PHD 2

[Astro Grandad]

Hi, I am trying to use PHD 2 on my Skywatcher eq35 pro mount, I do a precise polar alignment with my QHY polarscope carry out a 2 or 3 star alignment which requires very little manual adjustment, then I connect PHD 2 ( I have entered the parameters in PHD 2 for the guide scope) it finds a suitable star starts to guide for a couple of minutes then goes completely to pot, I have tried changing some settings on the main screen but nothing changes, its very frustrating as when you watch someone on a video using PHD they just click start and away it goes guiding for hours.

Thanks for listening

[Freddie]

How is your calibration? You make no mention of that.

[almcl]

After it has calibrated (and if you set up and take down your equipment each night you have to do this every time) run the guiding assistant.  This will give some suggestions and, at least to start with, it's worth accepting these. 

Randomly changing settings is advised against by the current developers (https://groups.google.com/forum/#!forum/open-phd-guiding) as it often makes things worse.

[Astro Grandad]

Hi Freddie sorry I know what you mean now, when PHD is calibrating sometimes it comes up with random messages sorry can't remember what they are but it's something to do with the steps or not enough movement now, bearing in mind this mount has been modified by dark skies (hypertuned) I thought all would be fine, it's probably me that's at fault

[Astro Grandad]

Hi proto star will try that one, I take it the guiding assistant is on PHD 2, sorry to appear dumb I'm new to all this and as my screen name suggest I'm no you Einstein 

[almcl]

The Guiding Assistant is on the Tools Menu. It needs to run for 2 minutes (more is better, but it can be stopped after 2 mins):

 

To force the mount to calibrate, hold down the shift key while clicking the guiding icon:

[Freddie]

4 hours ago, Astro Grandad said:

Hi Freddie sorry I know what you mean now, when PHD is calibrating sometimes it comes up with random messages sorry can't remember what they are but it's something to do with the steps or not enough movement now, bearing in mind this mount has been modified by dark skies (hypertuned) I thought all would be fine, it's probably me that's at fault

Does the mount actually complete the calibration or does it fail and give these messages? Obviously if it does not successfully calibrate, it won’t guide.

[Astro Grandad]

Thanks mate will give this a go weather permitting, will post results.

[Astro Grandad]

Hi everyone that gave me advice on PHD2, I have tried what was suggested and know I am getting some sort of guiding can get 3 minutes at a push, when I set up for a new session do the polar align with the qhy polarscope and star alignment all is well, then I do a fresh PHD2 calibration it keeps telling me there is no or little south steps so guiding will be poor, I have changed settings re-set settings but it still comes up about the south steps, do I need any other drivers like ascom !.

Many thanks

[michael8554]

The message usually indicates you have a lot of Dec Backlash - the Dec gears aren't meshing tightly enough.

Before you Calibrate move the mount North with the handset on lowest slew speed, until you see the guidestar move.

Then the Backlash has been taken up, and PHD2 Calibration pulses will actually be able to move the mount north in Dec.

To start a new Calibration instead of guiding with the previous Cal, which PHD2 will have remembered, press Shift Click and the Guide button.

After Calibration ends ignore the error message for the moment, and run the Guide Assistant as already suggested.

This will run a Backlash Test when you hit stop after a few minutes, if your backlash isn't too bad then the Assistant will recommend a Backlash setting that you then accept.

Michael

[Astro Grandad]

Thanks Michael will try that, its all a little confusing but is getting easier with peoples help

many thanks

[Freddie]

....and if it has lots of backlash (which it sounds like it does) get back to Dark Skies and ask them why given that they have supposedly tuned it.

[Photosbykev]

You don't mention it but if you are using Eqmod as well as Phd2 then the Eqmod default Ra and Dec guide speed settings are way too low at x0.1 The PHD2 recommended value for both is X0.9. If they are at x0.1 then the calibration routine won't be moving enough to complete the routine

Kev

Edited October 29, 2019 by Photosbykev

[Astro Grandad]

Hi there no I'm not using eq mod just PHD2 and a Altair ARO130 mono on a Skywatcher Evoguide 50 mm, main scope is a Skywatcher ED80 pro and the mount is a EQ35 pro hypertuned by dark frame. I carry out a polar alignment with polemaster which is very accurate and now I double check it with sharp cap pro, do the star alignment then set up set up calibration in PHD start guiding (not very well but ok) for a couple of minutes then it all goes wrong it mentions in calibration about the south steps not being enough so guiding will be impaired, I have tried suggestions from other members which has improved the guiding, I have also run the guide assistant which found a couple of areas of improvement but even when I implement these it still only runs for a couple of minutes then goes off the rails, wish l could show you a screen shot it looks like one of my 2year old grandsons drawings. Thanks for your input