Better coordinates

[+rcccraft]

Hello community, I have recently noticed that the Geocaching app for IPhone only takes you about 10-40 ft within the actual coordinates, if you can fix this bug, that would be helpful

[+kunarion]

How did you determine the actual coordinates?

[+IceColdUK]

I’d be very surprised if it was anything to do with the app.  Have you tried comparing your coordinates from the Geocaching app with those on any others, such as the inbuilt Compass?

[+IceColdUK]

These screenshots show my Current Location according to the Geocaching app (on the Add Waypoint screen) and the current coordinates on the iPhone Compass.  Unfortunately, the formats are different (DD MM.MMM vs DD MM SS), but if you do the maths you’ll see they’re the same.

[+kunarion]

6 hours ago, IceColdUK said:

These screenshots show my Current Location according to the Geocaching app (on the Add Waypoint screen) and the current coordinates on the iPhone Compass.  Unfortunately, the formats are different (DD MM.MMM vs DD MM SS), but if you do the maths you’ll see they’re the same.

 

The iPhone's coordinate format of DD MM SS in its built-in compass may not be as good as DD MM.MMM seen in other GPS Apps.  If the OP is comparing the two, there's the problem.  Even comparing two Geocaching Apps there will be differences, since the calculations are always happening.

 

If the OP is instead comparing the posted cache coordinates to the place that his phone identifies as "0", now we're in the realm of GPS precision. The hider's coordinates were an average of millions GPS calculations, and so are the finder's.  The cache is hidden and found in different atmospheric conditions, with different tree cover. Most, probably all Cache Owners, will not perform "GPS averaging" over all seasons, times of day and weather conditions. They take a couple of waypoint snapshots at most, which is often just fine for Geocaching. GPS positioning the finder at 10 feet from a cache is an outstanding result, and 40 feet is not unheard of.  Read the cache page, look at the satellite map, and then put the GPS away, start looking.

 

Edited August 24, 2018 by kunarion

[+IceColdUK]

16 minutes ago, kunarion said:

The iPhone's coordinate format of DD MM SS in its built-in compass may not be as good as DD MM.MMM seen in other GPS Apps.  If the OP is comparing the two, there's the problem.  Even comparing two Geocaching Apps there will be differences, since the calculations are always happening.

 

I was just trying to illustrate that GPSr accuracy is not a feature of the app, but a function of the phone.  If the app is way out, the Compass will be too.

 

But as you suggest, maybe the OP’s expectations are too high.

 

11 hours ago, rcccraft said:

takes you about 10-40 ft

 

10 feet is pretty good. :-)

[+HHL]

11 hours ago, rcccraft said:

Hello community, I have recently noticed that the Geocaching app for IPhone only takes you about 10-40 ft within the actual coordinates, if you can fix this bug, that would be helpful

Yes, that's because the compass supresses the decimal second part. ;-(

One geographical second spans appr. 30 m latitude and 20 m longitude. Supressing those decimal part results in non precise coords.

 

Hans

Edited August 24, 2018 by HHL

[+IceColdUK]

13 minutes ago, HHL said:

Yes, that's because the compass supresses the decimal second part. ;-(

One geographical second spans appr. 30 m latitude and 20 m longitude. Supressing those decimal part results in non precise coords.

 

Hans

 

Looks like I’ve really confused things by showing my screenshot of the Compass.  Sorry.

 

OP’s concern was with the accuracy of the Geocaching App on the iPhone...

[+kunarion]

15 minutes ago, IceColdUK said:

 

Looks like I’ve really confused things by showing my screenshot of the Compass.  Sorry.

 

OP’s concern was with the accuracy of the Geocaching App on the iPhone...

 

I think you may be right on.  If the OP compares Apps within the iPhone itself, the results will vary.  But the built-in App is wrong, or not as precise as the Geocaching App.  The Geocaching App is as OK as it's gonna get, as it applies to precision, the ability to place you at a point consistently.  A point that will be different for each user in varied conditions with various devices.  And different from moment to moment within the same App.  This ain't rocket surgery.

 

Edited August 24, 2018 by kunarion

[+cerberus1]

12 hours ago, rcccraft said:

Hello community, I have recently noticed that the Geocaching app for IPhone only takes you about 10-40 ft within the actual coordinates, if you can fix this bug, that would be helpful

 

Not sure if you're kidding or not...

Civilian GPS is only "accurate" on it's best day at 10'.  That means the CO as well as you have to have a "best day" to make it 10'.

 - Best days don't happen often, and your best bet is to put that phone away when you realize you're heading to GZ and start looking.