Degrees, Minutes & Seconds Conversion

[achil]

Originally Posted by El Pinguino

Whats rong with doing the simple stuff in your head?

I do lots of stuff in my head... which is a bit of a worry......and a little bit scary

Absolutely nothing wrong with doing things in your head. I am a firm believer in doing what is easiest to come up with a correct answer in anything. However, there are people from all over the world on this list and from all kinds of backgrounds. Your original answer was to divide by 6, nothing was said about moving the decimal one point to the left. I don't know if that was just an oversight on your part or not. I just pointed it out so that anyone using your figures would know they needed to move the decimal point.

[achil]

Originally Posted by CLady

This seems to be an engineer, or wanna be engineer, setting up an EXCEL spreadsheet to convert minutes and seconds like this. Dividing by 6 or multiplying by 6 is good. Hmmm, does he perhaps have a mechanical pencil tucked neatly in a vinyl pocket protector inserted in his short-sleeved dress shirt breast pocket?

If you are referring to my post, I am neither an engineer or a wannabe engineer. I just don't believe in been off on measurements by a factor of 10.

[Stu Jackson]

And remember, if you're subtracting rather than just converting, it's not just simple arithmetic, you have to "carry" the 60 degrees, minutes, seconds, etc.

[Time2Go]

This brings me to an interesting question
and I'm not trying to be flip
So here goes
What type of pencils are best used on Charts?
Thin? Thick? Hard? Soft?
What's the proper way to hold the pencil to the ruler?
I'm self taught in these matters and while we are discussing
Thousands of a minute, on my last trip it occurred to me that I
Had to make allowances for the soft pencils on board.
They wouldn't hold a good point and made a thick line.
What's the best to use?

[El Pinguino]

Originally Posted by achil

Absolutely nothing wrong with doing things in your head. I am a firm believer in doing what is easiest to come up with a correct answer in anything. However, there are people from all over the world on this list and from all kinds of backgrounds. Your original answer was to divide by 6, nothing was said about moving the decimal one point to the left. I don't know if that was just an oversight on your part or not. I just pointed it out so that anyone using your figures would know they needed to move the decimal point.

Ok ..lets try this....
Ignore what I first wrote "just divide by 6 in your head.... 36" = .6' , 40" =.66' "

and try this ' divide the seconds by 6 in your head... write the number thus found to the right of the whole minutes.... insert a decimal point between the two numbers.... ie 10 minutes 36 seconds... divide the 42 by six... this will give you 7... write down the 10 and then right down the 7.... now insert a decimal point between the 10 and the 7 so that it looks like this 10.7

I think my original description was pretty obvious to most people as you can see that a decimal point has been inserted.... mind you we could divide by 60 .... 60 into 44 doesn't go, 60 into 440 goes 7 times and carry 20, 60 into 20 doesn't go.... stuff this I think I'll make an Excel spreadsheet......

[El Pinguino]

2B pencils always....

When subtracting convert the last degree in the number you are subtracting from into minutes.... ie want to subtract 27*41' from 159*00' ?
158* 60'
- 27* 41'
------------
131* 19'

Makes life a lot simpler when working with LHA's, GHA's, and Westerly longitudes.

[JohnT]

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.

Why would you need to make these calculations? In the international marine industry all positions are in DD:MM.ddd and all paper charts are published in the metric system. Just set your GPS to the same standard. Or am I missing something?

[CLady]

You can get fine soft lead mechanical pencils--BIC makes them--they're safety yellow in color and are very inexpensive. They last a long time. They also have a soft eraser tip at the top.

[sailorchic34]

Originally Posted by JohnT

Why would you need to make these calculations? In the international marine industry all positions are in DD:MM.ddd and all paper charts are published in the metric system. Just set your GPS to the same standard. Or am I missing something?

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).

[CLady]

Yes--taking notice of which, is easily forgotten. Some of us do the metric and some do what's on their chart or programmed in their GPS//chartplotter. Checking the charts is good. NOAA Ocean Prediction Center is fickle as well. Just note the weather charts--sometimes the wave heights are in meters, and sometimes, they are in feet.

[JohnT]

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).

That's funny, I bought an approaches chart to Port Everglades two years ago and it is a metric chart - I must haul it out and check who published it as it may be a BA chart! Why on earth have "those pesky USA folks" not converted like the rest of the world? Even us backward African dudes converted all our nautical charts a few decades ago to the internationally accepted norms and conventions.

