For me the inReach has become an essential part of my kit regardless. I too dig map and compass and while I know that while in the Southern Hemisphere looking at the sun, West will be on my left. But you got me thinking about something I don't know, and that is about magnetic declination/variation in the Southern Hemisphere. I wonder, is it treated like it is in the Northern Hemisphere?If someone could clear that up for me, much appreciated.
Not sure how it’s done in the Northern hemisphere and I’m no expert but we have the magnetic delineation marked on the legend of the map, it changes annually but only marginally, hopefully you would navigate to a sizeable landmark without going past.
My understanding is that our compass is oriented for the Southern Hemisphere so the needle points north. I guess others point north but it’s a polar opposite magnetic needle.
So if magnetic delineation is 2 degrees and we are putting our magnetic north to orient the map we add 2 degrees as we are adding the bearing to the map..
taking a bearing from the map then take away the delineation to get true north. .
I hope that helps, I use an Inreach for work. While the coordinates have proven correct the map image on the screen taken from base map is showing about 10 km off sitting south of a known point and shaded boundary. I asked the GIS mapping staff gurus and they confirmed sometime base map is a little off. For the purpose of calling in a coordinate it is spot on. Looking at it my house/waypoint looked like it was on a known intersection of remote rural roads that I know well.
If you flew to coordinates you’d be right on if I pointed to the point on the map of the road intersection or sent it as a screen shot you’d be off and when you got there the coordinates would not be those of the house.
But if you had a waypoint of the hunting lodge, the road a dam or relevant points and maintain battery you can reverse your route or set a bearing if you are stuck.
I’m not sure if GPS can be used in either hemisphere but the term Global Positioning System would indicate it works globally. As for a compass I think at worst it will be 180degrees out showing south as north or something, as long as wea are aware. If you hunt internationally grab appropriate compass in country, even a cheap compass works. One bearing to a safe waypoint is all you need, ohh and maybe protection against dangerous game in some places.