QHY5 guider with CGEM and PHD

[Gem (Grant)]

Hi all,

Does anyone else out there use this combo? I can't get it to work yet. I can get the calibration done fine in PHD - but then it keeps losing the star afterwards and not guiding. I have the QHY5 camera connected to the mount and "on camera" selected from the mount menu in PHD.
Next clear night I will try it using ascom and the laptop connected to the mount via usb/serial adapter and the cable that came with the scope. I have downloaded ascom and the drivers for CGEM and QHY5. The only possible problem might be the terrestial prism on the guide scope that inverts the image - but I need a focal extender tube with it.

Anyway... if anyone has the same combo and knows of similar issues - please let me know.

[mswhin63 (Malcolm)]

It is possible the exposure set for the camera is not enough for the star you are guiding on. I had this experience for a while when I finally decided to learn how to use PHD to the fullest. I don't use QHY but instead a webcam and the performance of the QHY should way outperform the webcam.

The process I use to increase the slider (exposure Control) to the left or max. take a dark. If I see a star easily when selected great. If not I increase the time up increments till I see one. You have to take a dark shot every-time you change a setting.

If anyone has an alternative, I will be happy to know as well as I have only used PHD for a short time.

[Marke (Mark)]

I could only get my cgem to guide with GBUSB via laptop and not thru the cgem guide port.

[lepton3 (Ivan)]

Not exactly the same setup, but I use an Orion SSAG camera (which I think uses the same sensor as the QHY5) with PHD very successfully on my CGEM. I use the on camera guide port driving the CGEM guide input.

I typically use an exposure of around 2 seconds through a 50mm finder guide scope.

Autoguide rates and backlash settings are not particularly critical, but can be tweaked to give best results, but if the seeing is good, pretty much anything works!

-Ivan

[Gem (Grant)]

Thanks all! Glad to hear some others are having similar issues.
Just need some clear sky to try some of the advice and also try using laptop to CGEM (using ASCOM) rather than QHY5 to ST4 port.