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screenshot GPStest - online edit of handbook/survey/gps.htm

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Philip Sargent
2026-05-06 22:23:24 +01:00
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handbook/survey/gps.htm
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@@ -83,7 +83,7 @@ or a cairn, for example - we don't use paint any more) and place
the GPS on the point. Don't build a cairn, they don't last for decades and we have survey stations that provide permanent locations. Give the GPS device a
minute to get a fairly good fix (the first figure reported may be
quite a way out is you have been moving). Then mark
the point as a "waypoint" in OSMand.
the point as a "waypoint" in OSMand AND, without moving the phone, take a screenshot of the GPStest screen (see below) showing the lat./long., the time and the various accuracy metrics.
<h3>Camera locations</h3>
@@ -91,7 +91,7 @@ the point as a "waypoint" in OSMand.
<figure class=onright><a href='/handbook/computing/l/camera-ne-track.html'><img src='/handbook/computing/t/camera-ne-track.jpg' /></a><figcaption>Camera photo locations are not<br> on the track!</figcaption>
</figure>
<p>Your <em>camera</em> will use the same location settings as the rest of your phone, but sometimes with a bit of a delay. We have lots of examples of geo-located photos where the recorded location is alctually the location of the <em>previous</em> photo because someone has taken a quick photo but the phone hasn't had time after waking up to get a location, so it uses the previous one! And doesn't tell you!!
<p>Your <em>camera</em> will use the same location settings as the rest of your phone, but sometimes with a bit of a delay. We have lots of examples of geo-located photos where the recorded location is actually the location of the <em>previous</em> photo because someone has taken a quick photo but the phone hasn't had time after waking up to get a location, so it uses the previous one! And doesn't tell you!!
<p>So when taking a photo of an entrance, always take one photo; delete it, and take another. This will give your phone a chance to get synchronised properly.
@@ -111,7 +111,7 @@ track log, then record another waypoint at the same place just before you leave
so it's clear to someone examining the track log when you actually left.
</p>
<p>Averaging used to be very important, but today (2026) we have so many GNSS satellites in the sky that ionospheric effects are the significant error. These change slowly over 5 hours or so, so avergaing for a minute or and hour does nothing useful. You would need to average over several days. The solution for a fast fix is <a href="/handbook/computing/myphone.html#future">to use RTK</a>.
<p>Averaging used to be very important, but today (2026) we have so many GNSS satellites in the sky that ionospheric effects are the significant error. These change slowly over 5 hours or so, so averaging for a minute or an hour does nothing useful. You would need to average over several days. The solution for a fast fix is <a href="/handbook/computing/myphone.html#future">to use RTK</a>.
<p>While the GPS is averaging your location, you can do something useful
(like rigging the cave, doing a surface survey from the GPS point to the