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(meteorobs) (ugradert) Re: Tunnel vision & wide angle perception

On Fri, 23 Aug 1996, George Zay wrote:
>> do you center your view at 0-20 degrees from zenith due to perhaps a
>> sky glow during the night around your horizon?  If I'm picturing this
>> right, would there seem to be a perpetual dawn at your latitude at
>> this time of year?

Hi George, sorry for my late answer.

Sky glow / perpetual dawn:
Yes, the sky is never completely dark around Perseid maximum.  Full
darkness comes around august 18th.  There is a notable difference
between a few days before and after the 18th.  Anyway, the entire
horizon does not shine with a faint glow (it does in June, but not
in August).  In August, all I can see is a thin and very faint glow
above the northern horizon.  The rest of the sky is (appears to be)
completely dark.
Last night I observed Jupiter.  The seeing was horrible, since the
planet does not rise more than 7 degrees above the southern horizon.
A couple years ago, when the Moon reached declination -28, it was
only about 2 degrees above the southern horizon.  Even a full moon
did not reduce ZLM to any worse than 6.0 or 5.5.


Center of field of view:
I guess the main reason is that I feel more comfortable with it.
I like to center my eyes in the exact direction of my face.  Since I
observe lying on a camping bed, it is difficult to direct the face
to an altitude of 30-40 degrees from zenith.  If a raise my bed so
I can look 40 degrees from zenith, I would simply slide down from it.
I tend to slide down because I always observe in a sleeping bag,
and the sleeping bag is slippy.  I always observe in a sleeping bag
because it is practical.  It is practical because then I won't have
to dress like a marsh-mallow (spelling?) against the cold.  Night
temperatures are typical around +7 Celsius, always with humidity
because the temperature drops a lot from daytime, this adds to the
chill.  I _have_ observed in temperatures around 15-18 degrees.
Then the air is very dry, and it's really too warm to stay in the
sleeping bag.  Such nights are very rare, especially in August.
So, that's the long story of my viewing direction.  :-)

All the best,
Trond