PHD2 comet tracking

[Lars Karlsson]

Hi,
I want to use PHD2 to track on comets with an off-axis guider. I can in the manual read that it's possibly and with help of CDC Cartes du Ciel I can get the needed tracking rate direct. But the manual don't tell how to connect CDC and PHD2 and transfer this needed data.

Here is what the manual says:

There are a three different ways to provide the comet tracking rate to PHD2.
 Some planetarium applications, like Cartes du Ciel, can send the rate directly to PHD2;
 You can enter the tracking rate manually, or,
 You can train the rate in PHD2 by following the comet for a period of time in the imaging camera.

It's the first point I want to do. Of course I can put in the data rate direct, but much more convinient if CDC can deliver it direct to PHD2. Maybe it's not implemented yet?

BR
Lars

[Patrick Chevalley]

Hi,

You need the last CDC beta version available from :
http://sourceforge.net/projects/skychart/files/0-beta/

Then the documentation is here:
http://www.ap-i.net/skychart/en/documentation/toolbox#phd_guiding

Patrick

[Duncan Evenden]

Hi Lars,

I haven't tried the PHD2 comet function or the CdC capability of passing rates but as soon as my pier is hardened off (poured yesterday :-) ) it will be one of the things on my list to try to see what works best for me, you never know when a comet is going to come to life and become a lovely imaging target so it's best to be prepared with a known good technique...

You don't say what mount you are using. If you are an EQASCOM/EQMOD user there is a function for setting custom tracking rates using MPCC (Minor Planet Centre) data. You can also get EQMOD to slew to the object/comet. This is a link to the EQMOD Comet YouTube video explaining what to do. EQMOD will display the calculated rates for each axis but I don't know if these are usable in PHD2, something to look at this afternoon maybe. I successfully imaged Lovejoy with no guiding using this method and basic (tripod mounted HEQ5) polar alignment. Also asteroids.

KR and clear skies

Duncan

[Lars Karlsson]

Hi Patrick and Duncan,
Perfect, I will test it to the weekend, as you say, must be prepared when the comets come. I have a EQ6 Synscan mount. Normalaly I use the NASA site http://ssd.jpl.nasa.gov/horizons.cgi?s_type=1#top  to calculate comet orbits and bandata. But with PHD2 it will be much more convinient.

Thansk a lot!

Take a look at my homepage: http://www.astrofriend.eu/ I have put some of my astronomy projects there.

/Lars

[Lars Karlsson]

Hi,
Now I have installed the new beta 3.11 version of CDC and also PHD" 2.5 dev2 versions. Just doing some test at home where I don't have the mount or guide camera.

I got CDC to sent rates to PHD2, fanatastic, it's a small revolution ! I don't have to do do this calculation manual any more.

Maybe I will find a comet bright enough this weekend to do some fieldtest on. I will give

C/2014 Q1 ( PanSTARRS ) a try. magn 11. Never done it before on a comet that dimish, maybe work if it's dark enough.


Later in november I aiming for comet Catalina.

Thanks a lot !

/Lars

[Lars Karlsson]

Hi,
Now I have done some test with indirect guidning on comets with PHD2 and CdC (Skychart). Not fully success yet but closing in.

I have some suggestions for PHD2 developers.

The little window down and left in PHD2, today the message "Guiding" comes when guiding, maybe when enable comet guidning also the text change to Guiding comet", as it now I'm not shure what PHD2 is doing.

Another very helpfull tool is some help where to place the guidning star in PHD2 window, when guiding on comets the guide star moves and you don't want it to come close to the borders. If PHD2 could draw an arrow with direction of guide stars and with the lenght according to speed, pixel per hour or something simular. It will be very helpfull.

Today it's not possiblie to enter rates manually in PHD2 comet window, it's just blank out directly, you have to use up and down arrows to set comet tracking rate, no decimals possiblie.

My tutorial for PHD2 comet tracking I'm working on:
http://astrofriend.eu/astronomy/tutorials/tutorial-comet-autoguiding/tutorial-comet-autoguiding.html

BR
Lars

[Lars Karlsson]

I added two more  images from another test I did later.

http://astrofriend.eu/astronomy/tutorials/tutorial-comet-autoguiding/tutorial-comet-autoguiding.html#part06

See bottom.

Maybe someone who understand the comunication between EQMOD and PHD2 can explain what's wrong?

EQMOD is set to: EQMOD SideOfPier set to "Pointing" as I was told to do with the new version. It has worked with older versions.

It's very hard for me to test this function (very few comet and asteriods in my limited view from balcony) and now is the summer comming. If it could be tested in the EQMOD simulater or alike it had been much easier. But can't see that's possiblie.

/Lars

[Andy Galasso]

Lars,

Thanks for the feedback.  I added an item to the phd2 issue tracker (#530) so we don't lose track of the suggestions.

Andy