I feel the light shroud is a must have accessory for this design. Not sure where you can buy one for the 12" SW though.
This may help: http://www.scopeshrouds.com/
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Posted 01 November 2013 - 10:04 AM
Posted 03 November 2013 - 09:02 AM
Great review. Still very useful info in 2013. Any recommendations for replacement focuser? Where can one get a shroud? Thanks!
Posted 18 June 2014 - 01:41 PM
Posted 29 June 2014 - 08:15 AM
Posted 01 July 2016 - 11:52 PM
Phillip, even though your review is years old, it is still benefitting newbies like myself just venturing into astronomy from the binocular stage.
I loved yor yor article about your journey to using the 12 inch dobsonian. OK so you have had years of use with the twelve inch Dob. What else has been learned or new that you can share about using this instrument?
I loved reading your previous write up that was clear, interesting, transparent, and honest I portraying your adventure to using the 12 inch.
I have not bought one yet so here are some questions:
1) What eyepieces do you recommend besides a 2x barlow?
2) How have you transported the Dob that weighs almost 100 lbs.?
3) Did you buy a coma corrector for this scope?
4) What other add-ones are beneficial? Equipment?
5)) I noted your 120 mm refractor. Do you do astrophotography with that?
I am looking at the Go To Collapsible model.
Thanks again for the article! You are a good writer.
Posted 11 July 2016 - 01:07 PM
Thanks for the kind words on the review.
In short, I sold the scope last summer to a fellow astronomy club member. I had just gone through a divorce and sold it more for budgetary relief, as I had just moved into a new house and was getting a bit paranoid about unanticipated expenses that kept cropping up like a game of whack-a-mole. When my finances stabilized, by the grace of God, I ended up re-purchasing the 12-1/2" scope Andrew Winzer built that's described in the beginning of the article.
The 12" SW Collapsible Dob is one I recommended back then, and after years of use I stand by that recommendation. Easily the closest you'd come to a commercial "grab n' go" 12"-dob. Broken down into two pieces weighing about 40-lbs. apiece, it'll fit into any vehicle I'd care to own. The entire time I had the scope, I transported it in a PT Cruiser and later a Kia Rondo. Set up in the field, including collimation, was typically 5 minutes or less.
One thing I immediately swapped out was the mirror-reversed right-angle finder for a straight-through, upside-down finderscope. That helped immensely. The finderscope shoe attached to the scope is a standard base that'll work with Orion finderscope brackets and the like.
I later on flocked opposite the focuser to bolster the contrast when looking at planets and their moons or near bright stars. I used Protostar Flockboard, with a plastic ABS backing and a top surface that was as black as, well, black velvet.
At f/4.9, collimation is important. Learn how to do it. As many online resources as there are for collimation, NOTHING beats watching someone do it. There are few better examples of something that seems like some mystical dark art when described but is very intuitive and straightforward once you actually do it. Get a decent laser collimator and a cheshire eyepiece; you'll be glad you did.
As far as eyepieces, it's got a 2"-focuser, so I'd look for a good 2"-eyepiece. Using this without a 2"-eyepiece is like owning a sports car that never gets above 45mph. Personal recommendation? Avoid 40mm/41mm superwides (40ES-68 / 41mm Panoptic); they'll generate too large an exit pupil. A 31T5 would be ideal, but it's very expensive and there's a LOT more deep-sky objects better appreciated with mid-power eyepieces than low-power. A 30ES-82 is a more economical choice; I own one and heartily recommend it. A 34ES-68 or a 28ES-68 are also good choices, and they're reasonably-prices on the used market.
A mid-power eyepiece, between 10mm and 15mm focal length, would be ideal. If you're going to burn $500+ on one eyepiece for this scope, make it a 13mm Ethos, not a 31T5 Nagler. Personally, I prefer to have long eye relief, so I went with the (much cheaper!) 14mm and 10mm Delos. They worked GREAT with this scope, with about the right blend of image scale, brightness and sky contrast. If you don't need to wear glasses to correct for astigmatism, there are MANY good choices for eyepieces in this range, particularly the 14ES-82 and the 8.8ES-82, as well as the 8.8mm Meade 5000 UWA.
Because it's a 1,500mm focal length and 200X-250X seems to be the seeing barrier for many nights in much of the world, any eyepiece below 6mm (250X) is a bit much in the way of power.
I eventually bought a coma corrector (Paracorr), but I ended up using it mostly on my 8" Orion / Lockwood hybrid. If I recall correctly, the Paracorr won't quite bottom out in the 2"-sleeve of the SW focuser, but I don't recall having any problem using it. I used it in tandem one night with an old-style 30mm Meade 5000-UWA. That's *FOUR POUNDS* on the focuser, and, yes, you'll have to tighten the tension control system, but it DID handle it.
I never did astrophotography with the 120-ST refractor. I'll probably get around to astro-imaging right around, oh, never. I don't get many clear nights as is in NE Ohio, and I don't have the temperament nor the finances to burn sizable portions of those precious nights and thousands of dollars only to find out I didn't quiiiiiite get the focus down right, the optics have dewed up, etc.
Just my 1.4-cents' worth. It's be worth 2 cents, but that was before taxes, insurance and 401(k) contributions.
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