When I first started using my 705 in December with version 2.5 software the elevation function was not accurrate. I e-mailed Garmin and they stated they were still working it out.

Today I completed a 60 mile ride in the hills and low and behold the Garmin reports I finished at the same elevation as I started. Overall the elevation data looks about right.

Does anyone know if the latest software 2.6 fixed the elevation function?

v2.6 had no elevation related fixes listed that were listed:

Changes made from version 2.50 to 2.60:
- Fixed occasional issue with Edge shutting down when scrolling through Saved Rides.
- Fixed occasional issue with Edge shutting down when Mode button was pressed while following a Course.
- Fixed issue where user could not change vertical zoom scale for a Course profile.
- Fixed a problem where indoor rides in History could slow down access to Where To? menu.
- Fixed issue with Advanced Workouts not showing up under Today when the workout is scheduled for the current day.
- Fixed issue where sometimes the most recent History would not be written out to XML until disconnecting and reconnecting USB.
- Corrected the Average Power value shown for Entire Ride in History.
- Removed filtering from power data stored in History files.
- Made some corrections to the Polish and Portuguese languages.


v2.5 is where there were some however:

Changes made from version 2.40 to 2.50:
- Implemented change to allow the user to access Map Setup option for tracks which will allow showing that track on a map, and what color to display it in.
- Added ability to set Off-Route Recalculation behavior in Routing menu. User can set it to Automatic, Off, or Prompted.
- Fixed issue with long routes shutting down.
- Fixed issue where Autopause and Start/Stop were not getting saved into the History files. This could also cause Courses created from this History to not register these times.
- Fixed issue where History files would occasionally not upload due to misaligned data.
- Fixed inaccurate elevation when moving to and from areas with distinctly different altitudes or atmospheric pressures.
- Fixed random elevation spike in the first few track points.
- Added the ability to delete tracks.
- Fixed issue where speed would drop to 0 going through turns.
- Fixed issue where viewing a Course on a map went to the wrong location.
- Fixed barometer initialization issues in situations where the unit is turned off and back on within 5 minutes in the same location.
- Fixed issue with Course List where actions could be applied to the wrong Course.
- Fixed issue where course guidance lines were drawn on top of roads.
- Fixed issue with repeated Autopausing when using a wheel sensor.
- Fixed issue with creating a Workout with Spanish language selected.
- Improved German translations.

The Edge uses a barometer to measure elevation. Thus it is subject to changes in barometric pressure. It has to be able to determine if a change in pressure is due to the unit changing elevation or pressure changing due to weather.

If you are on a long ride that starts and stops at the same location and the presseure changes a lot during that ride there is a very good chance the unit will not show the same start stop elevation. The complaint that many of us Edge users have is that there is no way for the user to tell the unit what the correct pressure and or elevation is. If we could do that then a lot of the issues would be resolved.

Sorry, you asked a simple question but I gave you got this!

Great comments on the elevation question. I have been doing most of my riding in the "flatlands" of Houston, Texas. When I first got my 705 there would be quite a difference in the start and stop elevations even though the weather was consistant and I was only going 20 miles.

I was pleasantly surprised to see on this 60 mile loop in hilly Longview, Tx that the start and stop elevations were the same. Thus, my question regarding elevation fixes.

Since I have found no function to "set' the elevation of a given location, I do wonder how you can adjust the elevation for the given weather. However, if it will provide me with relative data as it seemed to do on this latest 60 mile ride, I am happy.

How does 705 calibrate the elevation? Does it depend upon GPS elevation at the start of each ride?

I am pretty sure that the Edge uses only the barometer to calibrate itself. If it used the GPS I would think it would be a lot more accurate at startup than it is at times.

There are pitfalls with GPS elevation too. The military can disable this feature when the ever they want. I have read some posts about the accuracy of GPS elevation that say it is actually less accurate than barometer.

Regarded, I wish the Edge had a screen where we could tell it both the correct elevation and barometric pressure. This would solve most if not all of our problems.

I don't think it's using just the barometer for altitude because pressure can drift dramatically day to day and this would equate to different starting altitudes even though you're in the same place. I've noticed it's always pretty close actual starting altitude if given time to adjust.

Garmin's running line only uses GPS altitude which is lacking is precision (probably for the reasons you mentioned) and could mean huge jumps in recorded altitude. For example, the NYC Marathon is a relatively flat race with a total ascent around 700'. If I do a search on motionbased for the race, I see a variety of results. The most egregious is this one with a recorded gain of 12,000'. Another with only a 2,000' ascent. The problem I see is that any spiking in altitude has a huge hit on total recorded elevation and these spikes can occur anywhere there is poor GPS coverage.

I think the 705 tries to be clever and set the altitude at the beginning of a ride, but it's not always correct and still looking for a manual override.

I would agree that it would make sense that it uses the GPS at startup. What really makes me wounder is why is can be 100' +/- off sometimes at startup. Once a 3d fix is acquired it can get the elevation.

I have read a lot of posts on https://forums.motionbased.com/smf/index.php?board=86.0 where folks waited 30 miunutes and the elevation was still off.

As you and I have both said, some sort of manual calibration method would solve.

If it's depending upon GPS for initial elevation, than 100' isn't too bad. It seems that GPS elevation is derived differently than location, which could contribute to the variety of results. Without any calibration, you could see anywhere from 500-1000' differences in elevation over the course of just a day or two which is perfectly normally.

However, altitude drift like the picture below on a day with no pressure change can drive you nuts (this was an out and back route which took place in less than an hour)