TheSkySearchers

• 1. Increase the guide speed in the mount to 0.9x sidereal. This can help to mitigate the Dec backlash problem in the mount and will let you use shorter exposure times.

• 2. Try binning the guide camera at 2x2. To do this, create a new profile with 2x2 binning and the new guide speed you set in step 1.

• 3. Disable star-mass detection for now – that’s on the Guiding tab of the Advanced Dialog

• 4. When it’s time to do a calibration, *always* move the mount north as the last step before starting the calibration. You can do that with a slew or by using the hand-controller. Just be sure you can see the stars moving on the display.

• 5. Try to use guide cam exposures of 1-2 seconds with this setup. Longer exposures give the mount too much time to wander off track, which can affect both guiding and calibration.

• 6. Re-run the Guiding Assistant with the new set-up and accept its recommendations. Re-run the backlash test and look at the graph to see how the mount behaved.- you can do this even if something went wrong with the test. For that matter, you can use the ‘Review Previous’ button in the GA to see what happened in earlier tests.

• 7. Don’t monkey around with the guide parameter settings, that’s just making things worse. You need to develop a clear view of what your mount is capable of doing before trying to figure out how best to work around its problems. The Guiding Assistant runs will do that for you – you should expect a lot of uncorrected periodic error in RA and a lot of Dec backlash. If the Dec backlash is too large for PHD2 to handle with Dec backlash compensation, you can guide in only one Dec direction. There are instructions in the Help guide for that and it can work very well for you – lots of people do it.

Hope this info helps make your autoguiding just a little (or maybe even a lot) better.

Cheers,
JT

yobbo89 wrote: ↑Sat Aug 24, 2019 2:07 pm I have one tip that may or may not help people guiding with an asi zwo camera, give ascom driver a go instead of the native zwo driver , and use 8 bit instead of 16 bit.

this will help avoid those driver crashes or long hangs

UlteriorModem wrote: ↑Sun Aug 25, 2019 2:18 am Good pointers!

Only thing I have to add is to make sure the mount is pretty well polar aligned before you start any of this.

Otherwise you will end up chasing your tail

XCalRocketMan wrote: ↑Sun Aug 25, 2019 12:13 am

yobbo89 wrote: ↑Sat Aug 24, 2019 2:07 pm I have one tip that may or may not help people guiding with an asi zwo camera, give ascom driver a go instead of the native zwo driver , and use 8 bit instead of 16 bit.

this will help avoid those driver crashes or long hangs

And keep in mind that the older ASI cameras (ASI120mm, mc) do not work well with hubs or extended USB cables. ASCOM is a better choice. I've since replaced my ASI120mc with a QHY5L-II so that I can go back to using the built-in hub in my ASI1600mm camera.

• When in doubt, Create a NEW "Equipment Profile" and fill it out accurately.
  Then run the Guiding Assistant, and follow its suggested settings.

Mike_Lewis wrote: ↑Sun Nov 17, 2019 4:16 pm I attended a lecture on PHD2 Best Practices this weekend. The speakers were none other than Andy Galasso and Bruce Waddington, so I take the information imparted as gospel. Most of what they explained was information I have been long been aware of, but one thing surprised me; PHD2 works best with imperfect polar alignment. They suggest that PA should be off by 5 to 10 arc minutes. The reasoning is that such misalignment keeps the guiding pulses coming and the error becomes "predictable" to the software and keeps the drive gears engaged resulting in more stable guiding.

I immediately thought about all of the hours I've spent in my life (before I bought PoleMaster) working at getting my PA error under 1 arc minute, my old standard. Completely unnecessary. I do wonder if that error is appropriate if guiding a scope at f/10 or so, but didn't find a chance to ask.