though. I finally think i figured out why; made in Finland, the atmosphere profile changes significantly at much higher latitudes.

Both suunto's finally died (leaky seals after battery change), and maybe 5 years ago I bought a Casio for 60 beans, and it is by far the most accurate altimeter I've owned, even bought two more for wife and son. So, assuming yours is similar, great choice!

So useful for navigation, weather forecast, etc, i never leave home without one. Literally, it is my regular-life watch too. It goes without saying that one should calibrate at known altitudes quite often, when one remembers, that is.

ScareBear
03-30-2017, 08:52
I'm trying to mentally count, I think im on my fourth, but our primary activity is climbing mountains, where altimeters are of course extremely useful. A quick look at a wrist is more convenient for me, at least, than dragging out a phone or a gps, etc, and the newest barometric altimeters (like your casio) are almost as accurate.

My first was an ancient mechanical thing, not a watch, hung on a biner on my pack, I dont remember it being very accurate. The next two were suunto vectors, decent instrument, fairly accurate, but tended to drift low roughly 7 percent when climbing, a few hundred feet over 4000 feet on vertical. Easy to mentally compensate though. I finally think i figured out why; made in Finland, the atmosphere profile changes significantly at much higher latitudes.

Both suunto's finally died (leaky seals after battery change), and maybe 5 years ago I bought a Casio for 60 beans, and it is by far the most accurate altimeter I've owned, even bought two more for wife and son. So, assuming yours is similar, great choice!

So useful for navigation, weather forecast, etc, i never leave home without one. Literally, it is my regular-life watch too. It goes without saying that one should calibrate at known altitudes quite often, when one remembers, that is.

I still have my Suunto Vector. It paid to buy the maintenance packs, which included batteries and O-rings and other stuff. I'm on my second band, the first one just kind of started randomly cracking and literally fell off the watch. But, it did last 10 seasons....

It's just too much fiddling with to get the same data from my phone or my GPS. It was fun for recording total elevation while skiing, although my smartphone does a far far far far superior job at recording GPS data and tracking elevation with the right app....

ScareBear
03-30-2017, 08:53
The Vector is too much fiddling with to get the same data...

StubbleJumper
03-30-2017, 09:06
At $50, it's pretty hard to lose. When hiking, I almost always wear a watch as part of my navigation kit (ie, 30 min = 1.25-1.5 miles). Rather than my Timex, I could see myself buying the Casio with the altimeter.

In terms of actually using the altimeter, I currently just use my phone, and I don't use it often. On a few occasions, if you know that there's a cabin in the woods at 1900 metres, then it's good to monitor how close you are to where you need to enter the woods. Last year, I walked right past a cabin where I notionally wanted to spend the night because I was a little lax about checking altitude. I wouldn't generally need to look at it as often as I glance at my watch, but for $50, what the heck.

peakbagger
03-30-2017, 09:10
I have used them for 20 plus years. They are not a forever watch they wear out. The full featured casios frequently try to do to much and the displays on some models are fairly small. The buttons tend to wear out on Casios. Its takes few years but eventually one of the frequently used buttons will get hard to use and eventually stop working. There was brand "altigear" that made good fully featured ones with large displays, they appear to be out of business. I currently have a Suunto. It looks nice with black background but the contrast with the light colored numbers is poor. Its adjustable but the adjustment doesn't help much.

Changing the batteries is usually a major trauma to these watches. I generally guess that a battery change is going to half the life. There are Orings that in theory need replacing but I expect few watch shops (if they still exist) would have the right one. If I get two battery changes on watch I feel lucky.

All the observations of the accuracy is spot on, the barometric pressure changes and if you don't keep the watch set to known points it will be off on elevation, this obvious depends on weather, if there is steady high pressure above it can be dead on all day, if there is weather coming in with change in air masses it can be off quite a bit over the course of the day. That being said most of the time I am hiking its close enough for my purposes which is mostly to answer the dreaded "when are we going to get to point X" I also use mine for bushwhacks.

Some folks use GPS altimeters as an alternative but they to have a fundamental flaw that the earth isn't round and there are areas that have dips and hills due to various geologic phenomena . The GPS has a model of the earths surface in it but its not going to pick up the dips and hills so the altimeter read the altitude to theoretical mathematical model of the earth versus an actual one.

ScareBear
03-30-2017, 09:24
GPS altitude is more accurate than pressure altitude. Period.

