Recommendation for GPS Coordinate Standards (DMS or Decimal System)

[funrecdiver]

Bored and stuck in Thai Government Curfew Lockdown (TGCL) I did some research on dive sites and coordinates in Thailand.

Then I created a Google Docs spreadsheet template where anyone can read but we need to be logged into edit the spreadsheet. My idea was to have a collaborative (non-commercial, non-promotional) spreadsheet and when coords are "fully confirmed" we lock down (protect) the confirmed cells in the spreadsheets.

When I looked up some dive site coordinates (for example the HTMS Khram), I found a lot of errors on many web sites. Some web sites have the coordinates completely wrong, some use the wrong format, and the ones that seem to be "in the ball park" use different coordinate systems. For example, some sites use the two main "standards" which seem to be (based on conversion software):

1. DMS: Degrees Minutes Decimal-Seconds (with decimal seconds as required)
2. Decimal-Degrees

Some sites use odd systems that are not really considered "standard" (again, based on conversion software):

• Degrees Decimal-Minutes

There is one site (which I don't want to name and embarrass them) who incorrectly label "Degrees" as "Minutes" on an entire web page of Thai dive coordinates.

Also, few of the coordinates from various web sites were easy to "cut-and-paste" into Google Maps or Google Earth (and have the way point properly appear).

Hence, my thoughts were that the Thailand dive community could benefit from a reliable, collaborative spreadsheet where the coordinates are both accurate and easily cut-and-paste into Google Maps/Earth.

So, for this new "ambitious collaborative spreadsheet" effort I have hastily conceived during TGCL, what standard do you recommend for dive site coordinates?

 

[jamiemac]

Ha ha!

You'll have years of fun with this one.

I started collecting Thai wreck marks 20 years ago, when Loran was about and then when GPS arrived, should have been a God send but, as you say , there are so many different formats.

I wasted days at sea and loads of fuel being just off wrecks as I wasn't smart enough to convert the fishermens' co-ordinates into something I could enter into a GPS correctly

When I figured it all out, it was easy, motor up to the mark, spot it on the sounder, shot and dive.

You're going to see a least a dozen known formats, and some special ones fishermen use to confuse their competition.

Most widely used , and the most practical for navigation purposes is straight-forward degrees, minutes, seconds. GPS format WGS 84

I don't mess with decimals, the nearest second is approx 15yds, close enough for anybody. If you're working from WW2 records, this makes even more sense. The navigators on US subs here in the war are normally within 3nm of actual, not bad when you're estimating a position at night fleeing from a Jap escort

Knots and nautical miles simplify navigation and timings etc.

I have about 100 confirmed wrecks in the Gulf, about 30 being good dives, the rest being wooden fishing boats, barges, porta-cabins, planes etc

So that's my advice for what it's worth, but I'm not sharing the marks!

 

[lord khram]

When I figured it all out, it was easy, motor up to the mark, spot it on the sounder, shot and dive.

Most widely used , and the most practical for navigation purposes is straight-forward degrees, minutes, seconds. GPS format WGS 84

Quite right, simple ideas are quite often the best but all too often overlooked now we have all this modern technology available.

 

[funrecdiver]

Thanks for the feedback so far. Here are my thoughts.

First, if we go to my favorite on line tide table (based on xtide) and look at the current tidal conditions for Koh Si Chang the location information is expressed:

13.1500 N, 100.8167 E

If we cut-and-paste that into Google maps, we get a proper map of Koh Si Chang which also converts decimal-degrees to HMS for us:

+13° 9' 0.00", +100° 49' 0.12"

The problem is that, for many people at their keyboards, it is not so easy to find the right characters for ° (degrees). The keyboard chars for minutes ' and seconds, " is of course straight forward.

I think that is why a number of web sites have problems with HMS, because they cannot easily find the special character for degrees on their keyboard. (In fact, as I type now on my iMac, I have no idea where the degree symbol is, and therefore have to copy-and-paste it).

Since we are talking about data on the web, it seems that the notation:

13.1500 N, 100.8167 E

is the easiest because it can be both typed and cut-and-pasted into various programs (like xtides and Google maps) without issues.

OBTW, can anyone tell me where is the "Degrees Symbol" on the iMac keyboard? Windows XP keyboard? On a Nokia E63 keyboard? On the iPhone?

 

[Quero]

I'm sorry that I can't help you with marks at all, but there is one small thing I can contribute that might make your project a tiny bit less complicated:

Degree symbol on Macs = shift + option + 8

 

[funrecdiver]

I'm sorry that I can't help you with marks at all, but there is one small thing I can contribute that might make your project a tiny bit less complicated:

Degree symbol on Macs = shift + option + 8

Thank you! °°°°°°°°°°°°

OBTW, yesterday I was at Ocean Marina in Pattaya and reading some of their literature and noticed a number of yacht charter companies are discussing navigation in the decimal-degrees format mentioned earlier:

13.1500 N, 100.8167 E

I am thinking of taking a full course to get 400 hours of yacht training experience (and classroom time) that results in a bareboat yacht captain's license. Maybe I'll put this project on the back burner until I complete those courses.

 

[jamiemac]

Far too complicated for me, I work with tattooed southern Thai fishermen, singha beer and lat-longs scribbled on fag packets!

 

[funrecdiver]

Far too complicated for me, I work with tattooed southern Thai fishermen, singha beer and lat-longs scribbled on fag packets!

IKWYM, was talking to a diver the other day who preferred a plastic bag to a BCD, because he thought BCDs were too complicated; He made me feel a bit wimpish with modern electronics, dive computers, Internet databases, raised pinkies, designer sunglasses, dry bags, and chilled white wine.

I am one of those "health conscious metro liberals" who thinks that PADI should have a policy that smoking on dive boats from PADI DCs should be banned

 

[lord khram]

I am one of those "health conscious metro liberals" who thinks that PADI should have a policy that smoking on dive boats from PADI DCs should be banned

You would have to sack 90% of the instructors in Thailand, and at least 95% of the DM's.

 

[jamiemac]

You would have to sack 90% of the instructors in Thailand, and at least 95% of the DM's.

I'm with you there

I've slowly managed to restrict smokers on my live-aboard to the top deck, right at the stern, dirty, smelly lot. I wish I could ban them all together. I'm sure the day will come

And the fights they have about fags! They're big enough to smoke, but they never bring enough on board for a week at sea. Just as well it's me who organises the essentials - gas, food and beer.