Autoguiding with modded EQ5 unforeseen problems

[pixueto]

Dear all,

I am having a kind of mixed bag experience with my autoguiding project. I am happy because I got my kit guiding flawlessly yesterday night but prior to that I run into a lot of trouble.

I am using a modded EQ5 with a SW200P. My finder & guidescope is a stellarvue F50 which tales eyepieces. The finder is in rings with screws. I use the finder with a 2X barlow and a Philips SPC 880 (unmodded) + PHD.

Whereas my SPC won't be able to pick faint stars for guiding, so far I have been able to point the stellarvue finder to a bright star no farther away than 4 degrees which is fine. My problem is that, once I move the finder, I really struggle to align it again with the main scope. Also, I find it very hard to direct the finder and secure it where I want to by using the rings.

I would be very interested on hearing from someone who have had to deal with the same issues. When I started this project I was more concerned about software, wiring and the ability of the EQ5 to produce guided images but that seems to be OK and i'm having the real problems from a 'mecanical' side which I did not expect.

I could really do with some help. I thought of different possible solutions. I thought of using my old generic SW finder to align it with the main scope so I can find targets whereas I can remove it from the clamp and put the stellarvue with the rings for the guiding. Would that work or will a loose alignment everytime I remove it and put it back to find another target?

Thank you very much for your help ans suggestions

[Shibby]

I don't think I have the same finder as you, but I know what you mean about realigning the finderguider. With such a small FOV, it's impossible to know where you're pointing so I normally end up realigning it during the daytime.

Having said that, I recently realised that nailing the focus has revealed far more stars to my SPC900, I'm pretty sure I was guiding on a mag 9 star last time I tried, so I don't have to move it around much any more.

[themos]

Why do you need a finder? If I am "lost", that is, I don't know where the imaging camera is pointing, I save an image as low-resolution JPEG and either send it to live.astrometry.net or run astrometry.net on my laptop. What that does is calculate the RA/DEC coordinates of the centre of the image, which I then use to find out how to frame the target.

[Shibby]

themos, I think he means he doesn't know where the findeguider is pointing after moving it up to 4 degrees and therefore has trouble re-aligning it with the main scope.

[Starflyer]

If you can stretch to it then a QHY5 should give you plenty of stars to pick from without adjusting the finder/guider. If not then read up on modifying your webcam, or get Andy at Astronomiser to mod it for you. The easiest solution to your problem is longer guide exposures

[Quatermass]

My solution is to use my finder guider with the webcam in it after I have used my other finder scope that came with my evostar ed80. I line up my camera and finder scope as normal on a bright star so everthing is lined up. After that I take the finder off and use my other finder scope with the webcam in it to find a star with. Mybe not ideal but it works better then using one finder guide scope. The other option would be a cheap finder scope as Stan did with his set up. Like you say the software is not an issue its the hardware that causes the problems.