Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

Phd And Meridian Flip


alcol620

Recommended Posts

I'm using APT software connecting to PHD to guide the scope.

Two questions:

1.     Always avoided meridian flips when imaging as it was difficult to understand what would happen to the image.

However, took the plunge last night and it raised the following issue. 

Imaged the Rosette Nebula until it passed through the meridian. Used APT plate solving to solve the Rosette Nebula and it duly solved and centered the image (upside down compared to the image the other side of the meridian). However, when I set PHD guiding again it failed to do so and one of the axis ran off the screen. Presumably I don't need to re calibrate PHD having carried out a meridian flip and commenced imaging the same image? Which setting in PHD needs to be set in PHD to recognise the meridian flip?

2.  Having set up the camera imaging plan and PHD to guide. Is there a setting in PHD that allows it to ignore spells of cloud that causes it to lose the target and stop guiding. I assume there is one, as many have said they set up their rig and go to sleep! If PHD stopped guiding once a cloud caused it to lose a star and not start guiding again once the sky cleared, no further guided images could be taken and we know what that means.

Thanks for looking

Alec

Link to comment
Share on other sites

Hello,

after the meridian flip, which axis ran of the screen? If it was the DEC axis, then maybe you had the setting "Guide North only" or "Guide South only" before.

I think most people recommend a recalibration after the meridian flip although i don`t do it myself. The only thing i do is change the position of the counterweights to be east side heavy again.

As for the second question: If PHD loses the sight of a star, it should start the guiding process again when the star is visible again ( this is how it works with me and i have standard settings).

I´m not sure if it will still work when the cloud persisted a long time and the star has drifted alot on the guider sensor.

best regards

Matthias

Link to comment
Share on other sites

It is possible to flip and not have to recalibrate PHD.  I am able to do this (but more through luck than good judgement).  Firstly, are you pulse guiding or using the ST4?  (I think you need to pulse guide if you want to avoid re-calibration).  Secondly, there are a whole load of settings in your software that say things like "Reverse ... after meridian flip", that you might want to take a look at.  I use SGP and have a different mount, but I am sure that someone who has your gear will be along soon enough to tell you how to do it.

Link to comment
Share on other sites

Thanks Guys

I will look into this further following your comments. My understanding is that I am pulse guiding. My laptop is connected to the mount via the HitecAstro EQDIR adpter.

PHD does start guiding again after losing a star, but if this is a period of time, then it does not seem to start again. I will check the Guide N/S setting

Link to comment
Share on other sites

Thanks Guys

I will look into this further following your comments. My understanding is that I am pulse guiding. My laptop is connected to the mount via the HitecAstro EQDIR adpter.

PHD does start guiding again after losing a star, but if this is a period of time, then it does not seem to start again. I will check the Guide N/S setting

Guide North South setting are on Auto

Link to comment
Share on other sites

Hi Matthias

During the cloudy spell tonight played around with PHD. Made sure my PHD Dark library was up to date. Pressed the "Auto-select star" option after guiding started and watch PHD recover from lost stars over 10 minutes or more. Even covered the guidescope and left PHD running while it pinged at me and flashed red on the screen. On uncovering the guide scope PHD recovered the position and continued to guide.

My question is answered.

Thanks

Alec

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.