Technology Question

[apb]

I would guess that if you had GIS software (Arcmap or something similar) and access to DEM's for the area you could do something like you suggest. I'm not familar with GIS to know for sure. I'll see if I can found out a little more from someone at work on that.

Andrew

[rickhise]

let me ask you this, if you mark a spot, for sake of imagination a pile of rocks the size of a car with a high end handheld gps, and you have gotten your gps coordinates with the utmost diligence possible.

now you give these coordinates to someone else, what do you say is the closest someone else can come to this using a handheld gps of the same quality.........

the reason I ask is we do some geocaching (sp) and they figure one gps may vary as much as 30 ft. and a second gps may do the same so your target may be as much as 60 ft. off......is this true ??

not trying to jump on your post but always curious as to how close one can pin point a spot with gps

[apb]

It will depend on the acuracy of your GPS unit each day. Your unit should provide a +/- reading on it so you'll know what the error rate is. A GPS unit will put you in the area, but usually not right on top of the spot you marked. That is why I would never rely solely on any GPS unit to run and high speed on a lake. That and the GPS does not show the other boats on the water.

Andrew

[smashdn]

yeah what apb said about accuracy. The clearer the day and the more satelites you can pick up the more accurate the reading. It only takes three to triangulate your position but having four or five at your disposal is so much the better.

As far as your rock pile scenario, first off why are you giving away fishing spots? No, seriously though if you mark something with gps and you have a good quality signal both times you should be able to get within 5 feet of your spot every time. If you are within 5 feet nad going slow enough, assuming adequate depth of water, you should be able to see what you are after on with your fishfinder cone.

[rickhise]

the gps forums dont give you much of a chance under 30 ft. locating a spot with cordinates using ideal conditions...

the reason I posted the question 5 of us sunk huge xmas trees and other structure, and did the best we could to pin point the location so when we were done each of us could give the other the best possible means of locating the structure........so with the flasher along with the gps info.........should be simple enough.........

the 2 we did the year before produced a lot of crappie