PHD2 Calibration Failure, RA Star did not move enough

[Josh123SV]

Hello everyone
 
I am relatively new to the world of astrophotgraphy and autoguiding. My current setup is: Skywatcher 200pds, eq5 goto mount, canon 500d (unmodified), and my autoguiding system is a stock skywatcher 9x50 finderscope and a qhy5ii-m guide camera. 
 
I had just purchased an adapter to connect my finderscope to qhy camera and was eager to see if it all worked, on the first clear night. Everything seemed to be going smoothly with the odd hiccup but nothing that was unfixable. I had all the necessary ASCOM drivers and all the necessary equipment. Yet, for the love of me, I could not find a solution as to why PHD2 said 'RA calibration failed, star did not move enough'. After about 61 West Steps, this popup immediately appears. 
 
I have previously seen this question posed on Cloudy Nights forum at: https://www.cloudyni...not-move-enough. I have since used the PHD2 calculator, yet this did not resolve the issue. And I have uninstalled and reinstalled PHD2. Also, the guide star does appear to move a little bit. Additionally, I was pointing around 15 degrees and I could see plenty of stars in FOV.

 

I will attach a PHD2 log so you can see what the issue may be with this and how to troubleshoot this. 

 

Any response is greatly appreciated,

Josh

PHD2_GuideLog_2022-03-25_161817 21.18 pm.txt

Edited March 25, 2022 by Josh123SV

[Same old newbie alert]

First of all how are you guiding, if pulse guiding you should be calibrating on the equator Dec 0

The star didn't move enough because of backlash.. if you purposely nudge the mount with the hand controller until you physically see the star move the backlash is taken up... Not. Sure why you have that amount of backlash on the RA axis thou.. calibration is about measuring how far the star moves on a guide pulse so it can correct the star movement to keep it centered 

[almcl]

Is there a reason you are using GPINT as your mount type rather than  EQMOD ASCOM HEQ5/6 ?

 

[Same old newbie alert]

Hi Josh, you seem to lose the star quite frequently on your calibration, increase your search region as it's on 15 pixels... And the first 2 guide pulses west don't move, this is backlash so take up the slack before you calibrate..

[michael8554]

Some conflicting results in the GuideLog:

Your second of thirteen Cals was proceeding well and Completed, but lost the star at the first East return step:

 

Cal moved west past 25 on the display.

However by Cal number 10 the West Calibration became extremely erratic , with RA moving all over the place, in tiny steps.

Mostly clustered around only 5 on the scale:

 

 

And by Cal number 13 the Cal was now more linear but never got past 3 on the scale.

And so PHD2 gave up after 60 steps and posted the "Insufficient Movement" message:

 

 

"I had all the necessary ASCOM drivers"

I'm not familiar with the EQ GoTo mount, but perhaps it inly supports ST-4 Guiding ?

Guidecam focus was awful HFD = 6.14 px

You were Binning the guidecam, so the image scale was a bit extreme Pixel scale = 7.73 arc-sec/px, Binning = 2,

"I have uninstalled and reinstalled PHD2"

Uninstalling PHD2 looses all your Equipment Profiles and the Dark maps, which you will have to re-enter.

You only need to run the Installer again, which overwrites the prog, but keeps the settings.

But PHD2 isn't to blame here, the ST-4 connection seems to be very erratic, or you were altering something I'm not aware of.

Michael

 

[Peter Reader]

I've had this error when EQmod pulse guiding was set too low. Try 0.9

[malc-c]

You don't mention how the mount is connected to the computer or what application you are using to control it.  Are you using an EQDIR cable between the computer and the mount, or does your mount have the USB port option, or are you using the handset as a pass through, with a USB cable between the computer and handset and the handset connected to the handset port on the mount?

