Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

10" f9 APO

  • Please log in to reply
78 replies to this topic

#51 John Fitzgerald

John Fitzgerald

    In Focus

  • *****
  • Posts: 10,904
  • Joined: 04 Jan 2004
  • Loc: near Elkins and Pettigrew, Arkansas

Posted 29 November 2021 - 03:30 PM

Sounds like larger refractors would not fare well in a standard dome, like Ash Dome, due to thermal issues.  I like domes for refractors, due to protection from dew, local lighting,  and wind.  But, how do you insulate the dome itself?



#52 Jeff B

Jeff B

    Cosmos

  • *****
  • Posts: 8,246
  • Joined: 30 Dec 2006

Posted 29 November 2021 - 08:57 PM

Sounds like larger refractors would not fare well in a standard dome, like Ash Dome, due to thermal issues.  I like domes for refractors, due to protection from dew, local lighting,  and wind.  But, how do you insulate the dome itself?

Yeah, each type of observatory has its advantages and disadvantages.  Our Parks District's 8.75" F12 achromat is housed in a fiberglass dome that sits on top of a heavily insulated silo style base.  The interior walls are indeed cool but heat builds above the walls, enough so that we get thermals out of the shutter slit for the first hour on top of the scope cooling down.  

 

However, interior dew or frost have never been issues and it is subjectively much more comfortable in the dome as our bodies don't radiate nearly as much heat as they do when we are outside.  I too have been thinking of ways to insulate the dome itself but I don't want to make the thermal situation any worse.  The first thing is to paint the outer surface with aluminum paint.

 

Jeff

 

BTW, I still have not given up on the idea of a LZOS 9" F9 objective with an ATM OTA as an interim scope before the TEC is ready.

 

Jeff


  • peleuba, zjc26138 and Astrojensen like this

#53 fate187

fate187

    Viking 1

  • *****
  • Posts: 611
  • Joined: 16 May 2015
  • Loc: Germany

Posted 30 November 2021 - 06:42 AM

DPAC it is then, it was mentioned here. Looking forward to it! Hope you have a flat large enough Jeff :D. And looking forward to observing reports. It should come handy for the next planetary season in 2022, the scope I mean :).

 

best wishes


  • Jeff B likes this

#54 zjc26138

zjc26138

    Loved By All

  • *****
  • Posts: 9,653
  • Joined: 24 Feb 2005
  • Loc: Steubenville, Ohio

Posted 30 November 2021 - 09:58 AM

I think I need to make a trip to southern Ohio to see this 10" apo in person. :)



#55 StarAlert

StarAlert

    Surveyor 1

  • *****
  • Posts: 1,989
  • Joined: 11 Aug 2019
  • Loc: SoCal

Posted 30 November 2021 - 10:03 AM

I would make a point to stop by if I was in the area. lol.gif



#56 stevenwav

stevenwav

    Viking 1

  • *****
  • Posts: 783
  • Joined: 06 Feb 2012
  • Loc: New England

Posted 30 November 2021 - 01:23 PM

I wonder if Yuri will be bringing his 10" f/9 to the Winter Star Party in February - he is very accommodating and that is a great opportunity to catch a gander of the views in hopefully fantastic conditions. I had a great view of Jupiter with it a few years back. I'm excited for you Jeff!


Edited by stevenwav, 30 November 2021 - 01:25 PM.


#57 Astrojensen

Astrojensen

    Hubble

  • *****
  • Posts: 14,675
  • Joined: 05 Oct 2008
  • Loc: Bornholm, Denmark

Posted 30 November 2021 - 03:59 PM

I wonder if I will ever get the chance to look through a 10" apo in good seeing. 

 

 

Clear skies!

Thomas, Denmark



#58 dothead

dothead

    Apollo

  • -----
  • Posts: 1,174
  • Joined: 13 Aug 2008
  • Loc: Heidelberg, Germany

Posted 30 November 2021 - 04:44 PM

... My only real thing that gave me a bit of pause is the fact that TEC and APM 10" F9 triplets are both air spaced designs and I have some mild concerns regarding the thermodynamics of such a larger aperture air spaced objective. ...

 

Jeff

In this respect, the 10" F12  CaF2 doublet offered by Aries Optical would be an alternative ...


  • Astrojensen likes this

#59 BRCoz

BRCoz

    Apollo

  • *****
  • Posts: 1,338
  • Joined: 21 Oct 2005
  • Loc: Moreno Valley, CA

Posted 30 November 2021 - 05:08 PM

Star party at Jeff's next year!   LOL

 

 

Enjoy the scope.


  • doctordub, 39.1N84.5W, Astrojensen and 1 other like this

#60 39.1N84.5W

39.1N84.5W

    He asked for it

  • *****
  • topic starter
  • Posts: 4,397
  • Joined: 24 Oct 2006
  • Loc: cincinnati

Posted 30 November 2021 - 05:20 PM

Star party at Jeff's next year! LOL


Enjoy the scope.


