Hello,
I have a Williams GT81 with 166.7mm back focus and a Baader Herschel Wedge that eats up 114mm of it. The Focuser takes 55.8mm by my measurement. So the imaging plane is ~5mm inside the clicklock The drawtube is wound all the way in and I have one lens that reaches focus.
I'm thinking of replacing the 47mm long, 2" Baader click lock with the T2 version. I have the T2 ring that correctly holds the ND 3.0 and Continuum filters. So * I think * I just need the T2 Clicklock to solve all my problems! - a shorter path, a clicklock and the T2 surface to stop the nose of my camera/eyepiece from hitting the filters.
I'd be grateful for your feedback