Hi all,
I recently purchased a ZWO filter wheel for RGB planetary imaging. I was always worried that I might not be able to reach focus with my current imaging set up which is ASI120MM + Televue x2.5 Powermate + filter wheel on a Sky Watcher 10" reflector.
Well, as I thought, I couldn't reach focus at first. I needed another inch of inward focus. So after scratching my head for a couple of hours and surf the web for solutions (such as moving the primary up the OTA), it dawn on me that if I got rid of the 1.25 eyepiece adaptor on the focuser, I actually gained about an inch. All I had to to was to unscrew the filter wheel nozzle and connect the filter wheel straight onto the focuser tube adaptor (see pictures).
It all connected well and I was able to reach focus with the filter wheel on, with a centimetre to spare.
End of story? Not quite.
Has it happens, the focuser adapter's threaded section onto which I screwed the wheel (sorry for my appalling lack of technical knowledge
) is too wide (it's the section next to my fingers on picture 3). When I screw it nice and tight, the threaded part goes too far into the filter wheel casing and pushes against the filters, preventing them from rotating normally. To put it simply, although it connects well, the threaded part is too wide. In order for the filters to rotate freely, I have to not screw the adaptor tightly, but then there is some play between the focuser and the filter wheel, making the imaging train unstable.
Do you know the exact name what I call the fosuser adaptor? Could I find one with a narrower threader section?
Thanks in advance for your help.
Eric
