Inaccurate lap times

[k3sk]

Hi,

I am considering buying the Pool Swimming plugin. I use Garmin 910XT. However, I have noticed, that lap times and total times are different from those ones imported to Garmin Connect or directly read on watches.
I am not sure what is causing inaccuracy, because I use Pool Swimming plugin together with Garmin FIT Devices plugin. However, even if I import data via default SportTracks plugin, the Pool Swimming plugin shows wrong times:

SwimmingPool.png (22.99 KiB) Viewed 45935 times

The Garmin Connect shows the following:

GarminConnect.png (11.5 KiB) Viewed 45935 times

When I import data via Garmin FIT Devices plugin, I see the following lap times (wrong as in Pool Swimming view) in activity's Split View:

Splits_garmin_fit_import_pluging.png (15.85 KiB) Viewed 45935 times

You can see the suspicious times in the first column - all with .86 in decimal places.

I will continue in a next post, because only 3 attachments are allowed for the post...

[k3sk]

...continued

When I import data via SportTracks plugin, I can see the correct times in Split View:

Splits_default_import_pluging.png (13.57 KiB) Viewed 45934 times

But in Swimming Pool view I still see incorrect times (the same as in the above SwimmingPool.png picture).

Am I missing something or is it a bug?
If you need fit file for testing, I can send it to you off list.

Thank you.

Peter

P.S. I use the latest 3.0.5004 versions of your plugins and SportTracks 3.1.5024.

[old_man_biking]

First of all, you observe DIFFERENT times, not necessarily incorrect ones
Could you please attach the .FIT file of this swim and I'll have a look.

Cheers,
OMB

[k3sk]

Hi OMB,

I've sent you the file in PM.

Thank you,

Peter

[old_man_biking]

Got your file, but I don't understand your problem.
Let's take internal no. 2. It consists of 2 lengths with 1:06.0 and 1:02.8 duration.
Pool Swimming plugin shows 2:08.8 for the interval which is the correct sum of the 2 lengths. In fact PS plugin always sums up lengths to get interval durations.
GC shows the same length durations but an interval duration of 2:09.3.
Which to my best knowledge differs from the sum of the 2 lengths.

So I clearly see that PS plugin shows DIFFERENT values compared to GC.
But I'd say that PS plugin follows common rules of mathematics, GC obviously not.
Try it for other intervals - GC behaves similarly strange for these.

Cheers,
OMB

[Tisztul_A_Visztula]

GC is shit. I always promote ST3 and some of its plugins on forums.garmin.com, because some of the complaints there have nothing to do with the hardwares or the unit firmware, just simply related to GC. I am not surprised at all that now I faced another example.

[Burnt Toast]

GC is shit. I always promote ST3 and some of its plugins on forums.garmin.com, because some of the complaints there have nothing to do with the hardwares or the unit firmware, just simply related to GC. I am not surprised at all that now I faced another example.

On that note, it amazes me that a lot of people take what GC spits out as "gospel" and is the ultimate answer. If GC says so, it must be true.

[old_man_biking]

It's a general mechanism in human minds.
Whatever you see first, and probably presented by a "reliable authority", is taken as the one and only undoubted truth.
Whatever doesn't fit into that scheme is likely to be ignored or considered as "wrong".
The old saying: "It's in the newspaper, it is true!".
It takes an effort to overcome this bias. Some people habitually question "the truth" and find it easy to overcome it. Others don't even have a faint idea that "the truth" could sometimes not be true.

Cheers,
OMB

[texmurphy]

Are we still talking about immersion in water?

[old_man_biking]

42

[Tisztul_A_Visztula]

The answer arrived too late for poor Douglas.

[k3sk]

Hi,

I am sorry, but I am afraid that you didn't understand what I was talking about.

I am not taking GC as a source of true. But the GC shows the same values as they are displayed directly on 910XT when I review my training.
Furthermore if I use SportTracks without any plugin (i.e. without Pool Swimming and Garmin FIT Devices plugin), I get the same values as they are in watches as well as in GC. It means that Pool Swimming is showing other values and I want to understand why. Sometimes the differences are even several seconds.

Further point is inconsistency between Pool Swimming values and values shown in Sport's Tracker's Splits view:

PoolSwimmming versus splits.png (26.17 KiB) Viewed 45837 times

Just compare the column "Split time" on the left and "Time" on the right.

Now I am in a hurry, I'll get back to you in the evening.

Kind regards,

Peter

[old_man_biking]

I understood your post - but you possibly didn't read mine carefully. Maybe you were in a hurry
Please re-read viewtopic.php?f=110&t=15338#p81116 .
All you need to understand is in there.

Cheers,
OMB

[k3sk]

Hi OMB,

I did read your post carefully and understood it. I appreciate it, but it didn't reply to my questions.

