[Qgis-user] offline basemap in Qfield

[Simon Dietmann]

... we have good experience with study areas of up to 100+ km2 with a DOP in a resolution of 0,2m. The resulting geotif had about 9 GB and it was no problem to handle it as offline basemap on a normal android device.

Cheers, Simon

-----Ursprüngliche Nachricht-----
Von: QGIS-User <qgis-user-bounces at lists.osgeo.org> Im Auftrag von Huesmann, Michaela via QGIS-User
Gesendet: Montag, 14. Oktober 2024 17:08
An: qgis-user at lists.osgeo.org
Betreff: Re: [Qgis-user] offline basemap in Qfield

Hello Greg,

the data collection is to be carried out in an entire city area, which covers around 52km². I don't think anyone will just scroll through this area in the office before leaving the WiFi.

The mobile phone contract currently only allows a download volume of 1GB. I have no experience of how much data volume would be needed to download a WMS service or OSM maps for the entire city area on a mobile device while in the field.

Regards, Michaela



Mit freundlichen Grüßen
im Auftrag
Michaela Huesmann
Geodaten
Fachdienst Tiefbau

Tel.: +49 2552 925 219
Fax:
E-Mail: michaela.huesmann at Stadt-Steinfurt.de

, 48565, Steinfurt

-----Ursprüngliche Nachricht-----
Von: QGIS-User <qgis-user-bounces at lists.osgeo.org> Im Auftrag von Greg Troxel via QGIS-User
Gesendet: Montag, 14. Oktober 2024 15:00
An: Huesmann, Michaela via QGIS-User <qgis-user at lists.osgeo.org>
Betreff: Re: [Qgis-user] offline basemap in Qfield

"Huesmann, Michaela via QGIS-User" <qgis-user at lists.osgeo.org> writes:

> I would like to record data with Qfield using my Android mobile phone.
> In order not to use too much data volume, the base maps should be 
> downloaded via WiFi beforehand so that they can be used offline 
> outside. However, GPS must be used for orientation during the mobile 
> recording process. My questions about this:
> 1. Which map material for Germany can be used offline as  base map in my qfield project and how can I download it?
> 2. How do I ensure that the offline maps are used outside and that no download takes place while I navigate with GPS?

You didn't explain

  - How much data is too much?

  - What happens in terms of data if you just use an OSM mapnik basemap
    + in particualr, what if you open qfield on wifi and pan around to
      all the places you are going to be, to cause it to fetch data.
      Note that OSM requires that users of its tile service cache data
      for a reasonable period of time (7 days?), and thus QField should
      be caching.

  - What size area you are operating in?

I mean to ask "are you really sure you have a problem that needs solving?"

It is straigthforward to make a raster image of a small area and use that via "copy" in the now-oddly-named "cable" export.  (I use nextcloud to exchange bits, not an actual cable...)

Making something that can cover a larger area at varying resolution probably involves some sort of tiles-in-sqlite format.

