Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> ATM, Optics and DIY Forum

Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | >> (show all)
Jim Curry
Pooh-Bah
*****

Reged: 10/29/07

Loc: STL
Re: Post your home made scope new [Re: dave brock]
      #5638309 - 01/23/13 06:54 AM Attachment (218 downloads)

4" f/12 Istar, powder coated, baffled, AP focuser.
Jim


Post Extras: Print Post   Remind Me!   Notify Moderator  
NHRob
Post Laureate
*****

Reged: 08/27/04

Loc: New Hampshire
Re: Post your home made scope new [Re: Jim Curry]
      #5638320 - 01/23/13 07:18 AM

Nice. How are the optics on that 4" Istar?

Post Extras: Print Post   Remind Me!   Notify Moderator  
John Jarosz
Astro Gearhead
*****

Reged: 04/25/04

Loc: Fairfax, Iowa
Re: Post your home made scope new [Re: NHRob]
      #5638401 - 01/23/13 08:31 AM Attachment (185 downloads)

Here are the 3 scopes in my sig line

Post Extras: Print Post   Remind Me!   Notify Moderator  
tim53
Postmaster
*****

Reged: 12/17/04

Loc: Highland Park, CA
Re: Post your home made scope new [Re: John Jarosz]
      #5638682 - 01/23/13 11:05 AM

This was my first home-made scope. No jive!

8" f/6 Springfield Newtonian, 1981 RTMC Merit award winner.



-Tim


Post Extras: Print Post   Remind Me!   Notify Moderator  
droid
rocketman
*****

Reged: 08/29/04

Loc: Conneaut, Ohio
Re: Post your home made scope new [Re: tim53]
      #5638712 - 01/23/13 11:20 AM

Some beautiful scopes so far. to all

Post Extras: Print Post   Remind Me!   Notify Moderator  
VĂ­ctor MartĂ­nez
sage


Reged: 02/05/07

Loc: Cadiz - Spain
Re: Post your home made scope new [Re: droid]
      #5638733 - 01/23/13 11:31 AM

Here the mine, 16" f5



Post Extras: Print Post   Remind Me!   Notify Moderator  
idp
sage


Reged: 08/21/09

Loc: New Haven, CT
Re: Post your home made scope new [Re: droid]
      #5638735 - 01/23/13 11:33 AM

Awesome thread, I learned a lot just by scrolling down.

Mike, I fell in love with your ball mount but frankly, how hard is it to collimate with the trusses instead of the primary mirror?


Ivano


Post Extras: Print Post   Remind Me!   Notify Moderator  
droid
rocketman
*****

Reged: 08/29/04

Loc: Conneaut, Ohio
Re: Post your home made scope new [Re: VĂ­ctor MartĂ­nez]
      #5638831 - 01/23/13 12:28 PM

Victor , like the 16" f/5 on the focuser board, burned in???

Post Extras: Print Post   Remind Me!   Notify Moderator  
VĂ­ctor MartĂ­nez
sage


Reged: 02/05/07

Loc: Cadiz - Spain
Re: Post your home made scope new [Re: droid]
      #5638910 - 01/23/13 01:09 PM

Andy, is a black vinyl adhesive

Post Extras: Print Post   Remind Me!   Notify Moderator  
StarWrangler
scholastic sledgehammer


Reged: 09/03/04

Loc: Three Rivers, MI U.S.A>
Re: Post your home made scope new [Re: John Jarosz]
      #5638938 - 01/23/13 01:25 PM

Cool,

The one open Scope reminds me of D. Dillworths Dall Kirkham Folding scope that was in Sky & Telescope some years ago.

Alan O.


Post Extras: Print Post   Remind Me!   Notify Moderator  
mconnelley
sage


Reged: 03/14/06

Loc: Hilo, HI
Collimating using the truss new [Re: idp]
      #5639021 - 01/23/13 02:36 PM

Hello:

Collimating the ballscope using the trusses is fairly easy, but a little different than a 'regular' Newtonian. On the plus side, there is no running back and forth since everything is done at the top end. If I get set up before dark, I use a regular Cheshire collimating tool to collimate the secondary and then the primary in the usual way, and that gets me pretty close. Then I look at a star to zero out the coma by adjusting the truss. I look at the star out of focus, and stick my hand into the beam and move it around until the shadow of my hand is on the 'thin' side of the donut (out of focus image of the star). I then know which way I need to move the truss. After a few iterations, the coma has been taken care of. Overall, I'd say that it's no harder than collimating a 'regular' f/4 Newtonian. The collimation seems to hold well throughout a night.

