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Old 22-04-2019, 08:24 PM
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Dark sky rules !

skysurfer is offline
Join Date: Dec 2011
Location: 52N 6E (EU)
Posts: 1,150
It depends on more factors.

* Focal length
* Mirror surface height above the ground

So eyepiece height is FL-Diameter/2+height above ground.

Mine (also 16") is 1800mm (f/4.5) and mirror is 20cm above the ground when pointer vertically, so it is 1800 - (400/2) + 200 = 1800mm = 1.80m.
And my eyes are 1860mm above ground (I am 1.96m) so I can almost observe objects near the zenith while standing, but for objects below 60 I have to bend or use an observing chair.

Shorter people have to use steps when observing near the zenith.
When that is a problem, get an f/4 16" Dob which has a 20cm shorter FL, but most eyepieces require a coma corrector.
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