Today I secured a little Zenithstar 66 for double duty guiding / wide field imaging... I was just wondering what I need to buy in order to use my QHY8 with it.. I've read that an SCT to 2" adapter is what I need, but cant seem to find exactly what item this is...
Here is my auto guiding configuration using the original Orion Deep Sky Star Shooter on the WO 66 Petzval that I purchased from Ron at Sirius Optics.
You need to be careful with these WO 66 Petzval’s – they require a 2” SCT fit diagonal for visual use although as you can see from the attached file, for auto guiding with the Orion DSSS, I use a WO 1 Ľ inch mirror diagonal and the focuser is racked out at around 3 cms, in its total of 6 cms travel.
My 2” WO Mirror Diagonal has a dual interface eyepiece adapter that I can swap out, from an SCT screw fit to a 2” push fit.
Just be carefull if you get the Bintel SCT Adapter, I think you will find that all these generic Adapters DO NOT have a stop at the end of the thread and will screw completely off the end of the barrel. The WO brand 2"/SCT Adapter has a stop at the end of the SCT thread to lock it against the barrel of the 66SD.
I guess that the end of the generic SCT to 2” adapters hits the rear of the SCT mirror cell before they reach the end of their internal thread, whereas the WO model has the inner stop designed for the WO focusers.