Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation: Dirthugger's Avatar
    Join Date
    Mar 2007
    Posts
    308

    Is this normal??

    Just acquired the Oregon 450, so far I'm quite happy and satisfied with the features based on my needs. However, it is doing something that I'm not sure if it's normal. I already sent an email to Garmin support but still haven't received a reply. It is in regards to the Elevation data code in the Trip Computer. The elevation data keeps fluctuating ie:318,319,310 and so forth. This is occurring with the unit sitting idle on my desk. Due to this it is also affects the traveled distance data. I will take a short video to share with you guys since I sound vague about the issue or non-issue. Hopefully it is just a setting I need to change. I have tried calibrating the Elevation and tried the different settings but still same result.
    Btw, the software is current. ver5. and ver5.50

  2. #2
    Rep Power: Infinity
    Reputation: NateHawk's Avatar
    Join Date
    Dec 2003
    Posts
    11,907
    Quote Originally Posted by Dirthugger View Post
    Just acquired the Oregon 450, so far I'm quite happy and satisfied with the features based on my needs. However, it is doing something that I'm not sure if it's normal. I already sent an email to Garmin support but still haven't received a reply. It is in regards to the Elevation data code in the Trip Computer. The elevation data keeps fluctuating ie:318,319,310 and so forth. This is occurring with the unit sitting idle on my desk. Due to this it is also affects the traveled distance data. I will take a short video to share with you guys since I sound vague about the issue or non-issue. Hopefully it is just a setting I need to change. I have tried calibrating the Elevation and tried the different settings but still same result.
    Btw, the software is current. ver5. and ver5.50
    Pretty standard.

    There are little micro variations in air pressure, especially if there's a breeze.

    How's this for odd? High precision scales will fluctuate like that if there's a breeze. My small scale goes to 0.1g and it will fluctuate by 0.1g or so + or - if there's a stiff breeze through the room. The really high precision laboratory models have enclosures around them to keep the breeze from affecting the scale because breathing over them can cause them to fluctuate.

    Also, temperature change can cause some drift. I think there is a thermometer buried in the Garmin hardware so the barometer can account for this, but I'm not totally sure about the Oregon. I am not sure how good it is at reducing this error.

  3. #3
    mtbr member
    Reputation: erginguney's Avatar
    Join Date
    Dec 2005
    Posts
    953
    One way for GPS manufacturers to avoid this kind of customer confusion would be to not show elevation at such a fine granularity in the first place. I use a sports watch with an altimeter that shows elevation only in multiples of 10 feet, which sounds perfectly reasonable to me. I don't know why some others show a reading down to 1 foot. It's questionable whether the altimeters in these things have the astounding accuracy that would be necessary to accurately show anything more precise than +/- 10 feet anyway. Plus, even if you can, it will still be fooled by something as simple as the gentlest wind and look bad to the user, as it might be happening in this particular case.
    Looking for local rides? You'll find plenty on my website: Bay Area Mountain Bike Rides.

  4. #4
    Rep Power: Infinity
    Reputation: NateHawk's Avatar
    Join Date
    Dec 2003
    Posts
    11,907
    Quote Originally Posted by erginguney View Post
    One way for GPS manufacturers to avoid this kind of customer confusion would be to not show elevation at such a fine granularity in the first place. I use a sports watch with an altimeter that shows elevation only in multiples of 10 feet, which sounds perfectly reasonable to me. I don't know why some others show a reading down to 1 foot. It's questionable whether the altimeters in these things have the astounding accuracy that would be necessary to accurately show anything more precise than +/- 10 feet anyway. Plus, even if you can, it will still be fooled by something as simple as the gentlest wind and look bad to the user, as it might be happening in this particular case.
    I absolutely agree

  5. #5
    Explore More
    Reputation: DesertDog's Avatar
    Join Date
    Apr 2006
    Posts
    391
    Regardless of whether you use the altimeter for elevation basis or base elevation off of GPS satellite positions (there are device settings that allow you to choose), you will see those elevation fluctuations. Just the way it is!

  6. #6
    Goats Rule!
    Reputation:
    Join Date
    Sep 2007
    Posts
    306
    I experienced the same elevation reading issue when I had a 450. Sold it and never looked back. That wasn't the only reason I sold it though, there were other things I didn't like about it.

    My Vista HCx and eTrex 30 don't do the elevation change thing...of course, the 30 says my total elevation gain is higher than other units by a few hundred feet at the end of a ride. Go figure.

  7. #7
    mtbr member
    Reputation: erginguney's Avatar
    Join Date
    Dec 2005
    Posts
    953
    Quote Originally Posted by KingOfTheHill View Post
    of course, the 30 says my total elevation gain is higher than other units by a few hundred feet at the end of a ride. Go figure.
    Not surprising for a unit that uses a barometric altimeter, if that's what it has. Since it measures elevation based on air pressure and since air pressure changes due to more than just elevation (it also changes due to weather conditions), it's not abnormal for it to skew over the course of the few hours of a ride due to the approach of a higher or lower pressure air mass.
    Looking for local rides? You'll find plenty on my website: Bay Area Mountain Bike Rides.

  8. #8
    KLF
    KLF is offline
    mtbr member
    Reputation:
    Join Date
    Apr 2007
    Posts
    116
    Quote Originally Posted by Dirthugger View Post
    Due to this it is also affects the traveled distance data.
    Not true. GPS distance is equivalent to what would be measured on a map. Elevation changes are irrelevant.

  9. #9
    Rep Power: Infinity
    Reputation: NateHawk's Avatar
    Join Date
    Dec 2003
    Posts
    11,907
    Quote Originally Posted by KLF View Post
    Not true. GPS distance is equivalent to what would be measured on a map. Elevation changes are irrelevant.
    I think what he was referring to was the fact that even though the gps is stationary, it still accumulates distance traveled. After thinking on it a bit, this is just how handhelds work. The gps itself does not calculate stopped time, or have an autopause function. Those calculations are done after the fact in whatever software you use for analysis. Topofusion does it with data from my Oregon. This is not associated with the altimeter issue.

  10. #10
    KLF
    KLF is offline
    mtbr member
    Reputation:
    Join Date
    Apr 2007
    Posts
    116
    Quote Originally Posted by NateHawk View Post
    I think what he was referring to was the fact that even though the gps is stationary, it still accumulates distance traveled. After thinking on it a bit, this is just how handhelds work. The gps itself does not calculate stopped time, or have an autopause function. Those calculations are done after the fact in whatever software you use for analysis. Topofusion does it with data from my Oregon. This is not associated with the altimeter issue.
    That wasn't how I read it.
    The elevation data keeps fluctuating ie:318,319,310 and so forth. This is occurring with the unit sitting idle on my desk. Due to this it is also affects the traveled distance data.
    But, yes, it is normal for a stationary GPS to "wander" and the resulting spider web is readily visible using Topofusion or any similar software, especially if the track recording is done using a timed interval.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •