[geeks] laser for pointing out stars

[Francois Dion]

On Wed, Sep 3, 2008 at 5:31 PM, Barry Keeney <barryk at chaoscon.com> wrote:
> On Tue, 2 Sep 2008, Francois Dion wrote:
>> I need a green laser pointer for pointing stars so that a group of
>> people can quickly identify which I'm talking about.[...]
>  I do astronomy as a hobby and I use two 5mw green lasers for the
> star parties my local club runs. One is mounted on my telescope, the
> other I hold to point out stuff.

You just doubled my cost! Astronomy is like photography. You start out
with a relatively small purchase and end up spending a ton :)

>  The scope mounted one comes in handy to show people where the telescope
> is pointed and to find stuff. I made my telescope and it doesn't have
> any computer/tracking system to find objects, I star hop to find stuff.

Sounds like a good idea. I was thinking of adding one and or a
viewfinder on my ETX. Kind of like this one:
http://www.weasner.com/etx/techtips/2007/finderscopes.html

(This guy has a 240mW (!!!) green laser pointer. That is a bit extreme to me...)

The ETX dont have a viewfinder, which I find annoying. I also made a
scope out of russian surplus optics, t mount adapters etc. It's ok as
a land scope, but for astronomy I would need a 90 degree mirror.

>  The 5mw should be fine most of the time. If the sky is clear, calm,
> and dry it might be a bit hard to see the laser but that will be true
> no matter the power of the laser. Got to have stuff for laser to
> bounce off of to see the beam.

Ok. So which one did you get, they have several. I was also looking at
this one right here to use as a pointer:

http://www.instapark.com/category/laser-products/lg-10.php

whereas a slimer one would probably be easier to mount on the ETX.

Francois