Total Ascent Values Exaggerated by 50% [Bug 29]

[JungleJim]

whether it's the old version or the new version, the altitude at home when I turn on the 67 is always the same and is the correct altitude. I didn't notice any big differences between that of the 67 and the reality on the ground.

It's not the elevation readings that are problematic. It's the way the devices calculates Total Ascent and Total Descent that's an issue. The elevation reported by my device during activities (esp. after calibrating the altimeter) has always been quite accurate within the tolerance as specified by Garmin.

[mimichris]

I have never noticed such a difference in my cumulative ascents, to see it I use the DEMs from IGN France precise to 5m (squares of 5m x 5m) in the field, my Twonav software allows me to recalculate the ascent cumulative and I do the calculation there is little difference with that of 67 and that of the DEM.

[JungleJim]

I have never noticed such a difference in my cumulative ascents, to see it I use the DEMs from IGN France precise to 5m (squares of 5m x 5m) in the field, my Twonav software allows me to recalculate the ascent cumulative and I do the calculation there is little difference with that of 67 and that of the DEM.

What setting do you use for Altimeter > Auto Calibration on the GPSMAP 67? And how often do you calibrate the altimeter?
And in what way do you read the cumulative ascents? Based on the Total Ascent data field, or the ascent in the activity summary page?

Lot of questions but I'm interested in what could make your readings more accurate than that of others.

[Backstreetbob]

As anyone noticed any different with the new firmware update?

[RunnerAndrew]

Hi everyone , I have also found over the last year my Garmin GPSMap67 ascent / descent data displayed tended to be double what it should be.
It has never really bothered me personally, my main reason for getting the device is for accurate navigation and a great battery life which the device does very well.
I do like to look at my current height data from time to time and again this is very accurate , it has only been the ascent and descent that have been incorrect.
Garmin recently advised me to test with auto calibration to once rather than continuous that I had been using.
I have only just had a chance to test today on a regular 13mile run that I do.
According to various map app sources the ascent and descent for my 13 mile run should be around 1152 feet, looking back at my last few GPSMap67 recording the ascent and descent was recorded at 2864 feet.
On my run today with new firmware 8.30 , altimeter set to calibrate once , I also manually calibrated before I started , my ascent data recorded today was1194 feet.
I am not sure if the new firmware 8.30 is what has given me this much more accurate ascent reading or if it has been by changing altimeter to the only the once calibration setting.
I will continue to monitor on my next runs on the same route.

[JungleJim]

As anyone noticed any different with the new firmware update?

Haven't been able to test extensively yet. A first walk with 8.30 did show better Total Ascent/Descent values with Auto Calibration to Once, but since it's only a single test no conclusions should be drawn from it in my opinion.

[Domi93CH]

What do you mean by better values? For me (4.70) I have several times too much total ascent/descent on flat terrain. As soon as someone here can confirm that these values ​​are now accurate, I will update it to 8.30.

However, even after a one-time calibration I still got values ​​that were far too high.

[JungleJim]

Earlier tests with 7.60 on a quite flat hike around sea level led to Total Ascent values of 70-80m. The same hike with 8.30 and Auto Calibration set to the same value as the earlier test (Once) led to Ascent value of 21m. But again as there are many variables this single test is not conclusive and no proof of anything having been fixed by Garmin.

[Domi93CH]

Then i think im not updating, or should I?

[JungleJim]

Then i think im not updating, or should I?

That's something only you yourself can decide!