GUIDESCOPE Last updated: 6 November 2002

Subject:	Photography : Semi-autoguiding 
Sent:	Monday, November 4, 2002 19:50:05
From:	vergot@adelphia.net (Adrian Vergot)
Even though the ETX motors in general have a lot of slop with respect to
guided photography, the ETX-70s wide angle 350mm focal length should be
fairly forgiving.  Subsequently, I decided to try setting up a pseudo
autoguider since I hate hunching over a reticle eyepiece worrying about
bumping the scope.  Below is a photo of the assembly, though a simple
cheap black and while TV set would do just fine in place of the laptop
PC simply get a guidestar on the TV screen, draw a tight circle around
it with a dry erase maker (if using a PC, simply place the tip of the
mousepointer directly on the star image), and using the ETX paddle
buttons keep it centered within the circle (or on the mouse pointer...).
I have included my first test picture of the Orion Nebula, taken at
prime focus with a nebular filter for 5 minutes using Fuji-Superia800
film.  On a side note, the video camera and Quantaray lens perfectly
offset balance the OM1 camera, so that no counterweights are
necessary...

8^)
Adrian

ETX-70
SuperCircuit .0003 lux C-mount video camera
C to T mount adapter (Orion Telescopes)
Quantaray 500mm Mak T-mount lense (Ritz Camera)
PC with video-in
Battery Pack
OM-1

Return to the top of this page.

Go back to the Astrophotography Page.

Go back to my ETX Home Page.