GPS positioning problem in Lambert 93

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1

Hrllo,
I am testing GPS location on QField windows with a simulator: Virtual GPS.
If my Qfield project is in EPSG 4326, no problem.
If it is in EPSG 2154 (Lambert 93), the GPS position and the shp layers (also in 2154) are very off.
Do I always have to work in EPSG 4326?
THANKS
Cordially
Gerard

Imported from GitHub discussion by @geguill on 2023-05-04T13:34:14Z

2

geguill , can you define very off?

Imported from GitHub comment by @nirvn on 2023-05-04T14:06:38Z

3

Sorry.
GPS position is in the wrong place relative to the layers.

Imported from GitHub comment by @geguill on 2023-05-04T14:22:58Z

4

Heh, that was clear already :wink: are we talking about 1 meter off or “the other side of the globe” off?

Imported from GitHub comment by @nirvn on 2023-05-04T14:27:27Z

5

About 5000 km to the south

Imported from GitHub comment by @geguill on 2023-05-04T14:29:41Z

6

geguill , ok, if you can attach a test project with a video that’d be of help

I’d try to check whether an epsg 4236 point layer reprojects properly in your epsg 2154 project within QGIS first. If there’s a problem there, it’s likely a project setting issue.

Imported from GitHub comment by @nirvn on 2023-05-04T14:35:10Z

7

essai_5.zip

Imported from GitHub comment by @geguill on 2023-05-04T15:07:39Z

8

Hi,
I have the exact same probleme.
QFIELD Lons.zip

Imported from GitHub comment by @Exebecce on 2023-07-19T12:56:48Z

9

Hi,
Do you have news about this problem ? It makes a while I didn’t use Qfield and I’ve got the same problem with the 2.8.7 version and Lambert 93 project. My vectorial data are in lambert 93, the basemap is also generated in Lambert 93, but when activating the GPS, this one is in WGS84 !
So I can’t see the data while activating the GPS off course.
In oldest version, I didn’t have such a problem.
test_stavertin_230905.zip

Imported from GitHub comment by @ludodo on 2023-09-05T12:56:26Z

10

To complete, I downgrade Qfield to version 2.7.6 and it works great, so something has been broken.

Imported from GitHub comment by @ludodo on 2023-09-05T13:35:59Z

11

ludodo , could you try to provide us with NMEA logs of your device from QField?

Documentation on how to do that is found here: Positioning (GNSS) - QField Ecosystem Documentation

Imported from GitHub comment by @nirvn on 2023-09-05T14:31:48Z

12

For me, the problem has been solved by deleting Qfield from the smartphone and installing it back.

Le 5 septembre 2023 16:31:59 GMT+02:00, Mathieu Pellerin @.***> a écrit :

ludodo , could you try to provide us with NMEA logs of your device from QField?

Documentation on how to do that is found here: Positioning (GNSS) - QField Ecosystem Documentation

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Fabien Leprince

Imported from GitHub comment by @Exebecce on 2023-09-05T18:14:54Z

13

Not for us, and on twos different devices

Imported from GitHub comment by @ludodo on 2023-09-08T12:17:00Z

14

I do not use an external receiver. so I don’t have the option proposed in the positionning window.
On one off the device, installing a version 2.7.6 works, and then, update to 2.8.7 doesn’t brake the resolution.
But on anther device (crosscall), it doesn(t work with any version.

Imported from GitHub comment by @ludodo on 2023-09-08T12:29:44Z