Can anyone advise a guiding newbie? [SOLVED]

[billyharris72]

Hi all:

Had my first go at auto guiding last night - a long, frustrating and cold experience. I managed to connect my mount and get slewing etc working okay, and to connect the guidescope up in a way that I assume is correct (i.e. like the camera, but with the ST4 cable running into the mount's guide port also). Astroart was able to grab a frame at 2s no problem and I could select a star. That's where progress ended.

When trying to calibrate I got a message that the telescope was not moving or not moving enough, so check my connections and try again. Every so often it seemed that it would go through the calibration procedure (maybe one time in every ten attempts) but I could not reproduce this and AstroArt did not seem to be sending any signals to the mount (there were none of the little flashing arrows that you would expect to see with AA).

I tried a few times with Phd2 and had the same response. When trying to send guiding signals manually via Phd2 I think I heard the noise from the mount change slightly, so it may be that a signal of some sort is getting through (but I don't know for sure).

Two other things may be relevant:

1. I noticed Astro Art occasionally went into "not responding" mode and I had to wait a few seconds. Clearly that shouldn't be happening, but I don't know if it's a hardware thing or if AA and some other piece of software are not playing nice.
2. I have always had problems manually slewing via the game controller. I don't know if its the game pad or a USB issue. The game pad seems 100% fine when I test it, but in use it cuts out and acts somewhat eratically. No idea what has been causing this and I could see how this could affect pulse guiding, not so sure about ST4 though as I thought that was kept totally separate.

My thoughts on possible causes are:

• Hardware problem (I did swap ST4 cables so I don't think that's the issue, and also disconnected and reconnnected everything and rebooted, but it could be something more serious).
• I haven't set something up properly in EQMOD (entirely possible).
• Some kind of software clash.

Are any more experienced sould out there in a position to advise how I might go abpout troubleshooting this problem? I'bve listed my kit below in case that provides any clues.

Thanks,

Billy.

 

Laptop and software

 

• Lenova Yoga 3 running windows 10
• EQMOD - tried both pulse and ST4 settings
• Astro Art (camera control, mount control and guiding)
• Cartes du Ciel
• Phd2 (tested as alternative to AstroArt)
• Laptop connected to all hardware via Star Tech ST7300USB3B USB hub

Mount and controller

• HEQ5
• EQMOD - connnection via Hitec Astro USB adapter
• Logitech F310 gamepad

Main Camera

ZWO 1600m

Skywatcher 130 P-DS

Guide camera

ZWO ASI120m

QHY mini guide scope

[MarsG76]

You have started a journey into a deep dark place, you will have challenges, adventures, frustrations and might even think about giving up.... but remember that countless others have been where you are and have come out the other side with rewards. 

To get you scope to guide will take time and practice, and I recommend to star at short focal lengths until you start to get results.

Reading you above I kept thinking that your mount might not be responding fast enough, so make sure that your back lash is setup on the hand controller that at 1, 2 or 3 X sideral rate your mount responds immediately, or soon after you press the buttons in every direction, back and forth without any jumps. Use the camera with a star on the screen when you're testing this.

Make sure that the tracking is turned on and that the mount actually tracking the sky.

The other is make sure that you calibration pulse time is long enough for your mount to respond with the autouide software to do you calibration....I use 500ms on PHD.

Another thing is make sure that your polar alignment is within 5 arc minutes of the pole, the closer the better. Autoguiding is meant to ONLY HELP OUT a already good tracking mount and not do the tracking it self.

 

[LightBucket]

If you get the message that the scope is not moving enough to, then theclibration step size is too small and needs to be altered, the shorter the focal length of the scope the larger the step size needs to be, and the longer the focal length the shorter it needs to be. Hope that helps

[LightBucket]

Lol, posted at the same time, but as MarsG76 said....

[billyharris72]

Thanks for the advice guys. I'll start with getting backlash corrceted and trying longer guiding pulses, maybe just using phd and no imaging camera (so less chance for software conflicts) then take it form there.

Here's hoping I get another clear night before the end of 2017 to try it out...

Billy.

[LightBucket]

Its not the guiding pulse its the calibration step that need changing..

[newbie alert]

Are you getting the response that the star didn't move enough on the callibration step?

If so the slack in the DEC needs to be taken up as it will try to move the star north on its first step..after then it's fine..if it stars to work it will give a response of clearing backslash ..try this..

 

[billyharris72]

Just wanted to say thanks for the help on this - the problem is now solved. I managed to get Phd2 to calibrate using a large calibration step (about 3000ms), though it took ages. At least that removed any concerns about leads or hardware, and a bit more digging led me to investigate guiding speed. That's when I found that the guide speed was set to x0.1 sidereal. Bumped it up to x0.5 and it now works. Not especially well - I suspect it will take some tinkering to optimise the guiding - but it's working.

Thanks,

Billy.