He runs two different observatories with big refractors... I think a Warren County star party in 2022 is a GREAT idea!
  • Dagobert and BRCoz like this

#61 CHASLX200

CHASLX200

    ISS

  • *****
  • Posts: 25,415
  • Joined: 29 Sep 2007
  • Loc: Tampa area Florida

Posted 30 November 2021 - 07:06 PM

I wonder if I will ever get the chance to look through a 10" apo in good seeing. 

 

 

Clear skies!

Thomas, Denmark

I have never even seen a 7" APO ever in my life. They are just not in FL i guess. 



#62 Jeff B

Jeff B

    Cosmos

  • *****
  • Posts: 8,246
  • Joined: 30 Dec 2006

Posted 30 November 2021 - 07:25 PM

I wonder if I will ever get the chance to look through a 10" apo in good seeing. 

 

 

Clear skies!

Thomas, Denmark

Me too!  grin.gif


  • peleuba and Astrojensen like this

#63 Jeff B

Jeff B

    Cosmos

  • *****
  • Posts: 8,246
  • Joined: 30 Dec 2006

Posted 30 November 2021 - 07:26 PM

In this respect, the 10" F12  CaF2 doublet offered by Aries Optical would be an alternative ...

Unfortunately, that's just too long of a scope for my situation.

 

Actually, I almost got an Aries 10" F9 FL triplet objective a few years ago Markus was offering for sale at an extremely attractive price (for a 10" F9 FL triplet anyway).  It had a small cleave at the very edge of the FL element outside the light path that Valery smoothed out.  Valery really encouraged me to get it.   But I chickened out.  Actually, I didn't know at the time that being on a corner lot, I had an exception to the zoning rules which allows me to have a "detached accessory" structure in my side yard.  Normally such structures are relegated to the backyard, which in my case just would not work.  If I had known that at the time the objective became available, I probably would have gotten it.

 

Jeff


Edited by Jeff B, 30 November 2021 - 07:36 PM.

  • Scott in NC likes this

#64 Mbenj2405

Mbenj2405

    Vostok 1

  • *****
  • Posts: 113
  • Joined: 03 Mar 2019
  • Loc: head Chezzetcook Nova Scotia Canada

Posted 01 December 2021 - 08:42 AM

I have sure tried to find a pre GO-TO 1200 for years and no luck.

There is a 1200 FS on Ebay right now. Seller has it listed as a GTO but it isn't. Probably a SMD. 

https://www.ebay.ca/...f8AAOSwSwphoSXl


  • StarAlert likes this

#65 Alan French

Alan French

    Night Owl

  • *****
  • Posts: 6,385
  • Joined: 28 Jan 2005
  • Loc: Upstate NY

Posted 02 December 2021 - 06:29 PM

I have never even seen a 7" APO ever in my life. They are just not in FL i guess. 

There always seems to be a good selection of apochromats at Winter Star Party in the Florida Keys, often including larger models. And the seeing can be excellent, which requires looking through scopes with significant aperture too. ;)

 

Clear skies, Alan


  • peleuba likes this

#66 CHASLX200

CHASLX200

    ISS

  • *****
  • Posts: 25,415
  • Joined: 29 Sep 2007
  • Loc: Tampa area Florida

Posted 02 December 2021 - 07:06 PM

There always seems to be a good selection of apochromats at Winter Star Party in the Florida Keys, often including larger models. And the seeing can be excellent, which requires looking through scopes with significant aperture too. wink.gif

 

Clear skies, Alan

I was meaning local to me and for sale. I am sure there is every scope under the sun down there but way too far for me to drive.



#67 B 26354

B 26354

    Vanguard

  • *****
  • Posts: 2,285
  • Joined: 05 Jan 2017
  • Loc: Southern California semi-desert (NELM mag 5.3)

Posted 02 December 2021 - 08:44 PM

There is a 1200 FS on Ebay right now. Seller has it listed as a GTO but it isn't. Probably a SMD. 

https://www.ebay.ca/...f8AAOSwSwphoSXl

???

 

That link leads to a Celestron Nexstar 8



#68 Astrojensen

Astrojensen

    Hubble

  • *****
  • Posts: 14,675
  • Joined: 05 Oct 2008
  • Loc: Bornholm, Denmark

Posted 03 December 2021 - 04:32 PM

???

 

That link leads to a Celestron Nexstar 8

Even more ????

 

The first time I followed the link, it got me to the correct page, with an A-P 1200 mount. Now it leads to a Takahashi FSQ-106!!!  shocked.gif  And the seller is not the same, either!! confused1.gif

 

 

Clear skies!

Thomas, Denmark



#69 John Fitzgerald

John Fitzgerald

    In Focus

  • *****
  • Posts: 10,904
  • Joined: 04 Jan 2004
  • Loc: near Elkins and Pettigrew, Arkansas

Posted 03 December 2021 - 04:35 PM

Even more ????

