I want to make a map (of Germany) with certain positions marked. This is just a MWE, in fact there are much more positions. What I did:
positions = {{47.5`, 11.08`}, {47.57`, 8.03`}, {47.6`,
8.13`}, {47.65`, 7.6`}, {47.65`, 7.78`}, {47.66`, 9.48`}, {47.7`,
10.32`}, {47.73`, 12.1`}, {47.77`, 9.72`}, {47.77`, 11.62`}}
and
marker = Graphics[{Blue, PointSize[0.4], Point[{0, 0}]}];
then (this - Entity - is keyed in manually because of the complicated structure of the Entity in this command when done via copy and paste)
map = GeoGraphics[{GeoStyling["StreetMap"],
Polygon[Entity["Country","Germany"]],
GeoZoomLevel -> 9,
GeoMarker[positions, marker]
},
GeoBackground -> None, ImageSize -> 2000]
If I do so the map looks fine:
If I export the image:
Export["germany-04.JPG", map, "JPG"];
and re-import the image it is much more coarse. I tried with something like
Export["germany-04.JPG", map, "JPG", ImageResolution-> 300];
and explicit ImageSize, but I never get close to the the original resolution (same with export formats like SVG, EPS, PNG. If I copy the map (as graphics) and try to import in Photoshop.... Mathematica crashes (??).
My system: MacOS 10.13.5, Mathematica 11.3.0, my goal is to get an exported image good for print.
"JPG"
) image files has lossy compression, and Mathematica uses a"CompressionLevel"
of0.25
by default. $\endgroup$