Something bugging me

[watersblue]

Most seem to recommend the ed80 on an heq5. What is used for a guidescope in such a setup?

Thanks.

[ronin]

Many pick the ST80.

Or an off axis guider.

[nmoushon]

There's 3 options really:

1- Convert the 50mm finder scope to a finder guider. I have does this and it works quite well even in my LP skies. I have achieved 5min subs easily. I'm sure I could get 10min if I spent a night fine tuning but havent tried that yet.

2- Attached a ST-80 to your ED80 either by scope rings or with a parallel bar

3- Use an OAG (Off Axis Guiding), which goes between your camera and the focuser. It takes about 2% or so of the light that comes through the tube and uses that to find stars to guide from.

4-This is not used as much as the others and is expensive but is an option - buy a CCD camera with a built it guide chip. I just bought a second CCD that does this and is actually on its way as we speak. So can't give personal advive on this one yet but looking forward to trying it out.

[lensman57]

Most seem to recommend the ed80 on an heq5. What is used for a guidescope in such a setup?

Thanks.

Hi,

The secret to good guiding is to minimise the factors that effect it adversely. Weight of the guiding set up and flexture of the tube and the mounting rig play a big part in this. ST 80 is poular but I think is overkill for a short FL ED like the ED 80, it also adds a lot of weight and bulk to a scope that although is optically good is not exactly a prime example of high build quality, I have one so I know what it is like. I think that you are better off with a 50~60 mm finder guider. A well set up 50 mm guider is good enough up to a 1000mm FL . If however , you were doing imaging with an SC or a long FL APO then you'd have to use something like ST80 for guiding.

A.G

[watersblue]

Okaay, thanks everyone. I didn't know about off axis guiding.