Autoguiding help needed for guiding an f4 200mm Newton

[uhb1966]

Ok, so i want to guide my f4 200mm aperture Newton which is mounted on an EQ6.

I am heavily interested in getting the orion starshoot autoguider because its well priced and comes with drivers for both mac and windows. The guider is often sold with two corresponding guidescopes, one being a mini 50mmx162mm guidescope(also Orion) and an 80mmx400 larger guidescope.  In terms of pricing, the difference is minimal.

Which one would probably be better suited? I have no idea because i'm really new to AP

Thanks a lot in advance!

[red dwalf]

if i was you i`d try and get a qhy5 mono, these are the same as the orion guide cameras but alot cheaper, discontinued at the moment but many available on the second hand market.

guide scopes available that work well are a skywatcher st80 or for something alittle lighter a 10 x 60 altair astro finder guider, i`ve tried both with my 80mm triplet and both work very well although the st80 is bigger and more weight 

[Owmuchonomy]

+1 for the Altair Astro specifically due to the very relevant accessories it comes with.  I use a SLX Lodestar in mine.  Always plenty of stars to follow.

[ollypenrice]

The problem with guidescopes when used to guide reflectors is that the mirror in the reflector can move (this is called mirror flop but is rather a harsh term for a small movement.) Still, that movement is invisible to your guide scope and so you'll have a form of differential flexure. It is best to guide reflectors with off axis guiders because the OAG uses the same light cone as the imaging reflector. If the mirror moves the guide camera will respond to that movement.

But many people say they get away with it. I've always used an OAG when imaging with reflectors, though. Who knows what you would find?

I'd just go for a QHY5 as well and run it in PHD.

Olly