If you are using a computer with either EQMOD or GSServer to control the mount then there should be no inputs from the handset.  You need to make any corrections to get a target in the field of view using the on screen NSEW buttons.  If you have EQMOD installed and are using that as the "driver" then you need to set the pulse guiding  setting (assuming you are connecting the guide camera to the computer via USB and not using the ST4 option) in EQMOD to between x0.5 and x0.9.  In PHD2 select  EQMOD HEQ5/6 (ASCOM) for the mount in the dropdown options for mounts (you seem to have the right camera selected already).

The scope needs to be set up in the default home position - Point North with the weights down.  Once the mount has been powered up and the PC booted and all the connections selected in the various applications, chose a star that is currently due south and on the celestial equator in the planetarium software.  With the scope unparked, instruct the mount to slew from the planetarium software.  Once the slew is complete, use the NSEW onscreen buttons in EQMOD to centre the star in the main camera's field of view and then sync the target in the planetarium application (this is typically done by right clicking on the star in the planetarium software and selecting sync form the options)  This then allows EQMOD to workout the polar alignment error or any other offsets ).  Now perform a calibration run in PHD2, followed by a run of the Guiding Assistant to measure the backlash.  Hopefully after that PHD2 will start guiding.  Once complete then select the target you want to image via the planetarium application, again, making any alterations to frame the target via the onscreen NSEW buttons.  Then let PHD2 select the guide star and start guiding.  I normally wait a few minutes for it to settle down before doing an imaging run.

Hope that helps

[malc-c]

Also, looking at the guide log, the focal length stated is 200mm.  If  you are using the stock 9 x 50 SW finder as a guidescope its focal length of the SW 9 x 50 straight finder I believe is 184mm and you are binning 2 x 2.  giving 7.73 arc seconds per pixel.  Exposure is also short at 500ms - set this to at least 1s or 1.5s.  I also noticed the guide log gave a full resolution of 640 x 480 where as the spec for the QHY5LII mono gives a resolution of 1280 x 960 so the binning has effectively reduced that to 640 x 480.  Now I'm no PHD expert, but that may be a factor.

Maybe @vlaiv can decipher  the log a little more.  As I said, I'm not the expert in this field

[Swoop1]

On 02/04/2022 at 15:50, malc-c said:

You don't mention how the mount is connected to the computer or what application you are using to control it.  Are you using an EQDIR cable between the computer and the mount, or does your mount have the USB port option, or are you using the handset as a pass through, with a USB cable between the computer and handset and the handset connected to the handset port on the mount?

If you are using a computer with either EQMOD or GSServer to control the mount then there should be no inputs from the handset.  You need to make any corrections to get a target in the field of view using the on screen NSEW buttons.  If you have EQMOD installed and are using that as the "driver" then you need to set the pulse guiding  setting (assuming you are connecting the guide camera to the computer via USB and not using the ST4 option) in EQMOD to between x0.5 and x0.9.  In PHD2 select  EQMOD HEQ5/6 (ASCOM) for the mount in the dropdown options for mounts (you seem to have the right camera selected already).

The scope needs to be set up in the default home position - Point North with the weights down.  Once the mount has been powered up and the PC booted and all the connections selected in the various applications, chose a star that is currently due south and on the celestial equator in the planetarium software.  With the scope unparked, instruct the mount to slew from the planetarium software.  Once the slew is complete, use the NSEW onscreen buttons in EQMOD to centre the star in the main camera's field of view and then sync the target in the planetarium application (this is typically done by right clicking on the star in the planetarium software and selecting sync form the options)  This then allows EQMOD to workout the polar alignment error or any other offsets ).  Now perform a calibration run in PHD2, followed by a run of the Guiding Assistant to measure the backlash.  Hopefully after that PHD2 will start guiding.  Once complete then select the target you want to image via the planetarium application, again, making any alterations to frame the target via the onscreen NSEW buttons.  Then let PHD2 select the guide star and start guiding.  I normally wait a few minutes for it to settle down before doing an imaging run.

Hope that helps

Malcolm- I have just cut and pasted this into an e mail to myself as an aide memoir for my setting up.

Cheers!