Question about transparent topo maps

[gallet]

I understand that for more than one Garmin Map to be visible they need to be loaded to the card together. But I was wondering if an SD card is already loaded with a non garmin transparent topo map like the OZtopo Tracks4Australia maps, and then the garmin folder with the .img map file is copied to the sd card, will both be visible on the unit at the same time?

Edited December 26, 2007 by gallet

[QuigleyJones]

Its my understanding that all maps are not viewable at the same time.

[gallet]

Its my understanding that all maps are not viewable at the same time.

 

So what is meant by a transparent map?

[rws]

I understand that for more than one Garmin Map to be visible they need to be loaded to the card together. But I was wondering if an SD card is already loaded with a non garmin transparent topo map like the OZtopo Tracks4Australia maps, and then the garmin folder with the .img map file is copied to the sd card, will both be visible on the unit at the same time?

 

You have to upload both maps together in one shot. The transparent map will overlay the Garmin map allowing it to show through.

[tlhutch]

ALL maps loaded onto a Garmin unit MUST be loaded as a mapset. That means that they are loaded at the same time as one large .img file. Otherwise, separate uploads OVERWRITE the previous one.

 

Several different types of maps can be included in a mapset. CN, TOPO 2008, or transparent DIY's must all be loaded together. Now, which map is shown on the GPSr screen is dependant upon which map is selected via the Menus. For example, if both TOPO and CN are selected to be shown then ONLY CN will show on the GPSr screen because it takes precidence in the Garmin firmware hierarchy.

 

The exception to this firmware rule is that if the map is transparent it will show in addition to the other map loaded. A transparent map will be displayed on top of (in addition to) either CN or TOPO. The features of BOTH MAPS are visibile at the same time. It is similar to placeing a piece of plexiglass or a transparent sheet of polycarbon over a paper map. Anything written on the polycarbonate will show along with the paper map features.

 

Currently, the only transparent maps available are either DIY or small specialized commercial units selling on a small scale. None of the big map makers market them.

 

Is it clear (transparent) now?

 

ETA: If the OZtopo Tracks4Australia maps are actually in a .img file they would need to be loaded into MapSource and loaded to the unit (mSD Card) together with the other segments. If they are in a .gpx file, they are not maps and would be OK on the card, as is. In that case they will display as tracks, not maps.

Edited December 26, 2007 by tlhutch