Re: Digital Photography On Aircraft Not Permitted on Take Off or Landing

In article <5v1pbjF1jnvqnU2@xxxxxxxxxxxxxxxxxx>, Chris Malcolm
<cam@xxxxxxxxxxxxxxxxx> wrote:

i have its predecessor, the 60cs, and there is *no* way to disable it.
it's annoying, because the displayed altitude is nowhere near accurate.
i've even driven underground for many miles. :) because of that, i
will not be getting a gps that has a barometer in the future.

Garmin GPS units with barometric altimeters are capable of providing
more accurate results than GPS altitude, typically moving from GPS
altitude error being about twice as bad horizontal error, to being
twice as good. That's why they provide the feature.

in theory. in practice it's very *inaccurate*.

But only if you're
prepared to learn how to operate it properly. If often requires a
rather fiddly process of calibration. If left alone and expected to
work completely automatically it will often produce huge errors.

what a crock. i was driving on level ground one time and the weather
suddenly changed. the gps indicated that my altitude dropped from a
little above sea level to a few hundred feet below sea level. was i
supposed to pull over and obtain a weather report and recalibrate the
gps?

with an external antenna on my car, i typically receive 8-10 satellites
so the accuracy should be *very* good. i often have a lateral error of
about 5-6 feet, and i can even see where i made lane changes on maps.
as far as the gps is concerned, i do that underground. :)

and on airplanes, it always reads 6000 feet, regardless of altitude,
and no apparent way to shut it off.

my next gps will *not* have a barometer unless there's some very clear
way to disable it and use the gps satellites.
.

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