Basic Guiding setup

[Stub Mandrel]

I have a small budget scope, 50x350mm which has coated optics and looking through it at terrestrial objects appears to be quite a good objective and probably an achromat as I can't see any obvious CA.

I was thinking of using it as a finder, but gave up when I realised it doesn't give the FOV I need, but is it likely to work as a guide scope with PHD/PHD2 and a Microsoft HD Lifecam? It has the advantage of being much lighter than my economy 70x7600 achromat.

As for mounting it, I realise it has to be very rigidly mounted to the main scope, but how much movement am I likely to need to be sure of getting a decent guide star in frame?

[MarsG76]

Sounds like a plan, and you don't need much movement since your guide star should be as close to the object imaged as possible... of-course unless your PA is spot on, since the further from the object the guide star is the more radial blur you will start to see on your exposures.

[kalasinman]

An AOG is cheaper, lighter and more ridgid. You'll get plenty of guidestars witrh a modern sensitive purpose built guide cam such as the QHY5L-II mono

[Zakalwe]

An AOG is cheaper, lighter and more ridgid. You'll get plenty of guidestars witrh a modern sensitive purpose built guide cam such as the QHY5L-II mono

OAGs are a bit of a pain in the bum with a CCD. Using one with a DSLR will be a real pain due to the spacings. 

@the OP, nothing to be lost by trying it.

[Stub Mandrel]

 Thanks for the feedback

An AOG is cheaper, lighter and more ridgid. You'll get plenty of guidestars witrh a modern sensitive purpose built guide cam such as the QHY5L-II mono

I can see the advantages, but nothing is cheaper than kit you have already got :-)

Does sound like it's worth a go, though.

[Zakalwe]

 Thanks for the feedback

I can see the advantages, but nothing is cheaper than kit you have already got :-)

Does sound like it's worth a go, though.

It'll be an exercise in frustration. Your scope is f8, focal length of 1200mm. Sticking an OAG on that will give a very narrow FoV. Then adding a not-very-sensitive webcam will leave you struggling to get a guide star.  I could barely get guisdestars when using a f5.5 refractor, an OAG and a QHY5. I had to buy a QHY5L-II to make it usable.

I'd try the spotting scope first, or convert your finder into a finderguider.

Having said all of that, what mount are you using?  You have an EQ3 listed in your sig...you'll need something better than that.

[Stub Mandrel]

By "Does sound like it's worth a go, though" I meant the finder scope :-)

The mount is EQ3 but the tripod is EQ5, I get passable results up to 30 seconds, If I can extend that to a few minutes with guiding I'll be happy its a step upwards. An EQ5/6 is is the distant future.

I'm going to try using the Bresser for AP, and I have a good selection of camera lenses for larger targets.