Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

Need some Help - PHD Not Guiding in DEC


Deneb

Recommended Posts

Hi

I had this problem last night with PHD while it was calibrating. After it clears the Dec Backlash then tries to calibrate N. After 40 steps it says " Guiding in DEC cannot be Performed, DEC Guiding turned off".

Unfortunatly can't show you the graph, but it was only showing the RA tracking.

Now the Celestron CGEM mount has no polar scope fitted, as you can do a 2 star alignment plus add unlimted calibration stars for your alignment, just like how you would with EQMOD, im wandering due to not polar aligning the mount through your polarscope like you would do with an EQ6 would that have anything to do with it ?

I have made sure the mount backlash settings are set to 0. Thinking it might be an issue regarding dec balance all that seems ok, made sure there's no cable lag problem. I have left the settings in PHD as default & set as Auto.

Any Ideas would be appreciated.

Nadeem.

Link to comment
Share on other sites

Hi Nadeem,

Hmm strange one. Could you supply some details such as:

- How you are connecting the PC to the mount (i.e. are you using ST4 or a serial link)

- Scope you are guiding through, in particular the focal length

- Camera you are using for the guiding

- In PHD what setting have you got for the calibration step size

- When PHD calibrated the RA axis, how many steps did it take?

I'm not familiar with how you interface a PC to a CGEM, but is there some way you can check that the mount is receiving movement commands OK in DEC? (i.e. to rule out a dodgy cable etc.)

Link to comment
Share on other sites

Hi Nadeem,

Hmm strange one. Could you supply some details such as:

- How you are connecting the PC to the mount (i.e. are you using ST4 or a serial link)

- Scope you are guiding through, in particular the focal length

- Camera you are using for the guiding

- In PHD what setting have you got for the calibration step size

- When PHD calibrated the RA axis, how many steps did it take?

I'm not familiar with how you interface a PC to a CGEM, but is there some way you can check that the mount is receiving movement commands OK in DEC? (i.e. to rule out a dodgy cable etc.)

Hi

I've got an ST4 connected from a QHY5 to the mount, guiding through a 60mm scope with a focal length of 480mm, which I never had a problem picking up stars to guide with. The calibration step size is 750ms. Sorry could not remember how many steps it took for the RA axis apart from the steps it took before it failed. Unfortunatly did not enable the data logging, I would think that could tell you the commands which are sent to the mount.

Nadeem.

Link to comment
Share on other sites

OK, with a focal length of 480mm you'll probably want to ramp up the calibration step size. Try something in the region of 2000 and aim for calibration to occur after around 15 steps.

Link to comment
Share on other sites

Dont mean to ask a stupid question to you... but is dec guiding actually turned on? maybe you slipped it off by accident..? I doubt it as you say its in auto.. but you never know

Does it actually move the star at all when it starts to calibrate in dec?

Link to comment
Share on other sites

Dont mean to ask a stupid question to you... but is dec guiding actually turned on? maybe you slipped it off by accident..? I doubt it as you say its in auto.. but you never know

Does it actually move the star at all when it starts to calibrate in dec?

its not a stupid question at all, when it fails, it turns off the Dec after clearing the DEC backlash.

Nadeem.

Link to comment
Share on other sites

Hi

Just want to say Thanks to r3i for helping me. It was too murky to do any imaging so I tried what you suggested about changing the Calibration Step size to 2000ms & what do you know - It Worked ! Now it's guiding properly, as you can see from the graph:

Capture-1.png

Cheers

Nadeem.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.