From: "hpholcomb" <hpholcomb@yahoo.com>

Date: April 7, 2008 5:32:10 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: Guiding Celestron mount?

Alen and Milton,

The following could be an alternative solution for guiding the mount.

Download the rather short .pdf from Shoestring Astronomy, the source

for the GPUSB (shoestringastronomy.com) that Milton mentions:

"Modification of a EQ-style Dual Axis Controller to Add an Autoguider

Port"

This mod doesn't install a serial port but an RJ12, which has become a

de facto standard port for guiding because of the earlier SBIG ST-4. 

If one is running a PC without a USB port, then a serial-to-USB

adapter would also be needed.

This mod makes for a rather inexpensive autoguider as compared to the

cost of some of the OEM trackers/controllers/motors etc.  I'm no

electronics expert, but I wouldn't fear making this mod to my

Celestron 4-button dual axis controller for the CG-4 EQ mount.  In

fact, it's quite simple and well explained with accompanying photos.

Perry

--- In Astro_IIDC@yahoogroups.com, Milton Aupperle <milton@...> wrote:

Dear Alen;

No it is not possible to guide using a celestron mount via a serial  

port with Astro IIDC. The Celestron protocol for controlling the  

mount does not have any means of saying "move 1 second west and 0.2  

seconds north" and you have to tell it move it as an absolute  

location (Ra Hour Minutes, Dec Minutes seconds). So you'd have to  

have the scope calibrated with 3 stars before it would work, and even  

then it doesn't work very accurately (+/- 1.0 arc seconds).

However we can guide with a Celestron type mount (i.e. CGE /  HEQ5 /  

HEQ6 / Orion Atlas / Orion Sirius) using the ST4 Auto guider port and  

a GPUSB box from ShoeString Astronomy :

http://www.store.shoestringastronomy.com/products_gp.htm

and Astro IIDC.

HTH..

Milton Aupperle

On 7-Apr-08, at 6:57 AM, alien2108 wrote:

Hey!

Am I wrong or is it really not possible to autoguide Celestron mounts

(CG-5)? It does connect, but immediately after connection my mount

starts to move. After I stop it with HC, controls in Astro IIDC

doesn't work?

BR,

Alen