Autoguiding, please can you help?

[badboybubby]

Hello,

I'm still relatively new to Astronomy and would appreciate some advice. I realised during a recent spell trying to image M42 using my DSLR that I couldn't set my exposure length more than about 30 seconds before getting star trails so after some reading on these forums decided that I need to get an auto-guiding set up.

I have an unused 9 x 50 viewfinder that came with my 200EP sitting around so was contemplating doing the 9 x 50 Mod but need some advice. My 2 Scopes are Skywatcher 127 Mak for Planets and a Skywatcher 200P Newtonian Reflector for DSO's.

I currently own a SPC900 with IR filter (not Long Exposure modded) camera and wondered if its possible to try guiding with this? I do a lot of my Astronomy from my light polluted back garden and have heard that it might struggle picking up a guide star? If that's the case I would also consider buying a QHY5 currently £180 but wondered if its worth buying a better camera (up to £300) that could be used for both guiding when I attempting DSO imaging or as a high frame rate planetary camera better than my SPC900.

One final question. Is it PHD that sends the adjustment corrections to my mount (HEQ5 Pro) or does the camera have some specific hardware that does this?

Any help would truly be appreciated, I've searched a lot and not found all the answers I need.

Cheers

Scott

[Tim]

Welcome to the dark side

My honest advice would be, if you are serious about astronomy being a long term hobby, and you want to take long exposures, then start with investing in a decent guidecamera. It will take away so many frustrations and wasted nights, will be reliable and dependable.

As guidecameras go, you will not find better than a StarlightXpress Lodestar. I have used loads of different cameras for guiding and the Lodestar leaves them all standing. At the moment I am using very long focal length scopes, imaging at F10, and using a tiny pick off prism in an Off Axis Guider to find a guide star, and the Lodestar has never let me down, it just sees stars that other cameras wont.

If eventually you decide that autoguiding isn't for you, then the Lodestar has great resellability.

Some cameras do have the ability to send guide commands straight to the mount. Personally I find it more convenient to let PHD do the work, it is so easily adjustable and intuitive.

http://www.firstligh...autoguider.html

or a higher res version for more £££

http://www.firstligh...autoguider.html

Hope that helps

Tim

[ollypenrice]

I agree with Tim though the Lodestar has been replaced, I think. I hope they've improved the cable input because this is a weak spot for which Telescope Service do a fix.

You might also pick up an Atik 16ic. This is as sensitive as the Lodestar or possibly even a tad better, but it needs a power supply so one more cable in the spaghetti! They come up second hand but are no longer made.

I second Tim's points about having a good guide camera. Guiding problems are consistently the greatest impediment to a night's work. I wouldn't go near standalones, myself. Ian King encouraged me not to compromise so I went for the Atik, though I have a Lodestar now as well. It was good advice, as ever from Ian.

And, yes, welcome to the dark arts...

Olly

[ThomasBR]

I use a QHY5 as guide cam and either a modded 9x50 finder or an ST-80 as guidescope on a HEQ5 (and a 200p telescope). I normally guide using PHD guiding in the pulse guiding mode so the signals are send via EQMOD to the mount. The QHY5 is also able to do guiding via an ST-4 port on the cam and HEQ5 (via PHD or similar).

I am not a pro imager like Tim and Olly but this setup gives decent results for my skill level (read: novice). I should be noted that I have not made the QHY5 work with my recently acquired OAG so the may be on to something. For the moment I am awaiting an extension tune (and clear skies) and the I hope to find some guidestars with the OAG/QHY5.

Kind regards

Thomas

[ArmyAirForce]

I just bought the SX Lodestar a few days ago, but have only used it once so far. I have the Explorer 200 PDS scope and the ultra thin TS Off Axis Guider. TS recommended the SX Lodestar due to its sensitivity and the small prism in the OAG. I was very impressed with my first go using PHD software to run the camera. It was even following the guidestar when cloud was obscuring the target! Obviously not solid thick cloud, but thick enough to stop me seeing Orion with the naked eye. Now obviously you can't image through cloud, but it does give an idea of the sensetivity of the camera.

It is expensive compared to some other options, but worth every penny in my opinion, especially in a light polluted area where star contrast with the background sky is reduced.

I also made this cable support to take the load off the plugs/sockets.