I will try to summarize all my findings:
1. Pool Swimming plugin shows length intervals almost correctly, except the fact that the values are not rounded properly (decimal digits are only trimmed) and this has confused me (e.g. value 70.099 is shown as 70.0 instead 70.1):
e.g. if we take the 1st lap instead of the 2nd one we get the following:
length 1: 00:01:11.0
length 2: 00:01:05.3
Total shown in PS is 00:02:16.4 and this is not following common rules of mathematics That's why I think you have chosen the second lap for your explanation

2. However, confusing is the lap time. I have inspected the FIT file using FitSDK and it has revealed, that the lap time present in the FIT file is not a sum of length intervals. Now the question is, why? Is it a firmware bug? What value is authoritative for 100m swimming (2 lengths)?

910XT_values.jpg (35.37 KiB) Viewed 45815 times

3. When I use SportTracks without OMB plugins I get different results in Split view than with OMB plugins.

4. When I use SportTracks with OMB plugins, I get non matching results between PS view and Split view (as it was shown in "PoolSwimmming versus splits.png" screenshot). Furthermore, the Split view has the 1st column (Time) values always ending with .86. Isn't it suspicious? I don't believe I swam all laps exactly with .00 times. This behavior is visible only when I use OMB plugins.

5. I have noticed also another strange thing in PS view - in the upper view I cannot see more than 53 lengths even if I use zoom out tool. I cannot even move the view to the left to see lengths beyond length 53:

MissingLengthsInPS.png (45 KiB) Viewed 45815 times

What I am looking for is an application which can precisely store my results and allow me to analyze them. The application which I can rely on. I consider a Pool Swimming plugin a nice piece of software but some inconsistencies prevent me to fully rely on it.

Kind regards,

Peter

[k3sk]

GC is shit. I always promote ST3 and some of its plugins on forums.garmin.com, because some of the complaints there have nothing to do with the hardwares or the unit firmware, just simply related to GC. I am not surprised at all that now I faced another example.

On that note, it amazes me that a lot of people take what GC spits out as "gospel" and is the ultimate answer. If GC says so, it must be true.

I don't consider GC to be a great tool, but in this case it is showing the very same values as shown in Garmin 910XT:

910XT_values.jpg (35.37 KiB) Viewed 45814 times

If you doubt about GC, then you must doubt about 910XT in this case, too. And if we doubt about 910XT itself, we cannot believe ST3 results anymore because they are imported from 910XT

In no manner I mean that 910XT is without bugs. What I am trying to find out here is what values I can rely on.

[Tisztul_A_Visztula]

"If you doubt about GC, then you must doubt about 910XT in this case, too. And if we doubt about 910XT itself, we cannot believe ST3 results anymore because they are imported from 910XT "

I must admit that you are right with your reasoning. The only hope is that some of the plugin developers understand how one should interpret the eventual strange behaviour of some gadgets and some of these bugs can be handled, as it happened in PS plugin regarding separating resting periods and active laps logged by 910xt independently of the user habits. I mean some users simply use Lap button, some Lap&Start/Stop buttons at the end of the intervals.

[texmurphy]

...If you doubt about GC, then you must doubt about 910XT in this case, too. And if we doubt about 910XT itself, we cannot believe ST3 results anymore because they are imported from 910XT
In no manner I mean that 910XT is without bugs. What I am trying to find out here is what values I can rely on.

Garmin Connect will always report the value from their devices for lap times from the lap summary values. GC does not recompute these values whereas ST will.

[k3sk]

Garmin Connect will always report the value from their devices for lap times from the lap summary values. GC does not recompute these values whereas ST will.

It depends... If I use clean ST3.1 installation and its built-in SportTracks Garmin GPS Plugin for import, I get the same results as in GC.
ST3.1 shows the following:

ST_no_plugin.png (46.37 KiB) Viewed 45807 times

GC shows the following:

GC_laps.png (11.4 KiB) Viewed 45807 times

The results are the same if we take into account GC's correct rounding.

[texmurphy]

In this instance you are using "Recorded Values", which are the summary data from the Garmin device.
My point is that GC will always say what the device says. This is the main reason that most users will believe the "truth" in GC/device recording and discount any other analytic program (ST/Strava/GoldenCheetah/...) as being likely wrong.

It's a general mechanism in human minds.
Whatever you see first, and probably presented by a "reliable authority", is taken as the one and only undoubted truth...

[old_man_biking]

Hi OMB,

I did read your post carefully and understood it. I appreciate it, but it didn't reply to my questions.

I will try to summarize all my findings:
1. Pool Swimming plugin shows length intervals almost correctly, except the fact that the values are not rounded properly (decimal digits are only trimmed) and this has confused me (e.g. value 70.099 is shown as 70.0 instead 70.1):
e.g. if we take the 1st lap instead of the 2nd one we get the following:
length 1: 00:01:11.0
length 2: 00:01:05.3
Total shown in PS is 00:02:16.4 and this is not following common rules of mathematics That's why I think you have chosen the second lap for your explanation

2. However, confusing is the lap time. I have inspected the FIT file using FitSDK and it has revealed, that the lap time present in the FIT file is not a sum of length intervals. Now the question is, why? Is it a firmware bug? What value is authoritative for 100m swimming (2 lengths)?