Leo L.
03-30-2017, 09:28
During our most recent trips, my two friends had an electronic watch each, including a barometric altimeter.
All in all we had three ways of knowing the altitude, their watches, one dedicated GPS and my smartphone GPS.
My smartphone usually had just a rough guess about the altitude (like +/+30m), the dedicated GPS was the most accurate and the watches were somewhere in the middle.

The most useful feature on the watches was the graph of barometric pressure change, to be used as a weather forecast. The one time it indicated a constant and heavy drop in air pressure over the day we had a thunderstorm in the evening.

I dont really know why the dedicated GPS got the altitude so precise. The GPS System per se is not accurate in that, by design its more focussed on the position than the altitude.
Maybe the high altitude precision stems from a stored 3d model of the earth surface.

tarditi
03-30-2017, 09:37
I wear a Casio G-Shock Riseman... frankly, I got it because it was a good deal on a solar tough watch at the time (no pun intended!).
Most of the data acquisition features are useless to me because you need to know some arcane sequence of function button click, and some are only accurate when motionless and/or the watch is off of your wrist (like the thermometer). Too much fuss for me, personally.

colorado_rob
03-30-2017, 09:43
GPS altitude is more accurate than pressure altitude. Period.With respect, I just haven't found this to be the case, and our GPS unit is a very recent model.

If calibrated at a known (but lower) altitude and the day's weather is stable, my latest altimeter usually locks in to the nearest 20-30 feet at a summit even after a multi-thousand foot climb, and I've found GPS's can be off more like 50 feet or so on summits of known height (or other times spot-on, but then again, my altimeter sometimes is spot on as well). As Leo just said, GPS's are remarkably accurate for position, but less so for altitude. A look at GPS triangulation geometry shows why this is.

peakbagger
03-30-2017, 09:52
GPS altitude is more accurate than pressure altitude. Period.

I agree that a GPS with WAAS implemented will give you a more accurate altitude if you have good signal. The GPS's I have used attempt to keep a WAAS lock but when in marginal signal territory (dense cover and mountainous areas), it will revert to a non WAAS signal and then the altitude can get less accurate. The trade off on most GPS units is that battery life is less with WAAS enabled. I expect its caused by the GPS making requests more often for a position fix as WAAS is ultimately was designed for aircraft positioning where altitude is critical and thus I think they check every 5 seconds for the DC. All I know is if I go out doing AT boundary with WAAS enabled I burn up a set of batteries in a day, with it off I get a couple of days.

Its non issue for me as I don't bushwhack actively with GPS, far too likely for it to get caught on a branch and fall off or attempt to hang me plus I am not a fan of burning batteries where a altimeter watch does all I need my arm.

Leo L.
03-30-2017, 10:46
First time I hear about WAAS, and reading the short Wikipedia article it seems to be somewhat similar to DGPS, namely a set of ground stations constantly sending correcting signals that take care of atmosphere inconsistencies and similar negative influences for the GPS signal.
Using WAAS drains the battery faster because its a signal separate to the original GPS signal (separate receiver circuit listening) and needs additional computing power.
Available only in North America.

As we, Europe-based, had been in the Middle East, WAAS sure had not been present.
My wild guess is still, that dedicated GPS Units (good ones) have a world wide elevation map built-in.

jimmyjam
03-30-2017, 11:13
I have the Casio and I like it. I find it useful in giving me an idea of how much further to the top or bottom of the mountain. I usually recalibrate the elevation once a day while hiking.

Secondmouse
03-30-2017, 12:44
GPS altitude is more accurate than pressure altitude. Period.

Suunto Ambit uses GPS referenced/corrected baro pressure. best of both worlds - accurate but doesn't chew battery by staying in constant sync with GPS...

Miner
03-30-2017, 16:04
For hiking, I prefer an altimeter watch that hangs on a cabiner rather than my wrist. I leave it hanging off a d ring on my shoulder strap. Flip it up when I want to look at it. On a defined trail with a good map, makes it easy to find where you are.

CoolBobby
03-30-2017, 16:10
I use a Casio Pro Trek 3500 and I love the damn thing. It lives in FL, and has been up to 12k footers in Colorado and on the Knifes Edge in Maine. I have never reset it and have had consistent readings that are within 25 to 50 feet of published altitudes.

cmoulder
03-30-2017, 16:32
I use a Casio Pro Trek 3500 and I love the damn thing. It lives in FL, and has been up to 12k footers in Colorado and on the Knifes Edge in Maine. I have never reset it and have had consistent readings that are within 25 to 50 feet of published altitudes.

You have a watch like no other, for sure. :)

rafe
03-30-2017, 17:22
For hiking, I prefer an altimeter watch that hangs on a cabiner rather than my wrist. I leave it hanging off a d ring on my shoulder strap. Flip it up when I want to look at it. On a defined trail with a good map, makes it easy to find where you are.

I hear you on that score. The Casio 3439 is fat and bulky. I'd never wear anything like that around the house or at work or in "polite company." In real life I wear a Grenen wristwatch, specifically for its low profile.

I navigate mainly by map, no Guthook yet, so the watch seemed like a nice way to augment that. I generally think of a given hiking day not just in distances but in terms of the major verticals. Also, nice to have some real data for the total vertical in a day's peakbagging.

TX Aggie
03-30-2017, 17:22
There are two ways GPS measures altitude. The first is with a base map where it just references the altitude indicated on the map. This is quicker and easier to calculate and requires fewer satellite pings.

The second is a true 3D plotting from all available satellites, which calculate based on a more accurate triangulation model. This is the system aircraft use (obviously). This system doesn't work as well close to the ground because with with an aircraft, they are able to get pings from satellites farther towards the horizon which gives a much greater degree of triangulation.

gpburdelljr
03-30-2017, 17:42
My wild guess is still, that dedicated GPS Units (good ones) have a world wide elevation map built-in.

Even the most expensive GPS units do not use a built in elevation map to determine elevation.

gbolt
03-30-2017, 20:03
Someone on here last fall talked about German Lad Weather Watch on Amazon. I finally ordered one for $45 and have used it on one trip. I don't wear a watch other than hiking because I have my phone out enough. But with poles, it was nice to have quick glances at time, weather, and Altitude. The altimeter needs set as has already been mentioned but it worked nicely. The Compass wasn't as good as on the phone and the thermometer is useless on a hot sweaty wrist; but I figured out that it was close if you subtract 20. However, it is the best under $50 Watch that I have owned and prefer it over Casio and Timex that I am familiar with. Just another option to consider.
I thought you might be interested in this page from Amazon.

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Starchild
03-30-2017, 21:07
Even the most expensive GPS units do not use a built in elevation map to determine elevation.

I've never heard of such a thing either, if anyone could; provide such a link I would appreciate it.

What some smartphones do use is known WiFi hotspots to help determine location which may include elevation.

Starchild
03-30-2017, 21:07
Even the most expensive GPS units do not use a built in elevation map to determine elevation.

I've never heard of such a thing either, if anyone could; provide such a link I would appreciate it.

What some smartphones do use is known WiFi hotspots to help determine location which may include elevation.

TX Aggie
03-30-2017, 21:31
I know of at least 3 common GPS systems that use satellites for altitude vs base maps.

The first is aforementioned aircraft GPS, for obvious reasons. (GPS guided munitions for that matter as well.)

The second is on surveying equipment. If you've ever seen road workers on the side of the road holding a yellow stick with a white dome on top, it's a GPS unit, and those use satellites for altitude to get a true elevation change.

The third, and it's actually a subset of the second, is on excavation equipment. On front loaders, you'll actually see the receivers at both ends of the bucket. This is so they know how far down they've dug.


Sent from my iPhone using Tapatalk

Captain Bluebird
03-30-2017, 22:11
I use a Casio Pro Trek 3500 and I love the damn thing. It lives in FL, and has been up to 12k footers in Colorado and on the Knifes Edge in Maine. I have never reset it and have had consistent readings that are within 25 to 50 feet of published altitudes.. I have the Pro Trek as well! I paid around $165 for it two years ago. I like it. Solar powered, don't have to worry about batteries. I like the temp readout especially when hiking in the Early Spring.

CoolBobby
03-30-2017, 22:19
You have a watch like no other, for sure. :)
Lol... Maybe, but i did buy it used from this site! The watch is indispensable in my eyes. It's got a crazy amount of features, solar charged, and nuclear time. If only it would boil water...

Sent from my SM-G930F using Tapatalk

Dogwood
03-31-2017, 00:00
With respect, I just haven't found this to be the case, and our GPS unit is a very recent model.