The reason I put the collimation at the top was to allow me to put the mirror farther back into the ball, thus helping balance. The hardware, plus room to allow for the adjustment, would have taken up about 1" of space back there. Also, since the mirror doesn't move relative to the ball, the mirror edge supports are glued to the inside of the ball, and aren't attached to the part of the mirror cell with the triangles and bars. So, from a certain point of view, the ball is also the frame for the mirror cell.

Cheers
Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
philipdo
sage


Reged: 12/06/06

Loc: Flanders, Belgium, Europe
Re: Post your home made scope new [Re: StarWrangler]
      #5639066 - 01/23/13 03:10 PM Attachment (216 downloads)

My trusted 200 mm F/D 20 Kutter Catadioptric Schiefspiegler. Wood & aluminum construction.

Post Extras: Print Post   Remind Me!   Notify Moderator  
idp
sage


Reged: 08/21/09

Loc: New Haven, CT
Re: Collimating using the truss new [Re: mconnelley]
      #5639071 - 01/23/13 03:11 PM

Very interesting, thank you. You says that the collimation holds through the night, does it mean that you'll have to repeat it on the following observing night? Even if you do not disassemble the the telescope?

Ivano


Post Extras: Print Post   Remind Me!   Notify Moderator  
roscoe
curmudgeon
*****

Reged: 02/04/09

Loc: NW Mass, inches from VT
Re: Post your home made scope new [Re: philipdo]
      #5639780 - 01/23/13 11:35 PM Attachment (188 downloads)

Here's my 60mm f/16.... a Carton objective, long tube made by splicing together two tubes, vintage .965 focuser, dew shield made from a fire extinguisher, Meade alt-az mount found in a customer's basement, used aluminum tripod, now replaced with a home-made cherry wood model.

Post Extras: Print Post   Remind Me!   Notify Moderator  
kfiscus
Carpal Tunnel
*****

Reged: 07/09/12

Loc: Albert Lea, MN, USA
Re: Post your home made scope new [Re: roscoe]
      #5639806 - 01/23/13 11:55 PM Attachment (155 downloads)

My redone rockerboard for my Z12. Shortened, lightened, prettified.

Post Extras: Print Post   Remind Me!   Notify Moderator  
kfiscus
Carpal Tunnel
*****

Reged: 07/09/12

Loc: Albert Lea, MN, USA
Re: Post your home made scope new [Re: kfiscus]
      #5639811 - 01/23/13 11:59 PM Attachment (154 downloads)

Side view of same. M31 and friends? Top hole (M32) is functional for C5 solar viewing scope, bottom hole (M110) is handle. Rides on dedicated Atomic EQ platform.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Jim Curry
Pooh-Bah
*****

Reged: 10/29/07

Loc: STL
Re: Post your home made scope [Re: NHRob]
      #5639823 - 01/24/13 12:07 AM

Rob:

As one critical observer noted "that the CA for an 4" f/12 was about as good as it gets. The rings were concentric and perfectly shaped" and " this looks lens like it was turned on a lathe, perfect star test images and as good as a 4" achromat can be. He was even speculating that maybe the glass was special and that this wasn't a Fraunhofer design to get such good correction."

It doesn't get better in a 4" than what this scope puts up. I built up a 6" f/12 Istar and I say the same thing.

Jim


Post Extras: Print Post   Remind Me!   Notify Moderator  
Crayfordjon
Vendor - Zerochromat
*****

Reged: 06/17/09

Loc: UK
Re: Post your home made scope [Re: Jim Curry]
      #5639991 - 01/24/13 03:36 AM Attachment (233 downloads)

Six inch refractor made from cat food tins and plastic drain pipes, used for solar imaging.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Bob Myler
Carpal Tunnel
*****

Reged: 05/18/06

Loc: St Louis, MO
Re: Post your home made scope [Re: Crayfordjon]
      #5640971 - 01/24/13 04:03 PM

Quote:

Six inch refractor made from cat food tins and plastic drain pipes, used for solar imaging.




Friskies, Fancy Feast - or Tender Vittles?


Post Extras: Print Post   Remind Me!   Notify Moderator  
titanio
sage


Reged: 02/15/09

Loc: Alicante, Spain
Re: Post your home made scope [Re: Bob Myler]
      #5641124 - 01/24/13 05:37 PM

here is mine I will finish it soon



Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | >> (show all)


Extra information
13 registered and 19 anonymous users are browsing this forum.

Moderator:  ausastronomer, richard7, Starman81 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 44720

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics