[Fr00t (Gary)]

Hi All, I'm relatively new to astro imaging.

I've got a Skywatcher 200 PDS with a 9 x 50mm finder scope.
It's on an EQ5 mount which I have motorised using stepper motors and a 3d printer board using AstroEQ plans. I've only used it standalone, and am looking to try some guidance with something like PHD2.

Can I convert the finderscope to a guide scope by adding a helical focusser and an astro camera?

I have a SVBONY SV305 with which I've got some nice planetary and moon images, but stars seem very dim with it, as I need about 2 seconds per frame exposures to be able to see the stars, and don't see any stars with the live view type 30fps. So I'm guessing the SV305 isn't suitable for the purpose unless I'm missing something in the settings to make stars more visible.

If a SV305 isn't suitable as a guide camera, would something like a ZWO ASI 120mm mini be able to work with my 9x50 finder scope?