If calibrated at a known (but lower) altitude and the day's weather is stable, my latest altimeter usually locks in to the nearest 20-30 feet at a summit even after a multi-thousand foot climb, and I've found GPS's can be off more like 50 feet or so on summits of known height (or other times spot-on, but then again, my altimeter sometimes is spot on as well). As Leo just said, GPS's are remarkably accurate for position, but less so for altitude. A look at GPS triangulation geometry shows why this is.

I find the same thing. I think it's because we both go up to 15K+ ft, will bushwhack in deep forest, jungle, and do desert pancake hikes, use our higher end multiple sensor ABC watches in critical sports applications/activities(climbing for example), and travel broadly and remotely outdoors taking on these activities requiring a critically high degree of accurate dependability. For me a 50-100 ft altitude inaccuracy discrepancy in a jungle or not being able to triangulate 4 satellites with a 95% FULL TIME reliability can have me lost, cliffed out, crossing the wrong international border, or perhaps on the wrong summit.

Leo L.
03-31-2017, 01:35
Even the most expensive GPS units do not use a built in elevation map to determine elevation.
So how else would it work?
I've just the experience of our last hike, where the dedicated GPS had a world map stored including contour lines, and it had the most accurate elevation reading of all devices we carried.

The way GPS works technically results in a better accuracy for position than in elevation calculation, thats a plein fact. The solution is not as simple as reading more satellites, else the smartphone would simply do the same (on some apps you can see how many and which satellites are in the scope - most of the time numbers from 6-9).
Its also not as simple as reading the barometric sensor data, otherwise all GPS apps would do it.

Will do more research into this topic...

BTW, all the survey and construction machinery GPS use DGPS (Differential GPS) or similar setups, which can read separate correction data to avoid most of the very many negative influences to the GPS data sent by the satellite.
Some even manage to jump from runtime measuring to phase detection which was originally reserved for the military and would give accuracy down to single cm. This works especially well for a dual GPS setup where all you want to get is the relative difference of the two units (like in the excavator sample above).

TX Aggie
03-31-2017, 07:54
So how else would it work?
I've just the experience of our last hike, where the dedicated GPS had a world map stored including contour lines, and it had the most accurate elevation reading of all devices we carried.

The way GPS works technically results in a better accuracy for position than in elevation calculation, thats a plein fact. The solution is not as simple as reading more satellites, else the smartphone would simply do the same (on some apps you can see how many and which satellites are in the scope - most of the time numbers from 6-9).
Its also not as simple as reading the barometric sensor data, otherwise all GPS apps would do it.

Will do more research into this topic...

BTW, all the survey and construction machinery GPS use DGPS (Differential GPS) or similar setups, which can read separate correction data to avoid most of the very many negative influences to the GPS data sent by the satellite.
Some even manage to jump from runtime measuring to phase detection which was originally reserved for the military and would give accuracy down to single cm. This works especially well for a dual GPS setup where all you want to get is the relative difference of the two units (like in the excavator sample above).

Good additional info. I'm not technical enough to know all the difference the higher end GPS systems have, but I know a lot of it simply has to do with antenna sensitivity (size in many cases) as well as processor speed. I also understand that there is a separate military frequency as well as additional satellites for military use and they have the ability to block its use in certain regions.


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rafe
03-31-2017, 08:16
Well what the heck, think I'll take it skiing today and see how that goes. Not much vertical but consistent deltas, eh?

Barometer is steady even though there's some kind of storm predicted. Actually the weather people seem sincerely conflicted about what may or may not fall out of the sky in the next 24-48 hours.

This particular Casio I've got has a thermometer too but that part is kinda stupid, and not why I wanted it. When the watch is worn on the wrist, whatever reading it might give is meaningless. It is highly influenced by body heat. I suspect the thermometer is mostly there to assist with linearization or other compensation of the barometer.

Time Zone
03-31-2017, 08:36
I too have a Casio that does barometer, temp, and altimeter. I agree with what others above have said ... the altimeter works only when a) calibrated first and b) no big changes in barometric pressure due to weather (as opposed to altitude - that's how it works). Agree also, temp is useless if it's on your wrist. You have to take it off for 20+ minutes (and hang by a carabiner say) for it to equalize with the ambient temp.

I will say that with a steady barometer I did find the altimeter to be dead on accurate for an ascent/decent. Other than that I usually just use it as a guide.

