October 22, 2008 13:32
OzSailor Wrote:Now, if I go to the state of Queensland (where they don't have DST, or Western Australia, where it starts this Sunday (eastern states of Australia began beginning of October -- don't ask why, long story: times here http://www.australia.gov.au/Time), I presume my iPhone will recognise the local time, and will AyeTides also adjust accordingly?
Another thing I've noticed (and sorry if this seems over-picky) is that the times and heights in AyeTides can differ by up to 15 minutes, and by up to 150 mm from the "official" tide times/heights.
Hi OzSailor, nice to hear from you!
Yes the iPhone should adjust automatically for Summer Time. The underlying code is all OS X and it handles all the time zone and summer time changes without me having to do anything. Quite amazing, really!
As for the tides being off, the harmonics for Australia are somewhat old. The Australian tide people (can't think right off the bat who they are) haven't released any new ones and they admitted years ago that the ones I have aren't accurate. But they refuse to release any ones that are better. There is a book that I was sent having some harmonics in it, but only 8 (in some cases fewer) listed and that's generally not enough to make accurate predictions. They'll be "close" but not the same as the official tide predictions. It's the same problem I have with the British harmonics; they only give 4 and admit that they use up to 140, so there's no way I can be as accurate as they are.
Well, maybe 'accurate' is the wrong word. I can't match what they have, but unless someone on the ground can watch the tide and can say when and how high it was, then who knows which set of predictions is right?