2" Filter Wheel with visual back / for visual use
Posted 04 April 2011 - 06:59 PM
I would like to equip my scope with 2" filter wheel for use with 2" UWA EP's.
Ideally, this would be same mechanism as with 1.25" wheels where front / scope side has a tube which goes into diagonal (male) and back / EP side has a tube into which EP is inserted (female), also called visual back.
Unfortunately something like this does not seem to exist at all for 2" filters. I purchased a used Orion 2" filter wheel just to find out that it lacks visual back or as orion states: "not intended for visual use"
Is there a way to add a female visual back to orion 2" wheel or is there a 2" wheel which comes with a visual back?
Posted 04 April 2011 - 07:28 PM
Check for T2 eyepiece holders.
Posted 04 April 2011 - 07:37 PM
For use with all of the Baader Astro T-2 components, the T2-28a Expanding Ring is used to convert the 2" threading of the 2" Clicklock Holder (CLSC-2) or T2-17 holder into internal T-2 threads. It's ultra-low profile takes up only 1mm of length.
- ausastronomer likes this
Posted 04 April 2011 - 07:54 PM
I installed a Moonlite (low profile) focuser as well to give me enough in-focus on my 8" f6. The filter wheel needs a fair bit of extra travel, so you have to be sure your scope has the right amount to accomodate the extra length.
Posted 11 April 2011 - 07:56 AM
Thanks for advises, that is exactly what I needed.
But, as dyslexic has mentioned I will most probably hit a focus issue We will see, part is ordered.
Posted 11 April 2011 - 11:57 AM
You can either use the whole barlow or, depending on the barlow, you can just thread the front lens element into the filter wheel. On the Orion 2" filter wheel, the nosepiece (on the telescope-side) screws into the main filter wheel piece using standard M48 filter threads. This is also the threading used in the lens element of the 2" GSO 2x ED barlow (other barlows may use it as well, but I know the GSO oes for sure). This means that you can screw the barlow lens element directly into the filter wheel in place of the nosepiece. This reduces the distance between the lens element and the eyepiece that you insert into the ep holder you just ordered, which keeps the magnification increase more reasonable.
There is some discussion of this here.
Posted 14 June 2011 - 08:51 PM
Posted 14 June 2011 - 11:48 PM
Posted 15 June 2011 - 12:43 AM
The setup above only has a 38mm clear aperture (due to T2 components) but I have adapters on the way from Germany which should allow me to connect the wheel to a GSO diagonal giving 46mm CA.
Posted 15 June 2011 - 06:50 AM
I am really looking forward to the next Mars opposition when I can do some quick A-B-C filter comparisons.
Posted 15 June 2011 - 11:24 PM
What do you do with the dual filter wheels?
Posted 16 June 2011 - 06:54 AM
Posted 16 June 2011 - 08:11 AM
To reach focus I have had to saw off 3 cm from the lower edge of the upper cage. (the video is previous to cutting the edge). Also I have turn the upper cage at the shame position that the focuser is in LB12" and 10". In the LB 16" it is just above the fulcrum (pivot), so the focuser tube is Always horizontal and for low elevation objects I had to sit very low.
The body of Baader steeltrack focuser can be put instead of the original focuser in the origigal base plat. A couple of headless allen screws keep the fosuser in place. This is a lower profile focuser than the original.
The filter wheel is for four 2" filters. I will use NPB, OIII, H beta and an empty space for unfiltering vision. In the nosepiece I can put the 2" variable Polarizer or neutral filters I have. The filter wheel comes with 2" (M48mm) filter screw plus T T adapters. For the eyepiece holder I order a Baader click-lock 2" clamp (model for C8-C9.25 + SCT srew-T screw adapter). Temporally, I am using a SCT Meade visualback +SCT srew-T screw adapter.
I want to share this filter wheel with my C11, in which I use also Click-lock clamps (visual back + diagonal)
Posted 17 June 2011 - 11:12 PM
some more details here: http://www.iceinspac...ead.php?t=76917
I use a nosepiece on the front of the filter wheel since I have a feathertouch crayford focuser on the C11. There are all sorts of adapters from Baader and Telescope Service (in Germany) but the SCT adapter sold by WO for their diagonal would let you connect the filter wheel directly to your 9.25; note that the M48 threads are not a perfect match between the WO gear and the Orion filter wheel but they are secure enough IMO.
