GIS/Mapping Apps

[Scooter]

This doesn't seem to have been mentioned here yet, but the Backroad Mapbooks digital versions are quite useful. Here's more info:

https://jonathan-scooter-clark.blogspot ... nters.html

[Scooter]

Here's a suggestion I just found online with respect to using Google images to create GeoTIFF's. I haven't tried it yet, but it might be allowable for personal use:

Definitely not endorsed, but you can do this approach:

1. Add an XYZ tile source for the Google Maps layer:

http://mt0.google.com /vt/lyrs=y&hl=en&x={x}&y={y}&z={z}&s=Ga (remove the space after google.com ... I had to write it this way so it doesn't convert to a shortened hyperlink)

2. Add the layer to your map, zoom to desired region

3. Right click the layer, Save As
Set format to GeoTIFF
Untick "Create VRT"
Enter a filename
Under Extent, click "Map view extent"
Under Resolution, make sure you use the horizontal/vertical resolution option and NOT the columns/rows option. Enter a reasonable resolution (units are meters per pixel), and make sure both the horizontal and vertical resolution are equal. If the generated rows/columns values are extreme, drop your resolution.

4. Click OK and wait while the tiles are downloaded and saved to the GeoTIFF destination.

Ideally, someone needs to write an android app that converts GE or Bing base imagery into a high quality georeferenced image, legally. If that existed, I'd probably pay $100 for such an app.

There's an app called "Custom Maps" by Marko Teittinen which may do exactly that, although you have to jump through a few hoops. What I'd do would be to export a tiled image from the base layer, using the highest possible resolution, and then create the tie-points to that exported graphic. I'll have to play with it to see how well I can get it to work.

[Nate]

ESRI Collector is the most powerful I've come across but requires active licenses.

I used OziExplorer day-to-day right now but am looking at Gaia Maps pretty close.

I cut all my raster maps in GlobalMapper, which is a boss-ass GIS program.

[Sunwatersoil]

Avenza Maps (formerly PDF Maps) as of Sept. 2018 no longer supports Android 5.1 OS or older. A system requirement of Android 6+ is now in effect. This is a bit of a headache for me as I use a Sonimtech XP7700 mfd. 2015 specifically for payplotting and my device no longer supports Android OS updates.

You can find older copies of PDF Maps before the 3 map limit was introduced on APKPure, an android app copy site. I proceeded to download version 1.7.3 (24/5/2016) before the 3 map limit went into effect. In order to upload the .apk file onto my phone I had to download an APK installer, the app was called APK Installer coincidentally. I transferred the .apk file into a folder in my phone, and using the APK Installer app I was able to load the old but free/unlimited maps version with no problem. Just remember to uninstall the previous Avenza Maps app beforehand or it won't work.

You can also use this method should you wish to avoid paying the $29.99 usd annual fee. Cheers.

[Scooter]

That version (1.7.3) from APKPure is the one that I've been using for the past two years. However, there's one very important thing that you have to do:

Go into the Google Play store and find Avenza, and disable auto-update. Otherwise, the new version of the app will be downloaded and installed fairly soon and you'll have to go through the whole process again. The easiest way to disable auto-updates is in the settings on the specific Avenza Maps download page on Google Play, not within the app settings on the phone.

[Scooter]

Add this one to your list of best websites for tree planters:
https://apps.sentinel-hub.com/sentinel-playground/

Great for assessing snow load levels. The imagery is updated very frequently.

[Scooter]

This could be a major new development. Version 3.10.0 of QGIS was released on November 2nd, and according to the changelog, there is now native support for embedding georeference information in PDF's and TIFF's. Here's a link to the changelog:
https://qgis.org/en/site/forusers/visua ... -image-pdf

I'm going to play with this tomorrow, since I have to finish designing a trail system on one of my own woodlots anyway, and see how well this works.

[Scooter]

Yeah, so the new version of QGIS does indeed let you create a georeferenced map very quickly and relatively easily from google satellite imagery. I'll put some notes here in December when I have more time, about how to do it. I did tests this weekend with three of my woodlots, and they all worked fine. It would also be pretty easy to create your own large map, say if you wanted to go into a provincial park with no cell coverage and see where you are at any given time.

On a separate note, I'm pretty sure that Avenza Maps doesn't allow users to edit GPS tracks. That's annoying. I suppose it could probably be done by exporting the series of points in the track as a CSV spreadsheet, and just deleting a bunch of the points. But that's too technical. What would be better would be able to highlight a rectangle and be able to press a "delete points" button and have all the track points within that rectangle erased from the track.

Case in point is the graphic below. I was walking the boundary of a woodlot this afternoon, which is the orange track coming in from the bottom of this photo. It was fine for most of the way, even though I had my phone inside my hi-vis vest pocket, because it was a perforated hi-vis and the GPS signal was getting through to the phone with no problems for most of the way. I was ribboning the boundary, which is why I didn't just carry the phone out in the open. Anyway, near the point at the top (which I circled in red with photoshop) the phone DID lose the GPS signal for probably 30-60 seconds. When it reconnected, it was inaccurate, jumping for just a second up to a point in the woods north of where I was actually standing. It then quickly jumped back to my true position. But that brief incorrect position point made a false jog up into the bush which shouldn't be on the map. It would be nice to be able to highlight a very small polygon that includes that point and to have the point deleted from the track, which would effectively straighten out the line. Of course, it would create a straight-line assumption between the remaining points on either side, but in this case that would certainly be better than what's there now.

[Scooter]

A tip for Avenza users on Android. Make sure that your "Power Saving Mode" is always turned off. Otherwise, if you're trying to do a GPS track in Avenza and you turn the screen off, the app also stops capturing GPS location until the screen is turned back on. This can give you a very erratic track.