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Hi All:
In the altimeter setting I get really skewed numbers (usually +200 feet) than my actual altitude above sea level. Right now I'm +78 feet and my watch is reading +320. I have set refererence altitudes, but the next day it seems to forget that and read incorrectly again. Anyone else have this issue and/or ideas?

Thanks in advance.
 

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Of the Riseman's special features, I only use the barometer to see where things are headed weatherwise. The altimeter always seems to think I am underwater. I've found to be more trouble than useful, so I ignore this feature now.
 

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My Pathfinder (PAW1300) altimeter does the same thing although the reading never seems to stray more than +/- 140 feet from my programmed reference altitude.
 

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so how should i adjust height if i do not know which is correct currently ( in case when riseman shows wrong results ) ?
Without a reliable source like google maps, google earth or a topo map, you simply can't.

cheers
 

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Mine is rarely correct even with reference altitude set. I think it gets it's reading from air pressure which is always changing.
 

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Only solution:
get a GPS-watch or handheld device. Altimeters that are based on air-pressure can never be 100% accurate.

Greetings, Sedi :)
 

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Only solution:
get a GPS-watch or handheld device. Altimeters that are based on air-pressure can never be 100% accurate.

Greetings, Sedi :)
I respectfully disagree ;-)

A GPS watch is often much more off than an airpressure based altimeter calculation. It all depends an movement, satellite vector, reception quality and number of satellites available. And while a handheld GPS is certainly a big plus in the field, a GPS watch is not sufficient with a few hours of runtime.

What is realy needed is an ABC watch with an altimeter lock, therefore altitude remains stable, no matter of weather drifts. Also a watch that can display sea-level-pressure is of great help, since this is the common standard for professionel weather stations. And if one knows the sea-level-pressure, he automatically has the correct altitude, so one thing less to worry about.

But GPS or not, ABC watch with alti lock and sea-level-pressure or not, the point is that NO casio is able to keep a fixed altitude for as long as the user wants, which makes the altimeters in basically any casio next to a useless gimmick.

cheers
 

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But GPS or not, ABC watch with alti lock and sea-level-pressure or not, the point is that NO casio is able to keep a fixed altitude for as long as the user wants, which makes the altimeters in basically any casio next to a useless gimmick.
Now it's my turn to disagree ;-). An ABC watch can mostly just be a back-up for other instruments. I think anybody who tries to do some serious mountaineering with just an ABC-watch as an instrument (alti-lock or no alti-lock) must be mad. You should at least have a topo map (if there are any for the region you're in) and compass - so you will have the ability to calibrate the altimeter once in a while which should be enough to get some useful data out of it.
I know that some think: "Why have an altimeter if I need to know my altitude in the first place to calibrate it?" - but even on watches with sea-level pressure you need to know either your altitude or the current sea-level pressure to calibrate it. But indeed - sea-level pressure is very useful (just got my X-Lander a few days ago and I love the sea-level pressure and the fact that altimeter and sea-level data influence each other - while absolute pressure stays unaffected - well, it has to of course). Alti-locks are useful, too but that doesn't mean all other ABCs which don't have it are "useless gimmicks".

Greetings, Sedi :)
 

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Now it's my turn to disagree ;-). An ABC watch can mostly just be a back-up for other instruments. I think anybody who tries to do some serious mountaineering with just an ABC-watch as an instrument (alti-lock or no alti-lock) must be mad. You should at least have a topo map (if there are any for the region you're in) and compass - so you will have the ability to calibrate the altimeter once in a while which should be enough to get some useful data out of it.
In theory this is all good and fine, however the gap between theory and practice is seldom a small one. Out in the wild it is not uncommon that navigating by altitude is sometimes a lot easier (or even the only choice) than navigating by bearings. I agree that a good topo map and a magnetic field compass should be in the backpack of any outdoorer, but I do not agree that you calibrate your ABC watch based on a topo map after you need it. When navitation by compass is not possible and the altimeter is the only instrument available, it needs to be as precise as possible. Only if you are 100% certain of your location (which is quite a challenge in the middle of nowhere) you have the luxury to recalibrate the altimeter should it be necessary and only then. I don't know if you have ever done an orientation run or something similar with only a compass, altimeter and (topo)map. If so, you should know how difficult this can be, if not I recommend to give it a try - a lot of fun and lots of things to learn, which pretty much seperates theory from practice.

