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Using QGIS on Windows 7, I have figured out how to burn a vector file onto a QGIS georeferenced tiff. But the result produces a line only one pixel wide. I am trying to produce a map that can be used both as printed and on a mobile device to guide hikers and the narrow line isn't sufficiently visible.

Is there a way to make the line wider or otherwise more visible?

I am a non-programer and completely new to QGIS.

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  • Are you using the print composer? docs.qgis.org/2.0/en/docs/user_manual/print_composer/…
    – Mapperz
    Jul 29, 2016 at 20:07
  • No. I use Raster>Conversion>Rasterize. One benefit is that it keeps the georeferencing and resolution of the tiff intact. I've found print composer difficult to work with in maintaining the level of detail in the tiff map.
    – Pooneil
    Jul 29, 2016 at 20:55
  • Your comment prompted me work some more with Map Composer and I found a few ways to make it work much better. Thanks. I would still like not to re-reference the Tiff files, just to save some time. So further information from anyone would be a help.
    – Pooneil
    Jul 29, 2016 at 22:34
  • As a final follow up to this question. I've learned to use print composer to produce the kinds of maps I need. Re-Referencing the new tif map is no long much of a problem because I've found it easy to use the referencer and use the map canvas as the source for the new points. It only takes a few minutes and produces very good geotiffs suitable for making KMZ files. Thanks to underdark for the help and pointers.
    – Pooneil
    Aug 31, 2016 at 22:58

3 Answers 3

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Buffer the lines. You can make them as thick as you want that way. Then rasterize the resulting polygon layer.

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  • Thank you. I'll look at that. How do i buffer the lines?
    – Pooneil
    Jul 30, 2016 at 22:45
  • @Pooneil Please read the manual and/or watch some tutorials e.g. youtube.com/watch?v=b3c_XRY7oQs
    – underdark
    Jul 31, 2016 at 8:45
  • Thanks for the link. I'll watch it. I am unfamiliar with the terms and processes of GIS and trying to learn so you pointers are a big help.
    – Pooneil
    Jul 31, 2016 at 23:49
  • Thanks again, I know know what buffering is in a GIS context. It doesn't seem to be applicable to rasterizing a shape file directly onto a TIFF file in a way that is more than a pixel wide line. Perhaps that is just not possible in QGIS, but if I am missing something here please let me know. Whether it is or not, your pointers have helped me get from not knowing how to do this to seeking a way to get what I need more efficiently. So thanks again.
    – Pooneil
    Aug 1, 2016 at 12:02
  • OK. Now I see it. The shapefile created as the line buffer can be rasterized onto the tiff. Yes this is just what I've been wanting to do. Thanks.
    – Pooneil
    Aug 1, 2016 at 12:40
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You can use "Save as Image" from the project menu. This produces a georeferenced image from the QGIS view. You can change the vector styling to make the line thicker. The limitation is that you have no control over the output image resolution.

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I'm not a qgis expert but this sounds like a job for a KML. A KML would be easy to overlay in an application and in print. KML was developed for Google Earth/Google Maps.

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  • Yes it does. However the vector track within the KMZ will not appear on a Garmin GPS or in the phone app I am using. I am hoping to make this work as easily as possible for people with various devices for the mobile map. Printing from Google Earth at high resolution is a problem.
    – Pooneil
    Jul 29, 2016 at 21:01

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