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Unit finder for light polluted area

Started by adamsdp, 01/21/2007 08:02PM
Posted 01/21/2007 08:02PM Opening Post
If anyone has any thoughts or opinions on using a dob with a unit finder only from a light polluted area they will be appreciated. I am purchasing a 8" Starbucket and it has a Rigel Quickfinder. The drawback I can see is that in some areas of the sky, the light pollution washes out even the constellations so it is hard to get a star hop going without some kind of optical aid. I am not sure if a RACI finder would help much or not and I would have to add a signficant amount of weight which I would like to avoid since one of the main reasons for buying the scope in the first place is to reduce the weight from my xt-8 clone (45lbs) to the Starbucket 8" (27lbs). I could put an Orion 6x30 RACI finder and maybe "only" have to add 4 pounds or so at the back end of the scope for balance. The other option I am thinking of is digital setting circles. Thanks.

Dave Adams
Posted 01/21/2007 08:28PM #1
Dave, a nice, high quality 6x30 r.a. finder for your scope would probably be suitable. I observe from a light polluted area and have found that a small finder is essential.

Darian R.
Posted 01/21/2007 08:49PM #2
Hi Dave.
I would recommend adding the finder, if I were you.
I use a Telrad, but unless I'm at a dark sky site, it has limits on it's usefulness.
I mean if you can't even see the guide stars...
The Telrad will get me in the ballpark, but when I look in the finder,
often I will immediately see the target off to one side.
It is then easy to center it up.
At this point though, I must admit to having DSC's as well.
For the more difficult objects, I just rely on my Sky Commander. wink
But it's really nice to have the options.
Linton
Posted 01/21/2007 09:09PM #3
Dave:

I do most of my observing from a light polluted back yard. In my experience a magnifying finder is much more useful than a unit power finder for the exact reason you state, there are not enough guide stars to accurately point a telescope.

I prefer either a 6x30 or 8x50 straight through finder as I can see suffient guide stars as well as allowing me to use the "both eyes open" technique. With both eyes open, one naked eye, one through the finder, I can see both the unmagnified view with its guide stars and the cross hairs plus the magnified field of the finder. This functions much like a Telrad or Rigel but when the intended target enters the field of view, I can close the naked eye and aim the scope with the magnification. Thus a straight through finder can eliminate the need for a Unit Power finder and it is also lighter than a RACI finder.

Jon