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Thread: Problem with Google earth

  1. #1
    Member tboehm's Avatar
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    Default Problem with Google earth

    Just wondering if anybody else is noticing this. Got some coordinates for my pilot on a drop off plug them in on Google earth and it's actually showing 3.85 miles off of where it actually should be. Did the same thing with the in reach and it's off on that map as well. Finally plugged it into my Garman GPS and showed exactly where it should be. This can cause a lot of problems trying to plan our hunting spots and marking locations.
    Semper Fi and God Bless

  2. #2
    Member ChugiakTinkerer's Avatar
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    It may be how the coordinates are read off and/or input. Is everything in decimal degrees or do you have some minutes and seconds being interpreted as hundredths and/or ten thousandths?

    For example, Long Lake at the headwaters of North Fork Campbell Creek is at about
    6107'32.0"N 14933'00.0"W


    If I key that as decimal degrees I get 61.07320 N, -149.33000 W. That puts it at a point about 6 miles southeast of Long lake.


    Is it possible this is the sort of issue you've encountered?

  3. #3
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    Make sure the datum is the same in both devices

  4. #4
    Member sayak's Avatar
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    I was thinking that the problem with Google Earth is that it lets everybody else see all the secret places you see.

  5. #5
    Member ChugiakTinkerer's Avatar
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    Wrong datum is usually good for about 200 yards differential. Not on the scale of the problem tboehm is seeing, but another thing I frequently forget is that the imagery in Google Earth is not usually orthorectified. So being off a few tens or maybe even hundreds of feet is within the range of normal.

  6. #6
    Supporting Member iofthetaiga's Avatar
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    There are places here where the difference between NAD 83 and NAD 27 can put you over a ridge and into a completely different drainage.... So ensuring you're using the same datum is important.

    That said, your pilot's GPS is likely displaying DEGREES - MINUTES - DECIMAL MINUTES, and confusing that with DEGREES - MINUTES - SECONDS can throw you off a fair piece too.

    The third format option is DEGREES - DECIMAL DEGREES, but typically that is not used in general aviation.
    ...he who knows nothing is nearer to truth than he whose mind is filled with falsehoods & errors. ~Thomas Jefferson
    I would rather have a mind opened by wonder than one closed by belief. ~Gerry Spence
    The last thing Alaska needs is another bigot. ~member Catch It
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  7. #7
    Member hogfamily's Avatar
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    Default

    I prefer ACME Mapper.

    http://mapper.acme.com/

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