Barry, that's a serious case of Dob Addiction! How do you decide which one to use, or are you running between them?
He used to bring all three of them out and set them up, which again should be an indication of how relatively painless setting up a dob is. But I think the fact that the 28 always beats even a magical zambuto 20" is the reason I only ever see the Webster these days :-).
And even after setting all his scopes up he'd have time to sit down and chuckle at me being garrotted by a USB cable while wrestling with my equatorial...
Cheers
Andrew.
I use the 20"f4 Ultralight and the 28"f4.2 Webster the most. The 16" f4.5 Dobstuff and 18"f4.2 Plettstone I use less often because Aperture rules .
I used to have a 16" Lightbridge but I threw it down the tip because it was rubbish. If you want a good dob buy a secondhand premium or brand new. I feel my aperture fever is sated for the moment but never say never .
I use the 20"f4 Ultralight and the 28"f4.2 Webster the most. The 16" f4.5 Dobstuff and 18"f4.2 Plettstone I use less often because Aperture rules .
I used to have a 16" Lightbridge but I threw it down the tip because it was rubbish. If you want a good dob buy a secondhand premium or brand new. I feel my aperture fever is sated for the moment but never say never .
You need to break the 30" barrier Barry...
You could always sell the questar :-)
To go back a couple of pages. Budget is really my only stopper in getting something really big. Every time I get a look through a big dob I am just blown away by the difference in detail and brightness compared to my C925.
If I had the budget I would have an obs by now and it would have a couple of piers and a large enough unoccupied area to house a great big dob.
C'mon Andrew you know the 30" barrier is impossible to break. The mass of money required now is so large that it would instantly collapse into a debt singularity destroying all other scopes, eyepieces, Questars or even Unitrons in the vicinity.
I can't sell the Questar anyway I need it to chock the trailer.
Perhaps single piece mirrors are all that is holding you back. If you went to a James Webb type design using mirror tiles the only constraint would be your ability to construct a supporting framework. Imagine arriving at a site with your trailer and pushing a button to have your folded mirror array unfurl like a blooming flower. That will put the other big dobs in the shade.
On that note, what does the future look like for larger transportable scopes?
I feel my aperture fever is sated for the moment but never say never .
Get into bino Newts and you can relive the whole aperture fever journey again , but with more field of view per square inch of total optical surface area
Get into bino Newts and you can relive the whole aperture fever journey again , but with more field of view per square inch of total optical surface area
Perhaps a little off topic but what would motivate one to own such a large telescope?
Is this still just a hobby or do you actively participate in global astronomy efforts? Perhaps the near earth object type program or something like that?
Or is this still a personal hobby for the owners of these very large telescopes?
I am not being critical? Quite the contrary, I would love to have something like this if I could afford it and if I had a place for it.
So why such large scopes?
Ed, for me it is a hobby. But it's not "just a hobby". I love getting outside - well in my observatory anyway, under a starry sky and fresh air. Radio going. Coffee in the thermos. For me, it represents freedom. And if I am first to see a star erupt, or be first to pick up a fade of RCBs (I observe close binary stars called U Gem variables, and carbon stars called R CrBs) it is exciting. There was one star that I was first to see erupting in over 50 years.
I am a member of AAVSO and it's great to be part of the wider international community of amateurs.
I am retired and live by myself so I can stay up as late as I like.
Looking forward to getting my big scope. It will be FUN!!!
Quite right, my mistake, it does seem to be a Push To rather than GoTo.
Hi Matt,
The Mary Rose has Argo Navis DSC's with 10K encoders, but it does not have Servocat drives on it. The Servocat Drives on their own are worth > $3,000. As someone else mentioned a 20" mirror alone is well north of $10k let alone a complete premium telescope structure with a known exceptional quality mirror. The Mary Rose is a bargain at the asking price.
Here is our arsenal of telescopes we supply at Ozsky every year. Every scope bar one (my 14"/F4.5) requires a ladder. Some larger than others.
The largest scope on the field is a 30"/F4.6 SDM which has an eyepiece height of just over 12 feet at the zenith.
This is what the American visitors want, they spend a lot of money to come here and observe the wonders of the Southern Sky. They are all very experienced observers. They don't come to observe through 4" refractors (nice finderscopes), they come here to observe through large aperture high quality dobsonians from 14" to 30" in aperture.
Cheers
John B
Last edited by ausastronomer; 16-07-2016 at 07:54 PM.
This is me up the ladder at the eyepiece of the 30"/F4.6. Being a short arse this scope gets my feet a long way off the ground when pointed near the zenith. Well worth the climb for the views it provides. Not quite the "Stairway to Heaven".
This is me at the eyepiece observing M51 in Larry Mitchell's 36"/F5 Obsession at TSP in 2007. The image was taken by Alan Dyer.
This scope has an eyepiece height in excess of 15 feet at the zenith. The climb up the ladder seems never ending, as does the climb down. Climbing up the ladder and observing can be quite a daunting experience. Many observers get 1/2 way up the ladder and freeze. it's not an easy thing to do in the dark for people not used to climbing ladders to observe. The views are something to behold and oh so worth the climb.
For size reference the finderscope (the white telescope on the mirror box) is a 6" Newtonian (A 1980's vintage Celestron Comet Catcher).
Here is our arsenal of telescopes we supply at Ozsky every year. Every scope bar one (my 14"/F4.5) requires a ladder. Some larger than others.
The largest scope on the field is a 30"/F4.6 SDM which has an eyepiece height of just over 12 feet at the zenith.
This is what the American visitors want, they spend a lot of money to come here and observe the wonders of the Southern Sky. They are all very experienced observers. They don't come to observe through 4" refractors (nice finderscopes), they come here to observe through large aperture high quality dobsonians from 14" to 30" in aperture.
Cheers
John B
The photo you included gave me chills. So much big glass!
I had an opportunity to attend a club observation night on Thursday and there was a 20", masked to 19", truss Dob that was set-up, complete with rolling staircase. Some really nice views. They keep it in a locked building on the site and roll it out when they want to use it.
So, big scope guys, where do you keep them? How do you use them?
I have figured out that I can fit a 14" Orion XXL14I or G on a cart in my garage and just clear the garage door to roll it out to my sidewalk observation location. So, for now, that would be as big as I would go.
If I had a 20+ inch beauty I would want to use it as often as possible.
I presume you have some kind of observatory where your big scopes lives, all set-up and ready to go.
I understand that a truss design can be taken apart and moved but I am sure you are not taking 20+ inch scopes out, building them, observing for an hour or two then taking them apart to put away.
Do you keep them set-up and use them often? Or do you have a 10" Skywatcher sitting in the garage, hidden so no one will know, that you use every day and these are just for national holiday celebrations?
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