Log in

View Full Version here: : Anybody use a precision centering adapter?


vanwonky
07-08-2011, 11:49 PM
Despite the fact that I think my collimation issues described here (http://www.iceinspace.com.au/forum/showthread.php?t=78584) seem to be sorted as far as I can tell I am interested in this adaptor (http://www.telescope.com/Orion-2-to-125-Precision-Centering-Adapter/p/52072.uts) simply because it seems to make sense. Does anybody use one and if so what are your impressions as to whether it aids collimation by centering the collimater perfectly every time (not my words!) and making sure your eyepiece is also centered correctly in the light path every time eliminating the supposed difference in positioning the thumbscrews can introduce. Bloody hell that sounds like an ad for it!

bartman
08-08-2011, 12:58 AM
I'd be interested in any response too....
Thanks Dave
Cheers
Barman

multiweb
08-08-2011, 07:21 AM
I haven't tried those but I have used Hotech adapters. If you drill your existing focuser/extension tubes with two more grab screws so you have three in total spaced 120 degrees you'll always be square and centered provided your tubes are a reasonably tight fit. I've found this to be the easiest mod and most practical thing to use for repeatability. There are a lot of things you need to keep in mind to have your light path centered and adapters are only a part of it.

jjjnettie
08-08-2011, 10:15 PM
I use the Hutech adaptor too. I've found it to be an awesome piece of kit.
With my other metal nose pieces, I wrap a few rounds of plumbers tape around them to achieve a snug fit. It also dampens down any vibrations that the camera can cause when the shutter is released.

Archy
11-08-2011, 05:30 PM
I have: it works in centering a 1.25" eyepiece or collimator, but then the problem becomes: how do you know the 2" adaptor is centred.

vanwonky
12-08-2011, 11:11 AM
Yes good point! And now that has become patently obvious since my cheshire has arrived. When looking down it I can see one side of the focuser drawtube in view i.e the chesire is in no way aligned straight down the tube. Loosening the 2" adaptor thumbscrews I can adjust it to where it should be but of course that is not much use. So I imagine collimating is not really going to work in that state using it!

Raybot (Ray)
12-08-2011, 12:40 PM
Hmm, plumbers tape, is there anything it can't do ?

jjjnettie
12-08-2011, 12:46 PM
if plumbers tape doesn't work, then velcro or cable ties will. :)

asimov
12-08-2011, 01:04 PM
I have 6 screws in every adapter & focuser I own. This way I can tilt & center at the same time.

rider
12-08-2011, 03:01 PM
just a thought, which is obvious and probably taken for granted by all of you, but if you use the precision centering adapter for collimation, you will also need to use it for EVERY E.P. or camera you use during viewing sessions.
Otherwise any un-centered E.P. will not be directly on the collimation axis.