Re: [APML]: guider/reticle problems

[aa6g@aa6g.org (Chuck Vaughn)]

Robin,

>I am having trouble seeing stars of 6th magnitude and fainter in an
>Orion OA guider, an Orion chord powered 12mm Kellner illuminated
>reticle, on a 7" Maksutov LX200. The LX200 controls the brightness of
>the reticle. At the dimmest setting, the glow from the illuminated
>double cross hairs obscure most stars.
>
>My question is, where is the cause of the problem, and is there a
>solution?
>
>1) Is this just the normal situation with off axis guiding?

I've found any illumination interfers with seeing faint stars somewhat
but a 6th magnitude star should be quite bright and not a problem.
Perhaps there is far too much illumination. It should be just bright
enough to make the crosshairs red.

>3) Should I try to further dim the reticle with filters in front of the
>LED, or a resistor in the line?

You certainly could try adding a resistor in series with the LED to dim
it. You might want to start with a 100K ohm pot to determine the proper
value.

>5) Should I just bite the bullet and get an SBIG guider?

If you do enough astrophotography you'll end up with one. :-)

Chuck  <aa6g@aa6g.org>