In general, the only map data that I'm aware of with licensing that permits this sort of use is OpenStreetMap, and in the US, government data from the federal government and a number of states.  (I have no knowledge.de, but I'd expect similar -- OSM and maybe government.) _______________________________________________
QGIS-User mailing list
QGIS-User at lists.osgeo.org
List info: https://atpscan.global.hornetsecurity.com?d=BD0HOtPjGbI9raRERFdDA52OgRSP8NPiSq54-hnXIh4&f=fJICe8jjOAkkq28Wm3ffuMRxpWGqZENu_qV-xIhJu14&i=&k=M012&m=kzzxbu2okgXciaDyOL9QwZ-swCsbW29kiytUjLakjdFd4YA0O4qqZzfJkl9cdweREGqdlMxQbnhgxyxwVBUHeDCtazzVXuIgJwApfFwIRyyrXRD4dgAEXuM37aj_Wkb8&n=GA7wfEsQXV-GL8BUaVfR4PWfBFJkvvUKgTAf5gvOBvVp0pEOgikUWhJlulsoq3kJ&r=qb7emx5qX_IaUL2QuHT2F_q99hmR5RFHfZszmvc2bK5Qu_CybveEuNb7Rzv0b5kT&s=ee84d664369f3d65d38a4b415087a4e00bbb29a7b09f2a4b8e1ed42fe85bced8&u=https%3A%2F%2Flists.osgeo.org%2Fmailman%2Flistinfo%2Fqgis-user
Unsubscribe: https://atpscan.global.hornetsecurity.com?d=okISapn76EsVMAfbsBLmyoHgtHM54CfYwlMhoqWNTo8&f=qoQMiX-ezaz-hlfzHYEfWks2jYPGa5tSMlUDwT1MZ5Y&i=&k=fscl&m=_bCe1o9nQTMB03p1yhSJgFAuvrESdZ_ENplTP2jjygq9P2l7SlO80DPHt1XHFkEhzN3MoiADv3pYQoi752wZvtZvQE_zzbA5FUIYLdCOMgcLOApA6g-rUv-zenVZl4GS&n=jV9jT8agFFNKPGeNcaE8byuj4rjJLICKB29Rj3orNPNqDXisme9f6HSLIWH3mNsM&r=b6siIMsGRa_-_6qINkTIffxT6vh_DEwizuEdSmvCAEw65QKouh7bLB5z2zduUsNw&s=3690cf21cb9ba130c9aab99950f59c66482a20d594e983f4874a4929e7f94efc&u=https%3A%2F%2Flists.osgeo.org%2Fmailman%2Flistinfo%2Fqgis-user

_______________________________________________
QGIS-User mailing list
QGIS-User at lists.osgeo.org
List info: https://atpscan.global.hornetsecurity.com?d=KDm-mYHnfM4tRYDhqorOcJWyIVHijzUyQh0HaM4ueh4&f=aBOVRHM4n__jaqwcNJNM2pIv3CxQ22v7kkINz_qo9bc&i=&k=lgKW&m=7n3ePrSKdeOZVt9ewwAsTRPRslT5k6Xfi6CqOp6HsxOY7hEKaI3tuaRMCGzcUfQNDLny1CTBS3NxRUjC9z0HKY_F7oFp6WxTvo_ok3jgSCH8hoQZ2pne06z9n6epfPXU&n=CT7sJzdS2EV5b4vVi9ZwIxKdpJCedt5wMihuWnAfD2qnjYlHKIFOqhdXo4oPmQnV&r=rFYyCREDNSPvnvO-Hsq73oR-p3s18Rd8EF9dYgt9yYj6SjpdFIJ_nx8gE5q7I60j&s=3279896fbb8d62d7eb7b6231b502621ca50bdeb0081583ad3b8d686f9ed88fe4&u=https%3A%2F%2Flists.osgeo.org%2Fmailman%2Flistinfo%2Fqgis-user
Unsubscribe: https://atpscan.global.hornetsecurity.com?d=rTdBoGXEWeNBSv2U01_gIvovrizEbZjmN8EAUjG2WR0&f=DRD7mQKNh-OWxLY6SGSFq_AjJ1o7OjYnM48jcgxyjCk&i=&k=y8e7&m=_lBVmKWXyieT6WFtIBleiZvcxl-PUYuTVIOb0uuDWwCu7ZuRqE6j5th30MqqoMbMBNSuCnNWlI2wMybAUSDsOM091PJvF0I4kQvyamg9kkj4X96YlnsKyW_rAgIj1hom&n=i3UzL2gbY6kKoX0-dccGi2YpqZKfIk1jXlol_BFYeP7WEWwcdRerAoOBKBKYQxld&r=9hdk5UDVScIKe304bG8gpLZLEeadLb7PnbDv7N2zqIKWL6kr2auSyEQLy1w_k-1b&s=8f2e3e86b140373d8d2cf805b81fc2bf1cc3776fe5637221c837da3b59c13ab9&u=https%3A%2F%2Flists.osgeo.org%2Fmailman%2Flistinfo%2Fqgis-user