[LewisM]

Some experienced astronomers may have missed it in the beginners section, so restating the question here:

OK, so how do seasoned Vixen drivers get around using standard 2" filters in a Vixen system? I m talking photographically, not visually (visually, you add the Vixen 60mm to 50.8mm adaptor with compression ring and use a regular diagonal).

ALL threads in the Vixen photo tube system will NOT accept a standard photo filter thread. It's driving me nuts trying to figure it out, as I want to image H-alpha and O-III. I succeeded in "friction fitting" an H-a (Baader brand) previously, but I cannot get the O-III to fit (Orion brand) up against the T-ringinside the stepper ring.

Darned Vixen and their odd thread size!

I just don't know how short of taping a filter to the front of the flip mirror tube and using the through-tube for photos (but causing more vignetting not being full diameter)