"Best" large aperture OTA?

[Tulloch]

So I'm starting to get aperture fever again, and am looking at a 12" OTA for a mixture of planetary and DSO imaging. The criteria are for a scope that's fast, light, cheap (I know, choose any 2 :lol:). While an SCT or RC is short, they are heavy, expensive and slow. A Newtonian is fast, but long and heavy. A refractor with any aperture is fast but outrageously expensive.

So I guess I'm stuck with a "short" Newtonian at f/4, but the GSO versions do not have a good reputation at holding collimation, the SkyWatcher is heavy and the one I'd really like, the TS Optics carbon fibre is pretty expensive (even shipping to Australia is $A1000 :eyepop:). Any then there's the extra cost for a coma corrector etc.

What am I missing? Are there any other manufacturers of carbon fibre Newtonians in a 12" diameter that are any good?

Thanks, Andrew

[Startrek]

I bought both 10” and 8” Klaus Helmerich Carbon fibre OTA’s ( tube only ) through Sidereal Trading in Melbourne and retrofitted my own GSO focusers , spider and mirrors etc…
Ended up with good quality light weight imaging Newts . I use f5 , too many issues with f4 tube newts , f5 is faster enough for DSO and Planetary in my experiences
Sidereal Trading are now making their own carbon fibre 10” and 12” newts in f4 and f5 as well
Give Paul or Diego a call

Cheers
Martin

[glend]

I agree an f5 Newt is a great option. And I have had three different sizes GSO Newts 8, 12 and 16, all f5 and collimation was rock solid. It's at f4 that newts start to have issues. As to light weight, I built my own carbon strut 10" f5 Newt, using a GSO mirror set, and it was a great scope, and very light. Strut tubes are easy to build, you can buy carbon tubes online in Australia, and the resin products you need. You would need to build a jig but it's not hard. You can probably still find my build thread in the archives here at IIS.

Have fun.

[Tulloch]

Thanks, Sidereal Trading appear to have a 12" f/4 on their website, I might enquire about an f/5...

[Derek Klepp]

Andrew I have always been impressed with your planetary images with your scopes.I know Steve Massey gets world class images with a 12” Skywatcher Newt.But imagine what you would get with a C14.I realise this may be out of your price range.But remember life is short.
Cheers Derek.

[Tulloch]

Thanks, maybe one day...

[By.Jove]

I’ve admired the scopes from Sumerian Optics (12-16” and yes f/5) but can’t really justify one…

[Camelopardalis]

Hey Andrew, given your outstanding results with your current scope, I'd be reluctant to take the gamble with another TBH.

I'm not convinced there's a good competitor for a C14 that, with all engineering issues addressed, is significantly cheaper and as easy to use.

Just my 2c...

[Tulloch]

Thanks again, the C14 is pretty much the best "consumer" OTA out there for planetary, and some of the best images I've seen of the planets have been taken with it. However, the size, weight and cost are too prohibitive for me at the moment, and others in my Astro club are taking really nice images with a 12" Newt, with significantly more detail than my 9.25 is capable of.

Is that little bit extra worth it? Not sure. Maybe I need to travel out of the suburbs and try to catch some better seeing...

[Camelopardalis]

Yeah with a newt comes a lot of grief, unless it’s well-engineered. Too many degrees of freedom. May be great in one part of the sky but not in another, unless it’s really done well. Similarly, I don’t think you’d benefit much from a C11, despite the greater ease of collimation.

Seeing us the great equaliser of course… the way I see it is that, the bigger the scope the rarer it gets to strut its stuff… but then I’m not far from the ocean. We gotta work with what we got :D