The clear aperture of the WO diagonal/filter wheel setup is 38mm but I think that's the same as the C9.25 so no problem there. I intend to mate the wheel with a GSO diagonal giving 46mm clear aperture since I want to use it with a 41mm Panoptic.
The Eathwin setup also looks like a good option though you can only mount 2 filters rather than three in the filter wheel (in addition to one left empty) and you have to pay extra to get the dielectric mirror. I think the Earthwin is 40mm clear aperture which is not a problem for you but is a restriction in the C11 when using an eyepiece with a 46mm field stop.
Hope that helps and feel free to ask any more questions.
- AZ_J3 likes this
Posted 18 June 2011 - 10:10 PM
I would like to connect the filter wheel directly to the back of my C11 and then have a 2" nose piece sticking out for me to insert my regular diagonal. Is that possible or not? There is no way I can turn the filter wheel all the way around because of the feather touch focuser that sticks out a lot, but I need to be able to rotate the diagonal easily.
Posted 19 June 2011 - 12:37 AM
I would like to connect the filter wheel directly to the back of my C11 and then have a 2" nose piece sticking out for me to insert my regular diagonal.
In order to preserve clear aperture the best way I can see to connect the wheel to the C11 rear cell is to use the Astro-Physics part# ADASCTLC which adapts from the 3.25" rear cell to 2" accessories.
From there you could connect a Baader clicklock eyepiece holder to the M48 threads in the filter wheel body using the apropriate adapter - I'm not sure which adapter but I'll be able to tell you next week if you're interested as I have some new parts arriving (including clicklock eyepiece holder).
If you only needed the 38mm CA of the T2 threads there are simpler options.
Posted 19 June 2011 - 12:45 AM
The main concern I have is that there is no room to tighten the filterwheel onto the scope due to that big feather touch focuser, it sticks out like 3 inches.
Posted 19 June 2011 - 02:25 AM
Posted 19 June 2011 - 03:10 AM
An then, I use two different things, one for binocular and the other for monocular:
1.- Binocular observation: TV binoviever with a 5x1,25" filter whell. The filter wheel with a 2"-T2 nosepiece in one extreme and the T2-T2 adapter that comes with the wheel in the other. The binoviewver is atach directly to the wheel
2.- Monocular observation with 2" eyepieces: a Brightstar 4x2" Filter wheel (the same by Orion and Atik). With a 2" nosepiece (that comes with the wheel) in the telescope side and for the eyepiece side a Badder 2" click lock eyepiece holder. Note that this filterwhell uses M48 (the same pass than the 2" filter), the Click lock is the one designed for C8 and an adaptor M48 (=2" filter screw)-T2 is need. This filter wheel (as it is mounted, with 2" nosepiece and click lock eyepiece holder) is used also in my LB16""
Posted 19 June 2011 - 04:27 AM
Posted 19 June 2011 - 08:24 PM
The people at Orion are going to have to start giving us commission if this catches on Fred, and you'll get double
What do you do with the dual filter wheels?
I could certainly use the money!!! Anyway, I posted the pic just as an illustration of what can be done. In other words, load up both wheels with all of your favorite planetary and deep sky filters. In my case, if you look closely at the picture, you'll see that one of them is a Siebert Optics power mag wheel. Harry Siebert modifies an Orion Wheel by putting his own barlows and a focal reducer in. So, I'm really not THAT crazy. But the possibilities are there for mating 2 filter wheels, presumably with some vignetting due to the stacking.
Posted 20 June 2011 - 07:16 PM
The parts used in the pics are: BA2956220 clicklock eyepiece holder, BA1508020 external SCT threaded ring, TSROTSC-M48 SC to M48 360 degree rotating ring(2 parts, the outer part holding a dovetailed ring) and the filter wheel. The parts were purchased from Telescope Service in Germany and the clear aperture is 44mm.