 

The first time I followed the link, it got me to the correct page, with an A-P 1200 mount. Now it leads to a Takahashi FSQ-106!!!  shocked.gif  And the seller is not the same, either!! confused1.gif

 

 

Clear skies!

Thomas, Denmark

Looks like a scam, doesn't it?  I don't trust ebay, unless the seller is an established retail outlet.


  • fred1871 likes this

#70 gnowellsct

gnowellsct

    James Webb Space Telescope

  • *****
  • Posts: 19,745
  • Joined: 24 Jun 2009

Posted 06 December 2021 - 01:18 PM

It's worth it.  Cheaper and more fun than a lambo and definitely attracts the ladies.


  • Scott Beith, doctordub, Jeff B and 1 other like this

#71 mrkellytaylor

mrkellytaylor

    Lift Off

  • -----
  • Posts: 6
  • Joined: 05 Nov 2015

Posted 11 December 2021 - 09:17 PM

I own a 6 inch F/15 old school refractor.
On the moon and planets under my light polluted skies in South East Texas.
I enjoy every minute I get to view with it.
I have done lots of double stars as well.
I also have a ACH 204mm F/9 refractor.
they are wonderful instruments.
I also had built a 6 inch F/5 ach as well on a AVX mount. Which easy for looks at all kinds of stuff.
Enjoy your refractors.
The only thing better then a refactor is a bigger refractor.
  • John Fitzgerald, 3 i Guy, doctordub and 9 others like this

#72 Thomas_M44

Thomas_M44

    Apollo

  • -----
  • Posts: 1,210
  • Joined: 14 Feb 2020
  • Loc: Modesto, CA USA

Posted 13 December 2021 - 02:41 PM

I own a 6 inch F/15 old school refractor.
On the moon and planets under my light polluted skies in South East Texas.
I enjoy every minute I get to view with it.
I have done lots of double stars as well.
I also have a ACH 204mm F/9 refractor.
they are wonderful instruments.
I also had built a 6 inch F/5 ach as well on a AVX mount. Which easy for looks at all kinds of stuff.
Enjoy your refractors.
The only thing better then a refactor is a bigger refractor.

It seems to me the physics supports the optical supremacy of (high quality) refractors over essentially all other telescope types up to at least 300mm of aperture.

 

Cost and size (length), these appear to be the only substantial caveats not favoring such large refractors.


Edited by Thomas_M44, 13 December 2021 - 02:45 PM.


#73 Gleason

Gleason

    Ranger 4

  • *****
  • Posts: 391
  • Joined: 03 Jan 2013
  • Loc: SF Bay Area

Posted 13 December 2021 - 03:08 PM

GM3000 folks for this OTA.  And get the tripod and pier extension Yuri shows with his.  There was a bit of a compairson done between the 10 f/9 and a pair of 10" f/14.5 AP Mas-cass at the Winter SP a few years ago.  I would have loved to have seen that.  Somewhere there are mount and telescope assembly at the WSP.  It's a beast.  



#74 Jeff B

Jeff B

    Cosmos

  • *****
  • Posts: 8,246
  • Joined: 30 Dec 2006

Posted 15 December 2021 - 12:03 PM

GM3000 folks for this OTA.  And get the tripod and pier extension Yuri shows with his.  There was a bit of a compairson done between the 10 f/9 and a pair of 10" f/14.5 AP Mas-cass at the Winter SP a few years ago.  I would have loved to have seen that.  Somewhere there are mount and telescope assembly at the WSP.  It's a beast.  

The GM3000 would be a fine mount as would the AP1600.  

 

The mounts I have on hand, my AP1200 and MI-500, should do just fine, with the MI-500 particularly capable.  The only downside to the MI-500 (which uses the AP servo system) is that making fine altitude and azimuth adjustments for polar alignment is a bit of a PITA, where those adjustments with the AP is super easy.    I'll be using the steel pier I have now, filled with sand, sitting on top of a 14" concrete pedestal, itself plugged into an 8" thick, reinforced, slab. 

 

If you can post a link thing to that WSP comparison, that would be most appreciated by all.

 

Jeff

Attached Thumbnails

  • AP 1200 GTO A.jpg
  • Assembled and Installed.jpg
  • Day Time Polar Alignment.jpg

  • Scott Beith, EricCCD, 39.1N84.5W and 6 others like this

#75 mrkellytaylor

mrkellytaylor

    Lift Off

  • -----
  • Posts: 6
  • Joined: 05 Nov 2015

Posted 16 December 2021 - 06:14 PM

Oh forgot to mention That Joe at
Parallax Instruments built my
built my 3 Refractors.
204mm FL/1800mm
150mm FL/2250
150mm FL/750

Edited by mrkellytaylor, 16 December 2021 - 06:16 PM.

  • Defenderslideguitar likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics