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Guiding a C8 Fork Mount

Started by reichmat, 09/09/2010 01:17PM
Posted 09/09/2010 01:17PM Opening Post
Hey guys. Has anyone ever tried guiding with a Fork Mount? I have a Celestron C-8 with a powerstar PEC. It has the dec motor and very slow stepper motors. I got a st-4 converter box and successfully got it to connect and work with PHD guiding.

However the program loses its star after a minute or so and im not sure what im doing wrong. The motors, while slow, should be plenty fast enough to guide if run properly. I have tried playing with the settings and I think I have the pulsing length set to max. But still when the program sees the star moving in a direction, it just sends a quick pulse and then sooner or later the star just takes off in the other direction leaving me with awful star trailing.

I guess im looking for someone who has heard of this being done or done it themselves. Maybe one of you more experienced guys have some words or wisdom! I don't want to have to break down and buy a GEM! Any help or advice is appreciated.
Posted 09/09/2010 02:35PM #1
Matthew Reiche said:

Hey guys. Has anyone ever tried guiding with a Fork Mount? I have a Celestron C-8 with a powerstar PEC. It has the dec motor and very slow stepper motors. I got a st-4 converter box and successfully got it to connect and work with PHD guiding.

However the program loses its star after a minute or so and im not sure what im doing wrong. The motors, while slow, should be plenty fast enough to guide if run properly. I have tried playing with the settings and I think I have the pulsing length set to max. But still when the program sees the star moving in a direction, it just sends a quick pulse and then sooner or later the star just takes off in the other direction leaving me with awful star trailing.

I guess im looking for someone who has heard of this being done or done it themselves. Maybe one of you more experienced guys have some words or wisdom! I don't want to have to break down and buy a GEM! Any help or advice is appreciated.

The speed of the motors has nothing to do with it. I've guided plenty of older scopes both manually and with an autoguider.

What matters? Balance is critical. Make sure you are slightly east heavy.

Polar alignment. You don't necessarily need to drift, but you need to be close.

Settings. You need to play around with them to optimize performance. You do not mention whether or not your calibration is completing successfully either; if it is not, you will never guide properly.


Uncle Rod

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