Inaccurate technology little rant

[Alan Clifford]

Parsing the .sml (Suunto markup language) file from my dive computer seemed to be too straightforward!  There is a start time

<Header>
<DateTime>2015-05-06T12:47:00</DateTime>


and then depths and seconds offset

<Sample>
<Time>80</Time>
<Depth>6.4008</Depth>
</Sample>


All looking good until I noticed the start time was at the top of the minute.  ALL my dives seemed to have started at zero seconds.  So I guess it could be truncatiing up to 59 seconds off the dive start time - irritating when I'm trying to match the depth against my photographs.   Why do they do this - it must have been harder to zero the seconds than to just record the real start time.

[Alan Clifford]

Next up is the fact that, according to the manual, the dive computer is only accurate to within 1/3 metre but it records the depth to 4 decimal places - 1/10 of a millimetre.  This is verging on the insane.

[Phil Harvey]

I have seen these same problems elsewhere.  Many cameras record nonsensical EXIF sub-second values.  Usually 2 decimal places, but often the accuracy is 0.2 seconds or worse.  Very few cameras actually record a reliable sub-second time.

But 4 decimal places for depth is crazy.

- Phil

[Alan Clifford]

Did I mention that the dive log records the temperature in Kelvin

<TempAtStart>303.15</TempAtStart>

The depth now goes into the photos and comes out again on the photo's webpage

http://f16.eu/2014/scuba.December/tn/f200_2871.jpg.index.html

And having looked at some divelogs, I think I'll be able to make up for the logs always starting at zero seconds by making sure my camera and dive computer are synchronized and taking a photo when I reach the sea floor.

[Phil Harvey]

Ho ho ho!