Re: Starhopping, star-strolling, and star-drifting?


"Margo Schulter" <mschulter@xxxxxxxxxxxxxxx> wrote in message
news:46dd1912$0$30973$d368eab@xxxxxxxxxxxxxxxxxx
Hi, everyone, and recently I've been considering some
possible strategies for observing with a Dobsonian

The classical strategy, of course, is starhopping,
and maybe the other two I'm going to sketch out here
are simply variations on that; in fact, I've seen
one form of the second ("star-drifing") mentioned
as an approach for finding objects.

I could be wrong, but I believe that drifting is a practice for a polar
aligned mount. You look up the RA and Dec of the target, then set the Dec
setting circle (which is fixed to wrt the mount) and sweep (drift) east or
west. This allows you to look for the object in a single east/west motion,
without having to fuss with your RA setting circle. Coincidentally, from my
latitude, if your altazimuth mounted scope is aimed at M22 when it is east
of the meridian, M8 is just a short sweep due west in a wide field eyepiece.

In what I might call classic starhopping, there might
typically be lots of guidestars easily visible to the
naked eye, or at any rate in a finder scope.

Not sure what you use for finding, but one of the best things you can do for
yourself in light polluted skies is to get a Telrad and a 9x50 Right Angle
Correct Image (RACI) finder. For areas of the sky that have enough bright
stars, the Telrad is all you need (and under dark skies). For areas that are
sparse in bright stars, the Telrad can be used as a simple unit power
"gunsight", and then the RACI can be used with the star atlas without any
mental or physical gymnastics.


Also, from the descriptions I've read so far and a
bit of experience (more confident with binoculars
than with my 20cm f/6 Dob), I'd take it that classic
starhopping often implies moving from one object of
interest to another over distances considerably
greater than the field of view (FOV) of the eyepiece
in use, with the destination as the main interest.

Maybe defined a little differently (for better or worse), it is the process
of using one star as a jump point to get you to the next star, and hopefully
to a non-stellar object nearest the final star in the hop. It doesn't
require an eyepiece in the main scope at all. It can be done with just a
Telrad. However, some guidebooks will take you an a widefield eyepiece field
to field journey if you are so inclinde.

IIRC, it was Sketcher who once defined his favorite method as PAL (Point and
Look). :-) That process is mode more possible with a Telrad.

Enjoy!
-Steve




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