Astrofriend's homepage
Share: Twitter Reddit Facebook Gmail Gmail Email
Search Astrofriend's homepage:

Valid CSS!

All pages shall now have been validated

Info Cookies (Kakor) / GDPR


Advertisement / Annons:

Off axis auto guiding on comets


  1. My choice of equipment and software to do off axis guiding on comets
  2. Setup of PHD2 Beta
  3. Setup of CdC (Skychart) Betaversion
  4. Start comet guiding in PHD2
  5. Overview of Astroserver Screen
  6. Test on comet C/2014 W2 Pan-STARRS

1: My choice of equipment and software to do off axis guiding on comets

Latest update: 2016-01-21

Comets and asteroids are sometime fast moving objects relative to stars and then it's tricky to take sharp photos of them.

You can reprogram your motors in the mount to have speed adjusted for the comet, but then you are limited to the precision of your mount. You can also have a separate telescope and auto guide on the comet core and it works if you are lucky, sometime comet core are so diffuse that it's not possibly.

When I visited the observatory at La Palma 1997 I come in contact with the people that was collecting data of the comet Hale Bopp. They did something that I noticed, they follow a star with the guide camera and did some trick to follow the comet. I don't now any details more than that the guide camera was analog and with an intensifier. The guide camera was also free moveable relative the telescope's main camera by stepper motors.

Now 17 years later when I have my own goto mount (EQ6) I wanted to do something similar as an amateur astronomer and in Windows environment. By luck I found that the program I'm already use, PHD2 had a beta version that could do exactly that.

How it works? PHD2 guide on a star and let the software calculate how much the speed differ from the star and offset the guiding speed online. Then it's possibly to even have a off axis guider. The last is what I'm going to talk about here.

The hardware you need to do it the same way as I do it. I have a EQ6 Synscan controlled by EQMOD, but I believe most computer controlled goto mount will do. And you also need a guide camera, I have the QHY5 and it's connected to the main telescope through an off-axis adapter.

Here is a list of what software I use and where you can download them, all of them are free.

There are maybe other software that can do this too. Frank wrote to me and told me that his program MetaGuide can do this years ago: Bliss/MetaGuide/

I don't have any experience from that software, but would be interesting to do a test in future.

I assumes you are already familiar how to use a guide camera that is computer controlled before continue with this. And you must know how to setup PHD2 for auto guiding, otherwise it will be too complicated. See the PHD2 manual, PHD2 is under development so function will be added and changed from time to time.

In its simplest form you only need the guide camera and PHD2, but then you loose some functions.

Go Back to content

Go Back
To page II

Advertisement / Annons: