ST80 or finderscope for guiding ??

[Skipper Billy]

I have taken my imaging rig to bits for cleaning/maintenance/improvement whilst there is no real darkness.

Its a SW ED80 on an Orion Sirius (HEQ5) and a SXVF OSC or DSLR camera for imaging and I have a choice for guiding between an ST80 and a SW 9 x 50 finder-scope  - either would be used with a QHY5LII and PHD2

My immediate thought is that the finder-scope is a lot lighter but I am not pushing the mounts abilities with an ED80.

What would you suggest - what are the pros and cons??

The ST80 has worked well in the past and I have never tried the finder-scope despite having the adapter to fit the camera to it.

Any thoughts are most welcome.

[JamesF]

I think there's more opportunity to get a rigid fixing for the ST80 so you don't get flexing between the two OTAs.  The finderscope mounting isn't exactly solid, unless you're planning to mount it a different way.  I've used one successfully though.

James

[RikM]

I've used both and didn't see any difference with my set up. I stripped the ST80 out to use for solar imaging and haven't bothered to put to back. I have had 30min subs with a 250PX on a NEQ6 with the finder guider. Theory says the ST80 will be better but I didn't see it in practice. That's just me though... your mileage may vary.

[Tinker1947]

The ST-80 looks the business against  a Finder Guider, and on paper should be better, i like the Tube rings for adjusting so the ST-80  acts not only as a guide scope, but also a finder scope using the PHD window as a view screen, once the ST-80 is aligned to the main scope i just look at the PHD screen to centre objects in the Main Scope sensor......

Finder Guide not the same to look at....

[ollypenrice]

Probably both would be fine but personally (in old gimmer mode!) I'd go for the bolted-down ST80. I could list a few reasons for this which might or might not really apply but I can't really make much of a list in favour of the finder guider.

Olly