One thing worth mentioning for watches in general are that it's wise to note the time elapsed since your last landmark and when you expect to see the next one. Either keep track using the time function or the stopwatch. If you know your usual pace for the terrain/elev change, you can estimate with some accuracy when you should come across the next landmark. This is an important mental habit when hiking in areas that are not well marked - it can give you a sense of when to backtrack to see if you've missed a turn. It also heightens your senses to watch out for such turns and landmarks, reducing your chances of missing them in the first place.

rafe
03-31-2017, 08:46
I too have a Casio that does barometer, temp, and altimeter. I agree with what others above have said ... the altimeter works only when a) calibrated first and b) no big changes in barometric pressure due to weather (as opposed to altitude - that's how it works). Agree also, temp is useless if it's on your wrist. You have to take it off for 20+ minutes (and hang by a carabiner say) for it to equalize with the ambient temp.

I will say that with a steady barometer I did find the altimeter to be dead on accurate for an ascent/decent. Other than that I usually just use it as a guide.

One thing worth mentioning for watches in general are that it's wise to note the time elapsed since your last landmark and when you expect to see the next one. Either keep track using the time function or the stopwatch. If you know your usual pace for the terrain/elev change, you can estimate with some accuracy when you should come across the next landmark. This is an important mental habit when hiking in areas that are not well marked - it can give you a sense of when to backtrack to see if you've missed a turn. It also heightens your senses to watch out for such turns and landmarks, reducing your chances of missing them in the first place.


Yes to all but especially to that last paragraph. It's called dead reckoning. Everyone does it to some extent. But a very worthwhile skill to develop and utilize. Best to anticipate landmarks and waypoints rather than be surprised by them.

Also: keep a running down-counter from your last blaze sighting. Most of the time on the AT, you should be seeing a blaze every few minutes.

Dogwood
03-31-2017, 12:08
How many sensors does your $50 altitude watch employ? What degree of accuracy do you require for the unit?

Berserker
03-31-2017, 12:35
I use a Highgear altimeter with the integrated caribiner, and hook it to a D ring on the shoulder strap of my pack. I find it to be something fun to use, and it's great for pacing myself on ascents.


I use a different brand of altimeter ... but they have to be reset at every opportunity.
I concur, frequent calibration keeps it more accurate. I do this by fixing the elevation when I get to an elevation that I can read easily off of a map.


For hiking, I prefer an altimeter watch that hangs on a cabiner rather than my wrist. I leave it hanging off a d ring on my shoulder strap. Flip it up when I want to look at it.
Amen brother...can't stand something attached to my wrist.

Puddlefish
03-31-2017, 13:53
I strapped my watch to my hiking pole upside down. The temperature function was more accurate away from my body. Functioned as a "wall clock" when it held up my tent. The altimeter was surprisingly accurate for the first month of the trail, but the weather was consistently good. Then it broke, probably got vibrated to death on the pole.

rafe
03-31-2017, 16:00
Here's the report from a half day of skiing with this thing. The main lift has an official vertical of 1000 feet. The Casio measured 995 feet almost every single run. At least seven or eight runs in a row. One run it was five feet over. Another, it was five feet under. So, it's extremely accurate and repeatable for differential measurements like that.

Displayed elevations all drifted slowly upward about 45-50 feet over the course of five hours. That's mostly consistent with a drop of about 0.06.-0.07 inches of mercury (barometric pressure drop) over the same period, according to Weather Underground.

Miner
03-31-2017, 16:27
As some have noted, the temperature on a wrist watch isn't accurate as the body heat influences it to read higher. Having it hanging on my pack gives a much more accurate reading though having it in direct sunlight for awhile still can make it read a bit higher.

AfterParty
03-31-2017, 16:55
I would guess it just takes a utm grid plots it and determine elevation based on the grid.

Time Zone
02-21-2019, 00:13
Just an update. I got just shy of 3 years out of my Casio's first battery.
After replacing the battery, it worked as new for 5 weeks. Then, the buttons locked out all functions. The watch still kept time fine ... the buttons pressed in and sprang out fine - just nothing happens anymore. A few others on the River Site report this strange behavior too.
Looking around, it's still the best option for me. I don't need great accuracy for altimeter or barometer. Good is good enough for me. I don't use the thermometer at all. The other functions that it has that I value (over say a super cheapie Casio Illuminator) are the stopwatch* , the alarms, the time zones, and the countdown timer. I have my own separate compass. So for my needs, it's hard to beat at $40.

*my super cheapie rolls over the stopwatch after 59m 59s ... it does not keep track of hours! I didn't notice that when I bought it; I probably never thought it would be so limited. Ironically it keeps time a bit better than the $40 twin-sensor Casio.