Here is my modified 2" to 1.25" adapter. Back story is that I had replaced my stock focuser with a Feathertouch when I was binoviewing because the stock focuser was not really sufficient for the weight load and I needed the lower profile.
I have kind of lost interest in planetary observing these days (the only think I kept the Binotron for) so I decided to sell the binoviewer and focuser and convert my dob back to the factory focuser.
Now the concern was that the stock focuser was just enough taller that I would not be able to reach focus, but as it turned out, I could, but it was close. What bothered me though was a problem that I had with the focuser adpapter itself, which was that my device would not fully seat in it due to interference from the gain knob and battery cover. I took this opportunity to mod up the 2" adapter so the device would sit flush at the flange to the top of the adapter.
I just used a grinding wheel to hog out the unwanted material and kind of smooted it with a hand file.
Crude, but now my device sits flush to the top of the adapter.
For someone that is only a few millimeters short of focus, going to a nose with no ridge at the top and modding the 2" to 1.25 adapter might do the trick. The Scopestuff C mount might too, but I think it has the same issue with the gain control knob.
This 1.25" nose has a flange which takes up some back focus:
This one does not have the flange, but now your problem is that the gain knob and battery cover can hit the top of the adapter:
And here is the modified 2" to 1.25". This one has M48 thread, so you can mount either 2" or 1.25 filters, and is a lot cheaper than the Scopestuff unit. though the Scopestuff one gets you a bit more in-travel.
And here shows the clearance of the gain knob. I can roll the knob with the curve of my finger.
I make no excuses for my crude workmanship other than I have come to value function far more than form. I used to think that how something looked was somehow relevant to how it would satisfy me, but now I don't care and what matters is that it works. Some of my NV configurations are but bass ugly and weird looking to others, but I spend little time looking at my stuff and far more time than ever before looking through it.. LOL.
Edited by Eddgie, 06 November 2017 - 10:05 AM.