GPS co-ordinates

GPS co-ordinates

Hi guys,

just a little tip. I noticed during registering new users, that often people specify their GPS co-ordinates to for example 1 decimal place. At first sight this might seem ok, however what one must realize is the size of the Earth and the potential error in this.

To give you an idea:

1° latitude = approximately 111km (69 mi). So even 2 decimal places means a difference of +/- 11 km (6.9 mi).

This is important for calculating sunrise/sunset times etc.

I would therefore highly recommend using 4 decimal places. I have also seen opposite extremes, people sending me their GPS down to 12 d.p. 😀 Which is funny, it would be microscopic distance 😀

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