diff --git a/handbook/computing/i/Screenshot_20260203-142503.jpg b/handbook/computing/i/Screenshot_20260203-142503.jpg new file mode 100644 index 000000000..01890369a Binary files /dev/null and b/handbook/computing/i/Screenshot_20260203-142503.jpg differ diff --git a/handbook/computing/l/Screenshot_20260203-142503.html b/handbook/computing/l/Screenshot_20260203-142503.html new file mode 100644 index 000000000..484c4f6cb --- /dev/null +++ b/handbook/computing/l/Screenshot_20260203-142503.html @@ -0,0 +1,24 @@ + + + + + +Settings + + + + + +

Settings

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settings
↺ rotate this image




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Photo © Philip Sargent, 2026

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+ + diff --git a/handbook/computing/myphone.html b/handbook/computing/myphone.html index 803f9e064..b01b7b3a4 100644 --- a/handbook/computing/myphone.html +++ b/handbook/computing/myphone.html @@ -112,5 +112,5 @@ Go on to Next survey guide page - 'B Your phone on expo - Do not select the "high accuracy" location setting on your phone (this page)
GPS essentials on the plateau - Safety information
Photo GPS - Is unreliable unless you follow procedure
- Locating Entrances - expo recommended methods
+ Locating Entrances - expo recommended methods
diff --git a/handbook/computing/phonecompass.html b/handbook/computing/phonecompass.html index 5e3f39361..6b77ab7bd 100644 --- a/handbook/computing/phonecompass.html +++ b/handbook/computing/phonecompass.html @@ -9,9 +9,9 @@

First of all, ensure that you have one. Compass & Altimeter is a good one, completely free (but turn off the altimeter setting as it does not do what you think it does).

Turn OFF "precise location" - all that does it connect to wi-fi and cell-phone masts so that it can send you targeted ads and guess your altitude based on the altitude of the wi-fi point. Entirely unuseful - and frankly misleading - on the plateau. +

Turn OFF altitude - useless and misleading on the plateau. -

- screenshot compass app settings +
 

Settings

Change the setting to MAGNETIC NORTH not True North. All our survey instruments use magnetic north, and this needs to be compatible with surveys. You may be using this compass app to determine the location of a cave entrance with respect to the nearest GPS point. You do NOT want "geographic" north.

Do NOT select "gradians" for the angle units. All our Austrian surveys use 360 degree angles, not 400 gradians, for a full circle. diff --git a/handbook/computing/t/Screenshot_20260203-142503.jpg b/handbook/computing/t/Screenshot_20260203-142503.jpg new file mode 100644 index 000000000..1550374a5 Binary files /dev/null and b/handbook/computing/t/Screenshot_20260203-142503.jpg differ diff --git a/handbook/essentials.html b/handbook/essentials.html index a7067c577..b1f906fcf 100644 --- a/handbook/essentials.html +++ b/handbook/essentials.html @@ -174,6 +174,6 @@ This should work the same way whether you have an iPhone or an Android phone. Your phone on expo - Do not select the "high accuracy" location setting on your phone
GPS essentials on the plateau - Safety information (this page)
Photo GPS - Is unreliable unless you follow procedure
- Locating Entrances - expo recommended methods
+ Locating Entrances - expo recommended methods

diff --git a/handbook/survey/gps.htm b/handbook/survey/gps.htm index e05173d60..3fff1f37b 100644 --- a/handbook/survey/gps.htm +++ b/handbook/survey/gps.htm @@ -117,6 +117,6 @@ on coordinate systems has been moved to a different page. If you are really Your phone on expo - Do not select the "high accuracy" location setting on your phone
GPS essentials on the plateau - Safety information
Photo GPS - Is unreliable unless you follow procedure
- Locating Entrances - expo recommended methods (this page)
+ Locating Entrances - expo recommended methods (this page)
diff --git a/years/2024/log_entries/2024-07-21c.json b/years/2024/log_entries/2024-07-21c.json index 2fd537fc6..97076926e 100644 --- a/years/2024/log_entries/2024-07-21c.json +++ b/years/2024/log_entries/2024-07-21c.json @@ -3,7 +3,7 @@ "title": "Photo - Photo GPS is unreliable", "place": "Photo", "other_people": "", - "text": "During this same trip walking to Geschandalm, later analysis of the GPS locations of various photos showed a lot of variability. \nThis is a particularly clear example where the location is obvious in the photo (it is definitely on the path) \nbut the GPS location stored by the phone camera is 60m away.\n

\nI had one phone (Xioami) continually tracking my location (using OSMand) which produced the GPX track, \nand another (Pixel) used for photographs. \nThe GPS data in the photos is clearly completely wrong for some of the photos - \npresumably because I hadn't left enough time for it to get a decent GPS fix before taking the photo. \nThis is particularly clear when there is a well-identified spot in the photo, \nsuch as this one right by the shady cliff (photo EXIF GPS locations are orange dots):
\n\n \n \n

\nThe lesson to take away from this is to always take TWO photos at any one position, and throw away the first one. \nThis will nearly always work for most people, and is sufficiently simple that even undergraduates can remember it.\nAdditionally, \n

  1. always continually record a GPS track on the phone you are using to take photos with - \nthough this is unfortunately not always reliable either, as the camera app tends to cache locations and doesn't always \nget a fresh one from the \"location\" module in the phone,\n
  2. Take a screenshot of the GPStest app showing current location and accuracy data. You can get it from F-Droid or Google Play Store.
      \n
    \n
\n

\n
\n
\nYour phone on expo - Do not select the \"high accuracy\" location setting on your phone
\nGPS essentials on the plateau - Safety information
\nPhoto GPS - Is unreliable unless you follow procedure (this page)
\n Locating Entrances - expo recommended methods
\n
", + "text": "During this same trip walking to Geschandalm, later analysis of the GPS locations of various photos showed a lot of variability. \nThis is a particularly clear example where the location is obvious in the photo (it is definitely on the path) \nbut the GPS location stored by the phone camera is 60m away.\n

\nI had one phone (Xioami) continually tracking my location (using OSMand) which produced the GPX track, \nand another (Pixel) used for photographs. \nThe GPS data in the photos is clearly completely wrong for some of the photos - \npresumably because I hadn't left enough time for it to get a decent GPS fix before taking the photo. \nThis is particularly clear when there is a well-identified spot in the photo, \nsuch as this one right by the shady cliff (photo EXIF GPS locations are orange dots):
\n\n \n \n

\nThe lesson to take away from this is to always take TWO photos at any one position, and throw away the first one. \nThis will nearly always work for most people, and is sufficiently simple that even undergraduates can remember it.\nAdditionally, \n

  1. always continually record a GPS track on the phone you are using to take photos with - \nthough this is unfortunately not always reliable either, as the camera app tends to cache locations and doesn't always \nget a fresh one from the \"location\" module in the phone,\n
  2. Take a screenshot of the GPStest app showing current location and accuracy data. You can get it from F-Droid or Google Play Store.
      \n
    \n
\n

\n
\n
\nYour phone on expo - Do not select the \"high accuracy\" location setting on your phone
\nGPS essentials on the plateau - Safety information
\nPhoto GPS - Is unreliable unless you follow procedure (this page)
\n Locating Entrances - expo recommended methods
\n
", "slug": "2024-07-21c", "time_underground": 0.0, "author": {