Avenza PDF Maps - GPS functionality

[fireball]

Hello all,

Quick question... I have the Avenza PDF maps app on my iphone. I am able to download the various PA state park and state forest maps into the app and open them but they do not provide GPS functionality.

For example, here is a link to the Bald Eagle State Forest map that I'd like to put into my phone and have GPS work with it:
http://www.dcnr.state.pa.us/forestry/stateforests/baldeagle/maps/index.htm

Am I doing something wrong? Does Avenza need to have a specific map in order to provide GPS overlay? Is there a different app I can use with the state park PDF maps that are available for download that will sync with GPS?

Thanks in advance for any help!

Ben

 

[robgendreau]

Yes, it needs PDFs that are georeferenced; they're referred to as geospatial PDFs and Adobe has certain specs for them. Essentially they include the metadata necessary to plot location. I'm guessing what you downloaded is just a map with no geo data. There are some tools online to use to add that data to PDFs, but I've found performance is often rather sloppy. The GaiaGPS help site I think has a link to one, and I seem to recall MIT had one. Otherwise you'd either have to get one of Avenza's cartography programs or something similar. And it won't matter what app you use if that state park map doesn't already have the geo data included within it (although some map formats can include it in a separate file). With MacGPSPro you can create take a PDF and georeference it and save it as a pict file. There might be some other applications out there to use depending on your platform (I imagine GRASS would do it too).

Rob