Cannot Guide

ernie.si...@gmail.com

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Jan 9, 2022, 12:52:59 PM1/9/22

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I have an Ioptron GEM28 mount and a QHY CCD camera for guiding and cannot guide. The mount will move when instructed by the PC so obviously something is incorrect in my settings. Would appreciate some advice. Log file is attached.

Thanks,

Ernie

PHD2_GuideLog_2022-01-09_145207.txt

wave...@talktalk.net

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Jan 9, 2022, 4:28:41 PM1/9/22

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Hello Ernie, I'm no expert, but reading your Guide Log headers raises a few questions in my mind. You appear to have an SCT operating at prime focus with the guide camera attached with off-axis guider and connected to the mount by an ST4 cable. Is that right? If so, you're going to find guiding at an image scale of 0.15 arcsec/pixel very challenging, with the inconvenience of having to re-calibrate for each target you visit. You don't appear to have installed an ASCOM driver for the mount which will almost certainly limit your capabilities. However, if my conclusions are way off base, then you've not set up the PHD2 profile correctly.
I'm sure someone with a deeper insight than mine will be along soon to give more advice.
Cheers,
- Jack

ernie.si...@gmail.com

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Jan 10, 2022, 6:20:31 PM1/10/22

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could someone jump in and help? Would be grateful...

Ernie

Ken Self

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Jan 10, 2022, 8:31:35 PM1/10/22

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If you are controlling the mount from your PC, then why bother with ST4 guiding? ST4 cables are notoriously unreliable and in PHD2 you get very little data for analysing issues like this.

So start by selecting the appropriate ASCOM driver for your mount in PHD2. When you do this, create a new profile with the wizard to make sure everything is properly set up.

Aimee Paradise

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Jan 11, 2022, 6:49:13 PM1/11/22

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Thanks! What setting should I choose for PHD2 for the telescope mount?

Rick Cohen

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Jan 11, 2022, 6:54:44 PM1/11/22

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in PHD2 pick "iOptron CEM120/70/40/26, GEM45/28 Mount (ASCOM)"

mj.w...@gmail.com

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Jan 12, 2022, 5:17:20 AM1/12/22

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Hi Ernie

Bin the Guidecam as much as you can to give a more reasonable image scale.

And that will improve sensitivity too, which is often necessary with an OAG, I see you were getting "Star Lost" messages.

Currently it's 0.15arcsec/pixel, x3 would make that 0.45arcsec/pixel.

Also build a PHD2 Dark Library for the guidecam.

Michael

Wiltshire UK

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