3. When I use SportTracks without OMB plugins I get different results in Split view than with OMB plugins.

4. When I use SportTracks with OMB plugins, I get non matching results between PS view and Split view (as it was shown in "PoolSwimmming versus splits.png" screenshot). Furthermore, the Split view has the 1st column (Time) values always ending with .86. Isn't it suspicious? I don't believe I swam all laps exactly with .00 times. This behavior is visible only when I use OMB plugins.

5. I have noticed also another strange thing in PS view - in the upper view I cannot see more than 53 lengths even if I use zoom out tool. I cannot even move the view to the left to see lengths beyond length 53:

What I am looking for is an application which can precisely store my results and allow me to analyze them. The application which I can rely on. I consider a Pool Swimming plugin a nice piece of software but some inconsistencies prevent me to fully rely on it.

Kind regards,

Peter

Re 1: PS plugin rounds to 1/10 sec. So if lenght 1 is in fact 1:11.04 and lenght 2 is 1:05.34, the sum is 2:16:38 which is rounded to 2:16.4. That's maths.
And you're right: I've choosen lap 2, because you need less maths to understand it and I didn't want to write the explanation in the previous line. No I had to
Re 2: Ask Garmin. I'm not talking about right or wrong, but about useful. And I consider it more useful to consider the interval and activity times as rollups and simply sum up the constituent times. The values presented by the Garmin device and GC confuse me a bit.
Besidess, I wanted to avoid that users write piercing posts, asking me why the interval durations differ from the sum of the length durations
Re 5: If you encounter such problems, please post and attach the affected .FIT file.

Cheers,
OMB

[k3sk]

Hi OMB,

Re 1: PS plugin rounds to 1/10 sec. So if lenght 1 is in fact 1:11.04 and lenght 2 is 1:05.34, the sum is 2:16:38 which is rounded to 2:16.4. That's maths.
And you're right: I've choosen lap 2, because you need less maths to understand it and I didn't want to write the explanation in the previous line. No I had to

I am sorry, but I cannot agree here with your math. I don't know where do you have the values 1:11.04 and 1:05.34 from, but FIT file contains different values.
Here are the values for the first 8 lengths present in the FIT file:

FIT_contents.png (8.92 KiB) Viewed 45758 times

Also watches show the same values properly (although rounded to 2 decimal points):

Length1.jpg (33.34 KiB) Viewed 45758 times

As you can see, the length 1 has time 1:11.062 and correct rounding to 1 decimal place should show 1:11.1. However, PS shows 1:11.0. If you look at all other lengths you can see, that neither the length values nor their sums (interval totals) are rounded correctly in PS. The decimal numbers are simply stripped instead of rounding.

PS_8_lengths.png (17.72 KiB) Viewed 45758 times

Interval 2 total in PS is shown as 2:08.8, but it should be 2:08.9, because the sum was 2:08.874.
The most visible inaccuracy in PS is shown in Interval 3, where the sum of lengths is 2:06.999, but PS shows it as 2:06.9. It means inaccuracy of almost 0.1 second.

Re 5: If you encounter such problems, please post and attach the affected .FIT file.

In fact, I see this problem in all my trainings. The .FIT file I sent you already on Oct 31 also shows the same problem.
Just a hint - the problem may be caused by Windows display font size - I use the default "Smaller - 100% (default)".

Kind regards,

Peter

[k3sk]

Hi OMB,

Have you had a time to review my last post, please?
If you need further illustrations, just let me know.

Do you plan to fix these bugs, please?

Thank you.

Best regards,

Peter

[old_man_biking]

Sorry, but I didn't find the time to look into it.

EDITED:
I just spent the time to read your post.
Re "I don't know where do you have the values 1:11.04 and 1:05.34 from":
I just made up these numbers to illustrate how rounding can provide results that are on 1st sight strange.

It seems that the date/time formatting functions do not round but simply cut off, so the 1/10 second might be wrong.
But please give that a 2nd thought: are you sure that your Garmin device records your turn with the precision of few 1/100 seconds?
I'd guess that you're lucky, if it's exact to a few 1/10 seconds.

I won't look into this issue any further.

Cheers,
OMB

[k3sk]

Hi OMB,

1. So finally you admit, that it was your math what was wrong. It took me a lot of time to explain you such a trivial thing.
Garmin 910XT has time measuring precision in Swim mode of 1/16 sec.

2. I have reported another bug - your plugin doesn't display all swum lengths - I have already sent you the FIT file before.

Furthermore, yesterday I discovered another bugs in length times and they don't allow me to analyze my swimming workouts at all.
It's a pitty that you are not willing to fix such simple bugs
Knowing that I regretted that I bought your plugins just yesterday
Is it possible to deactivate my license for the bought plugings and return my money back?

Regards,

Peter

[old_man_biking]

Plesse send me a pm with the invoice Id, confirm that you have uninstalled the plugin and won't use it anymore and I'll return the PayPal payment.
OMB