Subject: Re: Geotagging app
In article <firstname.lastname@example.org>,
> "PeterN" <"peter,newdelete"@deleteverizon.net> wrote
> | I do it the easy way. I take a snap of the location with my iPhone. All
> | relevant information is recorded.
> For what it's worth, I got curious and looked at
> some photos a friend took at Mt Desert Island last
> year, on an iPhone 6. The lat/long seems to be
> very close, within yards. The altitude, however,
> is not so accurate. A photo of me looking at a rock
> on the beach recorded altitude 4.53 meters
> (14.8 feet). Another shot taken in the same
> spot (within a few feet on a nearly flat beach)
> shows 6.6 meters (21.6 feet).
> This photo...
> ...shows 58.84 meters (193 feet). We were probably
> 30-40 feet above the water. There may be variation,
> accounting for tides, but it still seems to be inflated
> by about 500% and/or to some extent arbitrary. How
> can it vary by 50% in the same spot with pictures
> taken a few minutes apart? I don't know. Perhaps
> different info sources? Maybe a change in cell towers
> that caused variations in location?
> It might be worthwhile to check some known altitudes
> and maybe check those against Google before depending
> on the stats. (Though I don't know what one depends on
> them for. Why does anyone care about altitude stats
> except, maybe, when mountain climbing?)
Do your iPhone have a gyroscope? If not then it's obsolete for pinpoint