Originally posted by Ishpuini Something is just dawning on me when reading through the discussion...
This unit interests me a lot since I was planning on doing some astrophotography (weather permitting) later this year when visiting Southern Argentina. And the location/heading data would be of great interest to me to locate the no doubt many landscapes I will be photographing along the roads.
Won't I be able to use it in the southern hemisphere at all? This would be a real disadvantage to me because I would expect to use this too on my next Safari(s), which is probably in Africa south of the equator too...
Tx in advance for clarifying this!!
Wim
GPS stands for Global Positioning System. Key word:
GLOBAL.
The NAVSTAR (original name for GPS) system was designed with a requirement for complete global coverage - a system that only worked "at home" would be useless for the Air Force and Navy.
Global Positioning System - Wikipedia, the free encyclopedia
However, augmentation systems that broadcast GPS correction data (local ionospheric conditions being the primary localized error source, satellite clock error is another but that's not localized) are local in scope.
WAAS only covers North America, and the scope where WAAS actually provides useful corrections (e.g. where iono information is valid) is even more limited than the signal coverage.
However, WAAS is only the difference between having around 10 meter potential error, and 5 meter or so potential error.
Edit: The European equivalent of WAAS is EGNOS. There's a Japanese equivalent too I believe. I don't think any augmentation systems are in use in the southern hemisphere, except for the classic local DGPS approach which few modern receivers support.