I believe "DMS" stands for Degrees, Minutes, Seconds and "DDM" stands for Decimal Degrees Minutes.
You can Google these terms and find several converters for typical mapping coordinates.
what is dms and ddm i saw it on a map of fish attractors for taylorsville lake thanks in advance for any help
Last edited by dannyr3_8; 02-23-2017 at 01:30 PM.
I believe "DMS" stands for Degrees, Minutes, Seconds and "DDM" stands for Decimal Degrees Minutes.
You can Google these terms and find several converters for typical mapping coordinates.
"Both politicians and diapers need to be changed often and for the same reason" President Ronald Reagan
Proud Member of "TEAM GEEZER"MidMsAngler, NIMROD LIKED above postdannyr3_8 thanked you for this post
It's two of the three ways of writing lat. long. coordinates. Think of it like metric versus imperial measurements. DMS is written as Degrees, Minutes, Seconds or 40° 5' 18" N or spoken as 40 degrees 5 minutes and 18 seconds north. DDS is written as Degrees and Decimal Minutes where the Seconds are converted to a decimal. So the same position as above would be written as 40° 5.3' as the decimal can be carried out further than Seconds DDM is slightly more accurate. From here you can convert the decimal minutes to Decimal Degrees, the most accurate position. Where 5.3' would equal .08833°. Giving you 40.08833° N
If you start at 5' 18" you divide 18" by 60 (the number of Second Degrees in Minute Degrees)
18/60= .3 - So 5.3'
Then do this once more for Decimal Degrees
5.3 minutes divided by 60( the number of minutes in a degree)
5.3/60= .08833°
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Last edited by MidMsAngler; 02-23-2017 at 03:06 PM.
Close. DDM stands for Degree, Decimal Minutes. In this mode, instead of seconds you just have minutes as a decimal number. For example in DMS you'd have 31 degrees 15 minutes 30 seconds or 31°15'30". The same coordinate in DDM would be 31 degrees 15.5 minutes or 31°15.5' since 30 seconds is 0.5 minutes. The third common format is DD which is just decimal degrees. There you'd have 31 degrees plus .25 degrees from the 15 minutes and then another .00833 degrees for the 30 seconds which gives you 31.25833
Danny ... here's the conversion site I used : GPS Coordinate Converter, Maps and Info
But, I "had" to use it back a few years ago, because the KDFWR Fish Attractor site only gave one version of GPS coordinate readings ... DDM
Now they offer 3 different versions : GPS - DMS - DDM
I had to use the conversion site because my Lowrance Elite 5DSI would only accept the "GPS" version numbers of the conversion site. If I put the DDM numbers in my unit, my waypoints were in the desert somewhere in the Middle East (not all the numbers would fit, so I left off the last digit, thinking it was measuring "inches" ... because I didn't know what I was doing, never having had a unit that had GPS capability)
thanks to all, man i had no idea having gps would create a need for so much math might have to sell it
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Depends on the model of FF/GPS unit you have. You might post make/model and someone may help you out more.
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Some interesting GPS information.
0.00006 minutes of difference in latitude is about a half a foot. Consumer grade GPS is not very accurate. My experience is that on a good day accuracy is hardly ever better than ten feet and shouldn't be expected to be better than ten meters. This is an especially important when trying to find a point you established days or months earlier because as the satellite constellation changes retracing is more difficult. Trees and rock cliffs can effect accurately in unpredictable ways. Most dedicated GPS units can download assistant GPS data from the internet. This data is generally referred to as A-GPS data which tells the unit where the satellites are. If your unit does not have this capability you should turn your unit on ten minutes before using to acquire an initial fix.
There is an intentional degradation of GPS location to prevent it being used by other militaries. Survey grade GPS gets around this by sitting on a point for several seconds and using an averaging algorithm. Additionally accuracy is added by post processing using data the government publishes. At one time the introduced error was even greater preventing real time survey but the government dropped the location error and now the error would only effect something like a missile travelling at high speed.
GPS is fun and amazing stuff we should not take for granted.
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