Been wondering if I should take out two phones on a ride to test the differences in GPS signal and therefore times on segments. Anybody done that or take out a garmin and a phone to record a ride? Did you or do you see any discrepancies?
So basically your asking which device makes you look faster 🙂
I did this with Garmin, Garmin watch and phone over the years. Not for segment times (whatever, I know I am slow!), but to see the spread in the data on the recorded ascent (I am a scientist, what can I say....). Garmin vivoactive watch certainly gives the lowest total ascent. Garmin 800 gives the most consistent results on the same rides. Phone....havent tried it for a while, but when I did a while back fit with the garmin wasn't too far off, but more likely to risk loosing signal = dubious results. Make sense, bigger receiver in dedicated GPS will always be more accurate.
My Garmin lasts longer and I can stop start for uplift easily. Saves my phone getting wet?
That sort of test?
Yes I did this. It was a bit of a pain as I had to create an additional Strava account for the purpose.
I tried 2 Android devices, a Sony Experia T and a Motorla Moto G mk1.
They were both put in the camelbak and left there. I went for a ride on one of my usual loops of about 20 miles.
They both returned similar results, the biggest discrepancy was about 2s that I saw.
Android app and non barometric Garmin rely on Strava data and usually record less altitude than a baro Garmin where Strava takes the data off that device.
Latterly, me with app & mates with Garmin barometric, I get a much (15%) lower moving average. The autopause works differently it seems. Concurrently the altitude now seems more on a par.
So different devices = sometimes vastly different numbers in my experience.
my old iPhone was pretty "generous" 😆
take two phones if you want, but apart from the difference that they will inevitably have, what will you have learned? You still don't know which one is more accurate. Will you?
I did this on one ride with an iPhone and a Garmin. iPhone tracked just as precisely but tended to give very slightly shorter segment times and the interface is easier so the Garmin was retired.
The autopause works differently it seems. Concurrently the altitude now seems more on a par.
Autopsies is probably the most pointless feature especially as Strava reports moving tine
the biggest issue with the strava app is that it records GPS at 3-4s intervals.
most garmins now are every 1s.
before I got an 520, i used the wahoo fitness app that records GPS at 1s intervals and it was comparable to the garmin.
Strava - anyone here experimented with different devices?
Yes frequently. Have Garmin Forerunner and 2 iPhones and the iPhones are way more reliable the Garmin has a habit of straightlining even with the GPS sensitivity in Turbo mode. The best thing I can say about it is that it's repeatably inaccurate.
I did this on [s]one [/s]several rides with an iPhone and a Garmin. iPhone tracked just as precisely but tended to give very slightly [s]shorter [/s] longer segment times
so there, not even consistent between users!
My Garmin also consistently reads -10% elevation compared to my iPhone and my friends Garmins on the same ride.
I still use the Garmin in preference as more robust, easier to bar mount, battery lasts longer etc.
Might as well just stick to the same device as you're only ever going to be comparing against yourself so better to keep it consistent.
I've used Garmin Edge 205 versus iPhone and found the iPhone gives me slightly "better" times - ie. shorter times for segments. Probably due to lower accuracy of 3-4 s data intervals versus 1 s on the Garmin.
Likewise, my old as the hills Garmin 205 is more accurate than my brand spanking new Garmin 25 as the 205 has the facility for 1s recording and the 25 only does "smart" recording.
There was a website (forgot which now) which let you look at strava data in detail, so for a segment you could see where each riders start and end point were.
The start and end are chosen as the nearest recorded point, not an exact point or an average between 2 points, so shorter segments and inaccurate devices (phones or cheaper GPS, or GPS set to 'smart' recording) are more likely to have a point further from the actual start, so could have recorded a slightly longer or shorter segment than others.
[b]EDIT: [url= http://blog.veloviewer.com/41mph-the-evidence-against-the-sunday-times-article/ ]This [/url]explains it better.[/b]
Some older garmins don't pick up Glonass, whereas most newer ones do, as do many newer phones. Accuracy may be different between units depending on weather conditons, especially moisture content of atmosphere, and tree/building cover. Some units cope with the interference better. Design of the units down to aerial placement in the case may have an effect too.
Most Accurate isn't the same as fastest.
Tbh with most modern gps whether in a phone or in a standalone I'd expect time for most strava segments to be within margins of error, and if you want faster times then HTFU rather than spending time worrying if using an iPhone will get you up Box Hill faster than Alex Dowsett.
My latest phone just gave me a KOM on a 35 second segment. That's the kind of 'accuracy' I'm going for.
"The biggest issue with the strava app is that it records GPS at 3-4s intervals."
When I've opened the gpx file its always recorded a GPS position every 1000ms for my devices, unless paused.
[quote=kiksy ]
When I've opened the gpx file its always recorded a GPS position every 1000ms for my devices, unless paused.
maybe it's updated now but the strava iphone & android app always used to record at 3-4 second intervals and then match nearest points to the start/finish of segments.
so if you got lucky, you could gain 3 seconds at the start and 3 seconds at the end of a segment.
maybe it's updated now but the strava iphone & android app always used to record at 3-4 second intervals and then match nearest points to the start/finish of segments.
It's possible its dependent on phone hardware. If the GPS only updates every 2000ms, thats what the app has to use.
Yes 😀So basically your asking which device makes you look faster
Well in a way no, im looking for the most accurate device. The last few rides have missed a segment or been widely out on some.
Interesting reading on some of those links tenacious_doug. I think popping my phone in the bag rather than my pocket could help. I may just buy a garmin though as it could be my 4yr old phone reaching the end of its wonderful life.
Did this once (Garmin 500 & Galaxy S3) on a ride following a Facebook conversation. Totally inconsistent as the list of segment times below shows (IIRC it's Garmin first, phone second).
2:01 / 2:00
1:50 / 2:10
13:51 / 12:13
12:49 / 13:04
12:49 / 12:46
4:00 / 2:11
1:34 / 1:35
1:23 / 1:26
1:22 / 1:13
0:35 / 0:39
0:49 / 0:49
6:24 / 6:14
0:38 / 0:33
2:45 / 2:49
14:24 / 12:47
I often find the Garmin (non-GLONASS) loses its way under heavy tree cover. Often I'll ride the same short loop 2 or 3 times on a ride and one of the loops will be accurately recorded in terms of length and shape, but will be offset from the others by about 20 or 30 metres.
My Garmin 800 is much more accurate on altitude gain and much more likely to pick up a Strava segment than my mobile.
When I forget it and use my phone it seems to miss about 30 to 40% of segments.
I find the Garmin very useful for other reasons too.
I've got a Garmin Forerunner watch and an edge 520. Did two wiggly rides last week in the woods under tree cover. On both occasions the Forerunner recorded the total distance as 500m further than the edge. It seemed to me that the edge was straightlining so not picking up the wiggles, despite both devices being on 1sec recording. The autopause on the edge was also under suspicion so I turned it off on the second ride.
Finally went on a road ride, which was a more straight than wiggly route, no tree cover, and the edge measured further
I took 2 phones out once (logged into same account) and got a 6s difference on one segment.
I've also overtaken a mate on a segment before and he's posted a quicker time (with his dodgy iPhone).
Not worth getting hung up on
My old forerunner 305 gives a lot less elevation than a phone or newer Garmin.
Anecdata rocks