I don't think you have a problem...I've seen this behavior often under two
circumstances:

(1) your tube is not yet cooled to the ambient temperature outside (this is
the most frequent cause) and/or
(2) you're observing nearby an obstruction such as an intervening tree
branch which is causing the spiking.

I'd recommend waiting at least an hour to an hour and a half outside for
the tube to clear, then trying again.

Charlie Wiecha








cc:

Subject: [M]: Optical Problem?


Last night I was out with my 8" LX50 peeking at Mars and the Moon. I swung
over to
Arcturus and was looking at the diffraction pattern at about 300X and
noticed something.
The rings of this slightly defocused star were distorted in one section.
>From about the
11 o'clock position to about the 9 o'clock position (as I viewed in my
e.p.) the rings were
near perfect. Then they seamed to form two spikes diving into the center
of the pattern
and flaring outwards at about the 9:30 and 10:30 positions. The spikes
were narrow and
flared out about 20% further than the outer difraction ring. It looked
like horns coming
out of the star. This was much more obvious when I was couterclockwise out
of focus
then when I was clock wise out of focus (of course, when I was clockwise
out of focus
the patern was on the other side). I rotated the eye piece and the pattern
did not move,
so I think that means it's in the telescope, right?

This is the first time I have noticed this. Is this because I am becoming
a better observer
and am just now noticing this feature, or could it be a new defect? If it
is new, what
might have caused it? Can it be fixed? Does it need to be fixed? How
much am I
loosing by having this defect? I don't have a web page, so I can't post a
drawing of what
I saw, but if this sounds familiar to someone I'd apreciate a reply.

Thanks,
Phil Freeman

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