Alti-locks are useful, too but that doesn't mean all other ABCs which don't have it are "useless gimmicks".
Well, let me rephrase it then. ABC's without Alti-lock and SLP are useless gimmicks for me - satisfied?

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Is more than 10 years of boy scouts enough practice:-d? It included a lot of hikes (of course it wasn't always necessary to use a compass - but I know how to use one in combination with a map). One more thing: an alti lock might be useful being in the same place (lets say over night) but what if you move up and down all the time? Won't an ABC watch even if it has an alti-lock go out of whack? I don't really see the point of an alti-lock if you're constantly on the move. The watch still doesn't "know" what the real altitude is. Of course it'll keep the readings more accurate over a longer period of time compared to a watch without alti-lock. But you could for example while resting take a look at the altimeter and write the value down - if it changes over night you can still recalibrate the altimeter. But I do admit that SLP is really very useful. Well I guess I'll get an ABC with an alti-lock anyway sooner or later - might well be the Tech4o or something similar.

Greetings, Sedi :)
 

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Sedi,

yes the Alti-lock is most useful if one stays at the same place and does want to ignore the possible weatherdrifts, I think that is what the thread starter was refering to. Most sophisticated ABC's have an automatic Alti-lock, meaning they detect very well, the difference between movement from place A to place B or the weatherdrift. That means whenever you stay for some time on the same location, the Alti-lock will kick in and ignore upcoming drifts. This works in about 90-95% of all cases pretty well, the rest 5-10% are heavily weather changes (like an incoming storm for instance) when the watch "mistakes" weather with movement. I don't know if there is currently any other brand with such a feature, but for this case Tech4o has build in a manual Alti-lock (it also has the automatic feature) which allows you to stay 100% accurate all the time, no matter what cavorts the weather might decide to do. It becomes tricky if you go for an hike and forget to unlock the alti-lock, because all of a sudden you are at - let's say - 800 meters, but the altimeter still shows 100 meters. Without sea-pressure-level you would be in trouble now, presuming you simply don't know you current altitude. What you can do now is to look at the sea-level-pressure log which is recorded hourly for the past 36 hours. You can now set the sea-pressure level that it was when you left your house for the hike - let's say - 3 hours ago. along with the measured current pressure and the sea-level-pressure you are back in business and get the altitude. Of course after three hours there will be probably some ups and/or downs in the air-pressure but still it is the closest what you can expect.


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"Tech4o ............also has the automatic feature"

It does? Which model? Not the Traileader Jet unless I am mistaken.
 

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you are mistaken ;-)


cheers
 

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What you can do now is to look at the sea-level-pressure log which is recorded hourly for the past 36 hours. You can now set the sea-pressure level that it was when you left your house for the hike - let's say - 3 hours ago. along with the measured current pressure and the sea-level-pressure you are back in business and get the altitude. Of course after three hours there will be probably some ups and/or downs in the air-pressure but still it is the closest what you can expect.
Hm, I guess you just know a lot more about ABCs than I do :-d:-!. Now I also see what the real advantage of SLP is. And I thought it just relieves you from calculating it in your head (given you know your current altitude) but there seems to be a little more to it. Great - now the Tech4o is definitely on my list - but I guess the Traileader 1 is sufficient for me - except for the heart-rate monitor and computer link it has the same features as the "pro" doesn't it?

Greetings, Sedi :)
 

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...but I guess the Traileader 1 is sufficient for me - except for the heart-rate monitor and computer link it has the same features as the "pro" doesn't it?
That is correct.

cheers
 
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