Re: [APML] Advice on guiding eyepiece

[KGKIRKLEY@aol.com]

In a message dated 1/16/02 2:31:13 PM, wclark@cdic.ca writes:

>Does anyone have any experience with the Vixen GA-4 projection reticule
>on a
>
>Schmidt.  My dad wants to get one to use on his C8 with a Lumicon Cassegrain
>
>Easy Guider.  I thought the GA-4 was mainly for guidescope.
>
>
>
>Anything I can tell him about it would be great.  Any advice?
>
>
>
>-Bill

Bill:
It is used primarily for guiding or alignment purposes.
This is a projection reticle deivce, meaning it goes in the scope drawtube 
and any focal length eyepiece goes in the eyepiece end of the device. This 
means you can use low a power or high power eyepiece. The cross-hair reticle 
is projected into the image and is moveable in X-Y, meaning if a star is in 
the field of view, you move the reticle cross-hair image to the star, instead 
of having to move the scope. The X-Y orientation can be rotated to line the 
X-Y axis' with RA and DEC. The illumination can be adjusted.

One thing to be careful of. If used with an OAG, there might not be enough 
backfocus to use this device, because the optical path is long, as in a 
diagonal, which it actually is.

Other than that, these projection reticle devices are wonderful tools.

Kent Kirkley

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