Degrees, Minutes & Seconds Conversion

[skipmac]

Originally Posted by sailorchic34

Well really, feet, fathoms and D,M,S work just as well, and have been used for a really long time. Its a US standard. .

I can deal with feet and fathoms or metric. What is annoying is when I'm using software or online chart viewers and can't tell if the data is in ft or fathoms since I can't just look up at the corner of the chart for the reference. And it can change depending on the zoom level if the viewer switches charts.

Originally Posted by sailorchic34

Much like the British still use the pound and not the euro. Not to mention that we're a pig headed lot.

At least they gave up shillings and pence crowns and farthings and guineas. I can deal with decimal pounds but all that other stuff would give me a headache.

[Tx J]

Originally Posted by F51

Thanks, TX J. Whew! It is going to take a while to digest that Martindale stuff. I found online calculations that do almost exactly what I need. Now if I can get something I can download to use when I am out of range of the internet it will be great!

Yeah, Martindale can get deep and muddy real quick, but has lots of useful stuff.
A Bing search turns up lots of L/L conversions:
convert latitude and longitude - Bing

This one in particular does all three common L/L conversions that you're looking for:
GPS Latitude and Longitude Converter

If you scroll down, past the converter and map, that page has some useful Nav and GPS type information.

Hint:
If you save that webpage to a folder (like your "Nav" folder or whatever) as a "web archive" (in IE- Menu- File_Save As- choose Type_web archive single file ), you will have saved an almost fully functional L/L converter webpage to use offline as you would a standalone app (the elements that go to other (ad/active) links won't present).

When you aren't online you can simply find the .mht file you saved (titled in this case: GPS Latitude and Longitude Converter ), doubleclick on it ('open it'), and it will open in a browser window at anytime, without needing to be connected/online.
Each browser, if you're using something other than Internet Explorer, will handle this "Save webpage as archive" process slightly differently, but still work.

Plug in your L/L and convert it, while you're offline.


The saved webpage (archive) has fully self-contained JavaScript code that does all the L/L calculations right there within the browser renderer/interpreter (offline, and safer too). If you're familiar with HTML, just examine the page source to verify.
JavaScript - Wikipedia, the free encyclopedia

A handy trick that can be used with many webpages, for using them offline.
Create a shortcut on your Desktop and/or Programs List and have the new 'App' ready to use anytime.

[vtlli]

Originally Posted by F51

I am constantly having to convert lats & longs from degrees, minutes, seconds to degrees, minutes & decimal minutes or just decimal degrees. I am looking for an excel spreadsheet that will handle these conversions both ways. Any ideas? Thanks.

Few year ago I bought over Amazon cheap engineering calculator (casio fx- Gt plus). It can do this conversation. Also it can do simple arithmetic with dd:mm:ss. Lets say: 53’06”12 - 52’18”56 = 0’47”16 or sqrt if you need

[Jammer Six]

Originally Posted by sailorchic34

Cough, Those pesky USA folks keep using charts in feet and fathoms and yes the edge marking are in DD,MM,SS (Just checked the latest NOAA charts).

Actually, it's a test to keep our navigators awake and to let skippers in the know catch inexperienced navigators.

Not all the edge markings on NOAA charts are DD-MM-SS. Some are DD-MM.MMM, and some DD-MM.MMM charts have one tenth divided in six. (Which is both.)

I find the "both" option the most annoying to use.

[PauHana]

Excel is great if you have a lot of numbers to work with.
However, Excel only calculates angles in radians.
You do the conversion you want if you enter Deg:Min:Sec as a time value, which is also base 60, then display it in a different cell as decimal hours.
check this page for some good ideas:
Latitude And Longitude

I love my mechanical pencil.

[FamilyVan]

First of all. If you want to Navigate, forget about base 100. I am Canadian, so I was brought up with metric/base 100 system. However, I am also a Navigator and recognise that base 60 and 360 are just inherently better than base 100.
For example: 60 is equally divisible by 1,2,3,4,5,6,10,12,15,20,30 and 60. Whereas 100 is equally divisible by 1,2,4,5,10,20,25 and 50 and 100. Meaning 60 is divisible by 12 whole numbers where 100 is only divisible by 9.
IMHO 60 is a better number than 100.

[jackdale]

Originally Posted by Time2Go

What type of pencils are best used on Charts?
Thin? Thick? Hard? Soft?

I use a .9 mm mechanical pencil with soft lead.

BTW - use a white eraser, the pink ones really destroy a chart.

[jackdale]

Originally Posted by JohnT

Why on earth have "those pesky USA folks" not converted like the rest of the world?

Then there is chart datum. American and Canadian chart datum is different. It gets exciting when you use a chart that crosses the border and chart datum changes as well. The difference can be as much as 1.8 meters.

Getting folks to change can be tough. While the vast majority of Canadian charts have metric depths the tables to make corrections between reference and secondary ports for tides are in feet only. When the hydrographic service tried to change to metric conversions there was a huge uproar.

[Jammer Six]

.05 mechanical pencils, 2B lead.

I would use .03 lead, but they break too often.

Learn the ruler trick. That will be the end of conversions, although dividers and one line to the nearest grid are still what I use when accuracy counts.

[FamilyVan]

As stated above 2B. The reason being anything hb or harder requires too much pressure to make a mark and will leave indents all over your chart. And it's harder to erase.

Sent from my SGH-I547C using Cruisers Sailing Forum mobile app

[valhalla360]

It's really not that hard to set up a simple spreadsheet:

degree/min/sec to decimal degree:

Set up 3 cells:
- Degree
- Min
- Sec

Then write a formula in another cells that adds up: degrees + min/60 + sec/60/60.
The result will be decimal degrees.

The other way is slightly more complicated but not too difficult.

Set up a cell with the decimal degree (X in the formulas below). then put formulas in 3 cells
- Degrees: @rounddown(X, 0)
- Min: @rounddown((X-Degrees)*60,0)
- Sec: (X-degrees-min/60)*60*60

Once set up, you can enterr either one and it will spit out the answer.

I've run across this before and can't believe excel doesn't have a function to do this directly, though you could set up a special function but I've never bothered.

[HappySeagull]

Originally Posted by F51

I am constantly having to convert lats & longs from degrees, minutes, seconds to degrees, minutes & decimal minutes or just decimal degrees. I am looking for an excel spreadsheet that will handle these conversions both ways. Any ideas? Thanks.

Try a stand-alone portable application GPS Sway
available here
GPS Sway - Coordinate Coverter - GPSFileDepot