Unlike the rest of us who are still dependant on the "altruism" of our manufacturers to "get around" to updating our background maps – and of course pay their exhorbitant fees – you can now "update" your maps to any image that you find more useful.
To top it all off, the process uses our favorite free geo-graphic program – Google Earth. And adding insult to our already burdensome Garmin-envy, our other favorite program, GPSvisualizer, is just waiting to make your new-found ability plush with multiple kinds of maps (subject of the next tutorial).
There are new beta software releases for these models which, finally, allow you to upload any map you wish into your handheld device and use as a map background! Explained in a new tutorial from Garmin the process is fairly simple. [Probably even more simple than the process of loading the beta update into your device.]
Basically all you need to do is: obtain the map you like in .JPG format, create a map overlay with it using Google Earth then "Save As" the .KMZ file into the /Garmin/CustomMaps/ directory on your units' memory card. Voila – the new functionality will display your personalized map geo-coded to the position you told it to.
The gentle reader will never, never know what a consummate ass he can become until he goes abroad. I speak now, of course, in the supposition that the gentle reader has not been abroad, and therefore is not already a consummate ass. If the case be otherwise, I beg his pardon and extend to him the cordial hand of fellowship and call him brother.”
The only caveat's are that Google Earth expects your image to be in .JPG format (so it may need to be converted) and Garmin expects your overlay file to be in .KMZ (zipped) format [so it contains the actual image and not just the code.] Give the file a short but descriptive name, and make sure you have the latest software unit in your GPS unit. That's it.
If I can find someone to borrow a Garmin uint from, I'll do a tutorial about it for you in the near future.
In any case I intend to do a tutorial (probably a screencast) about making screen overlays and how GPS Visualizer can help you do it — as soon as we get settled in winter Snowbird Headquarters. Right now we are trying to recover from 3" of snow dumped on our heads last night!