View Full Version : Chart/Datum confusion

28-06-2002, 03:47 PM
>:( :o After reading some recent press of late there appears to be some confusion with Australian map datum's and charts.

Australia's mapping datum is not AGD66 or AGD84 and hasn't been such for the past two and a half years. To continue to suggest that Australian charts ONLY use AGDS66/AGD84 is rather outdated and certainly miss-informed.

To suggest a wait for charts in Australia's new GDA datum is also rather a little behind the times as the first WGS84 (GDA94) charts were produced almost 10 years ago.

Currently approx 40% of all Australian charts are WGS84 (GDA94) with approximately 37% still in the "old" datum. In NSW something like 48% is WGS84(GDA94) with only 26% still in the "old" datum.

The important thing to take into account at this point in time is that there is a mixture of "old" charts and new GDA94/WGS84 charts available and this will continue until the agencies responsible release/update charts over a planned time frame. With this regard there is absolutely no difference between WGS84 and GDA94 as far as chart production/datum's are concerned.

Currently in the interim it all comes down to awareness but why some are suggesting WGS84/GDA94 charts don't exist is a bit baffling and rather confusing. Time for some to catch up with the times.

Cheers, Kerry.

11-07-2002, 01:27 PM
Good info Kerry, and most important for those who are plotting GPS marks from their charts to know what Datum the chart AND GPS is !

IN theory, you should only use AUS type navigation charts. The others are NOT recommended for navigation purposes, although they are very accurate. ( sunmap, hema's etc. )