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Old 13-08-2013, 11:51 AM
celstark (Craig)
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celstark is offline
 
Join Date: Nov 2008
Location: Irvine, CA
Posts: 17
Quote:
Originally Posted by Star Hunter View Post
So does one have to actually connect a mount to same PC/laptop so PHD can 'handshake' with the mount? I thought all this was done through the autoguider cable between guider camera and the mount's guider port.
PHD's code figures the current error in RA and Dec and then tells the "mount" how long to fire the motors. The "mount" is, to PHD, a fire-and-forget device. It can send that message to:

-- The port on the camera (if it exists)
-- ASCOM
-- A GPUSB or other USB->ST4 device
-- A parallel port

Where it sends the message is dictated by your choice in the Mount menu (see here for a walkthrough)

Now, if you send it to the guide port on the camera (the ST4 port) and you've not got a cable going from there plugged into the mount (as you think you're guiding through the serial cable that's also hooked up), you're not exactly going to guide well. Likewise, if your mount hasn't been told to listen to the ST4 port (e.g., a Gemini in "visual mode"), no commands will get through. Or, if you've got an ST4 cable but it's the wrong style (straight vs. reversed). All these, will lead to the motors never going on.

So, trace through where PHD is sending the commands and make sure that things are really setup to let those commands get through. Most of the time, PHD's got no way of knowing if those commands were ever received.

Craig
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