H20 C Accuracy

[lureman]

Recently purchased an H2O and while experimenting came across an accuracy question. When exchanging waypoint coordinates with a friend we where finding the waypoints not showing in the prop er location on the map. What we determined is that his GPS on his boat was set to read coordinates using degrees/minutes/seconds my H2O is defaulted to degrees/minutes. As I previously mentioned when I provided him coordinates from my H2O or my old Garmin the points were not accurately located on his unit. He switched his unit to read degrees/minutes and the waypoints then showed up in the proper locations. My question is does one option provided a higher level of accuracy?

My interest is getting as accurate as possible so to easily locate breaklines and structure when ice fishing. Drilling numerous holes in 46 inch ice is tough on this guy! Any comments or suggestions on how to best dial in an H2O would be appreciated. I sometimes find the owners manual not having all the dirty details.

[DEADhead]

the degree minute format that utilizes decimal point places, seems to be more accurate on getting on top of a specific spot. I've found that it is more "precise" than using degrees minutes and seconds, or UTM coordinates.

[Fish&Fowl]

That's interesting I will have to check mine again to see what setting I'm on. It technically shouldn't make a difference but I can see how it would. I have also noticed better accuracy on larger bodies of water as opposed to small ones (in most cases).

[PerchJerker]

Quote:

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My question is does one option provided a higher level of accuracy?

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No, one format is not more accurate than another. When your waypoints are in there, they will not "move" when you change formats. You can test this yourself by looking at a waypoint on the map, then changing formats, then rechecking the map. Your waypoints will still be there.

If you take the numbers from one format and just key them into another format, you are really entering different coordinates. You would either need to convert them to the new format and enter them that way, or you would need to change the format in the gps and then enter them. Changing the formats is easy, it's just a couple button pushes on the menu.

[Surface Tension]

You both need to be using the same format when exchanging coordinates. As far as which foramt is better I don't know if one is better then the other.

Onto another H2O subject, there was a post a long time back about the H2O and accuracy. The H2O's EPE was fine but the data on the lake maps was way off. Anyway there was a procedure to zero back in. I don't recall that procedure, anyone?

[McGurk]

In Degrees/Minutes/Seconds format (DMS) most handhelds have the coords entered as such

Deg-Min-Sec Deg-Min-Sec

N00 00 00.0 W00 00 00.0

with the minutes being split into 60 increments and the seconds being split into 600 increments (60x10) for a total of 36000 increments (60x600).

In the Degrees Decimal format (DD) the coords are entered like this:

Deg-Min----Deg-Min---

N00 00.000 W00 00.000

with the Minutes being split into 60,000 increments (60x1000).

That being said, the DD format is inherently more accurate on paper. The fact of the matter is with handheld accuracy usually being +/-20 feet (best I've seen is +/-7 feet personally) you aren't getting the ability to approach the accuracy of the DMS format's abilities, let alone DD's format.

Long story short, the 2 formats' inherent accuracy are better than your handhelds accuracy (your data is better than your equipment). You need to pay more attention to the formats for transferring data from unit to unit or PC to unit, and make sure they are all the same one, either DD or DMS. Pick one, I like DD personally.