[F51]

It doesn't matter what the standards are if the data you are dealing with does not conform to the standard. I thought mine was a simple question that might elicit a simple answer, but apparently I ruffled a few feathers because I dare to be "different." When I made the original post, I did not think I needed to offer an explanation as to "why" I wanted to do the conversions, but some think otherwise, so here goes: I frequently use multiple platforms to plan and check routes. Sometimes the Lats & Longs shown in one software need to be transferred to another or a chartplotter--or waypoints from a sailed route need to be moved into my planning software tools. Maybe some do not find this tedious work, but I do. All I am seeking is a tool that will do these conversions easily.

[sailorchic34]

Originally Posted by JohnT

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

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. Oddly, no need to change whats not broken.. Much like the British still use the pound and not the euro. Not to mention that we're a pig headed lot.


To the OP, just divide seconds by 60 and you have it in decimal minutes. By the same token, multiply decimal minutes by 60 to be seconds of arc.

[Tx J]

Originally Posted by F51

It doesn't matter what the standards are if the data you are dealing with does not conform to the standard. I thought mine was a simple question that might elicit a simple answer, but apparently I ruffled a few feathers because I dare to be "different." When I made the original post, I did not think I needed to offer an explanation as to "why" I wanted to do the conversions, but some think otherwise, so here goes: I frequently use multiple platforms to plan and check routes. Sometimes the Lats & Longs shown in one software need to be transferred to another or a chartplotter--or waypoints from a sailed route need to be moved into my planning software tools. Maybe some do not find this tedious work, but I do. All I am seeking is a tool that will do these conversions easily.

I thought it was a simple question too, F51.
Too many around here don't read things carefully and think to reply from the questioners reference POV, IMO, before 'assuming' (not meant to be 'snarky, but to urge a slight reflection before a 'shoot-from-the-hip' response ).

Anyway, for anyone interested, the "Martindale" engineering website contains links to almost every general, technical and engineering calculator, tool, and reference information known to man (that is not hyperbole, I've been using it since the dawn of the internet). As good as it is, few seem to know of it.

Martindale link (don't get lost in there ):
Martindale's Calculators On-Line Center

You wanted a navigation tool, lots of them here:
Martindale's Calculators On-Line Center: Part I:I-N - Navigation - Databases, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc.

And specifically a lat/long conversion one. This one accepts any L/L input format and outputs all/most of the others at once (online, it may have a downloadable app available too), likely exactly what you want:
Online geographic coordinate converter

Enjoy

Example conversion (showing too much from the dropdown menu structure, but you can see the result at bottom):

Online geographic coordinate conversions using the GeoConvert utility
Location (ex. «33.33 44.4», «33d19'47"N 44d23.9'E», «38SMB4488», «38n 444000 3688000»):


Output zone:
Match input or standardStandard UPS/UTM zoneUPSStandard UTM zoneUTM zone 1UTM zone 2UTM zone 3UTM zone 4UTM zone 5UTM zone 6UTM zone 7UTM zone 8UTM zone 9UTM zone 10UTM zone 11UTM zone 12UTM zone 13UTM zone 14UTM zone 15UTM zone 16UTM zone 17UTM zone 18UTM zone 19UTM zone 20UTM zone 21UTM zone 22UTM zone 23UTM zone 24UTM zone 25UTM zone 26UTM zone 27UTM zone 28UTM zone 29UTM zone 30UTM zone 31UTM zone 32UTM zone 33UTM zone 34UTM zone 35UTM zone 36UTM zone 37UTM zone 38UTM zone 39UTM zone 40UTM zone 41UTM zone 42UTM zone 43UTM zone 44UTM zone 45UTM zone 46UTM zone 47UTM zone 48UTM zone 49UTM zone 50UTM zone 51UTM zone 52UTM zone 53UTM zone 54UTM zone 55UTM zone 56UTM zone 57UTM zone 58UTM zone 59UTM zone 60 Output precision:
100km 1d10km 0.1d1km 0.01d 1'100m 0.001d 0.1'10m 0.0001d 1"1m 0.00001d 0.1"100mm 0.01"10mm 0.001"1mm 0.0001"100um 0.00001"10um 0.000001"1um 0.0000001"100nm 0.00000001"10nm 0.000000001"1nm 0.0000000001"0.00000000001"

Select action:


Results:

input = 87:37:39 32:39:52
lat lon = 87.62750 32.66444 (87°37'39.0"N 032°39'52.0"E)
UTM/UPS = n 2142183 1778224
MGRS = ZBE4218378224

[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!