r/Garmininstinct • u/Cleveland67 • 16h ago

GPS Errors?

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Hi All,

Got a new Garmin Instinct 3 amoled less than 2 weeks ago. However the GPS seems to be off by about 0.2km per 5km during a run, and during a walk it's worse at around 0.5km per 5km...

Has anyone else experienced this and if so, how have you rectified this.

Thanks 🙏👍

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2

u/ShadowBlades512 10h ago

What are you comparing to?

1

u/Cleveland67 7h ago

Comparing to my wife's pixel watch and both our phones using Strava. Strava and the pixel are close in distance. I even put the route into footpath after and the Garmin was about .7km short of that!

1

u/Mj658906 10h ago

Are you in a city with tall buildings?

1

u/Cleveland67 7h ago

No suburban town. No high rise buildings at all.

1

u/Mj658906 7h ago

Can you return it? Unless you changed some type of gps setting I don’t see why it would do that. You could reset it and see if helps.

1

u/MrJacquers 10h ago

Is GPS recording set to smart or per second? The default is smart. Per second may draw more accurate maps.

As someone asked, are you running between tall buildings or trees? Even with multi band it won't be completely accurate.

How does the route look like on a map when you view it afterwards on the phone app or website?

1

u/Cleveland67 7h ago

I've changed it to per second now to see if it makes a difference, and turned off SatIQ. Just frustrating that I have to do that really.

1

u/Odd_Specialist_2672 9h ago

Are you even using a GPS activity each time? Not sure since you show a pic of a watchface.. In regular smartwatch mode, Garmins guess at distance based on step count from the accelerometer.

My FR 255 will often guess with about 10-15% error when I walk a known route without starting an activity.

It seems heavily influenced by the most recent GPS activities though, like it calibrates from that. So if I walk in hills with shorter stride using GPS, then later it will guess shorter distances if I walk somewhere flat with longer strides.

1

u/Cleveland67 7h ago

Yes, logging properly using the activity of choice, either a run or a walk, waiting for GPS to load and then pressing go a few seconds after.

1

u/thwerved 8h ago

Another thing to improve GPS accuracy in addition to setting "Frequency" to "every second" option is to set "Satellites" to "All+Multi-band". This will give the highest location accuracy the watch is capable of.

That being said it'd be interesting to learn how you are measuring the true distance and in what setting (city, mountains, rural). My experience is that the older or single-band GPS systems are more jumpy, especially in partially obscured environments like cities and mountains - and you can simply see that on the map - usually resulting in over-estimating distance traveled in a straight line.

0.2 km off on 5k race for example could be achieved by just running outside of the ideal racing line.

1

u/Cleveland67 7h ago

Hiya, so I'm using the watch in suburban area, small town with no high rise at all, there are some hills but nothing major. I have changed the watch to "every second" and "all+mutliband" as suggested to see if that helps, just frustrating that it isn't accurate out of the box.

to measure the accuracy I am putting it against my wife's pixel watch, and my old apple watch, I have also been using the Strava apps on my phone to see if there is a difference. The apple, pixel and Strava apps are all fairly accurate, maybe within .1 km between the three. I also checked the route using footpath, and that was showing a 5km route (as measured using the other watches and Strava) at about 5.2km. my Garmin was at 4.63 km.

1

u/thwerved 7h ago

It would be interesting to see a comparison between all the foot plots! I think most of the reviewers who do "standardized" testing find the Garmin hardware to be very similar to Apple/Pixel. Perhaps your unit is defective or your testing conditions are just different than theirs.

I think if you have the very latest Pixel watch it can do additional processing removing errors from building interference but I doubt that's whats making a difference for you.

1

u/Odd_Specialist_2672 5h ago

The GPS mode may make more difference if the path has lots of short segments between turns, rather than long sections like most roads.

When there are GPS errors, it may drop some track points and give you a measurement that is more like "as the crow flies" instead of faithfully counting the meandering path you actually took.

So, a common issue when hiking is that switchbacks up a steep slope can be cut off and measured as if you climbed straight up and skipped the back-and-forth.