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

A SOLID 30 mm F/10 Schmidt Cassegrain

This topic has been archived. This means that you cannot reply to this topic.
61 replies to this topic

#26 ahopp

ahopp

    Messenger

  • -----
  • Posts: 403
  • Joined: 24 May 2012

Posted 05 February 2013 - 10:04 PM

Sorry Tony! So you're actually asking me to make one for you? Ehh.... I'm very flattered! Let me think about it for a while, and I'll answer you by PM. Is that ok for you?


Yes, contact me via PM, very interested in what you have done.

Tony

#27 StarStuff1

StarStuff1

    Skylab

  • *****
  • Posts: 4,155
  • Joined: 01 Apr 2007

Posted 05 February 2013 - 11:31 PM

At first I thought there was a typo and the title should have said "A SOLID 300mm....."

Wow!

Barry Crist of b. crist miniatures could probably make you an appropriate sized mount and tripod.

#28 Astrojensen

Astrojensen

    James Webb Space Telescope

  • *****
  • Posts: 15,203
  • Joined: 05 Oct 2008

Posted 06 February 2013 - 03:40 AM

Barry Crist of b. crist miniatures could probably make you an appropriate sized mount and tripod.



Actual working 1:10 scale model of a 12" f/10 Meade LX200 SCT, with GOTO and Superwedge... :bigshock: :bugeyes: :jawdrop:

:grin:


Clear skies!
Thomas, Denmark

#29 Darenwh

Darenwh

    Mercury-Atlas

  • -----
  • Posts: 2,837
  • Joined: 11 May 2006

Posted 06 February 2013 - 08:19 AM

Well, I think I can stop coming to the ATM thread now. I don't think anybody's going to top this one. Great job...

#30 rik ter horst

rik ter horst

    Messenger

  • -----
  • topic starter
  • Posts: 442
  • Joined: 01 Nov 2010

Posted 06 February 2013 - 02:22 PM

@ Vladova, well, I just discovered a very practical problem: The BFL of the little scope is too short to be able to focus with my DBK21 camera. I could make images at shorter distances however, so whenever I have something to show I'll post it here....

@ Thomas, I agree, it should have goto! Always easy when observing faint distant galaxies ;-)

@ Daren, Many thanks! But.... there are so many creative telescope makers out there, making incredible instruments in all kinds of types, dimensions and quality, I wouldn't stop visiting the ATM threads!

#31 maroubra_boy

maroubra_boy

    Vanguard

  • -----
  • Posts: 2,168
  • Joined: 08 Sep 2009

Posted 06 February 2013 - 04:43 PM

Bloody awesome!


Just what Glenn said!

:yay:

And I thought my C5 was cute - stand aside C5, there's a new kid on the block :bow:

Alex.

#32 tim53

tim53

    James Webb Space Telescope

  • *****
  • Posts: 16,139
  • Joined: 17 Dec 2004

Posted 06 February 2013 - 05:04 PM

This is neat. What is the actual size of the focal plane. Many machine vision cameras have ccds on the order of 1/4" diagonally. If your focal plane is about that big, it might not make a bad e-finder at all! Just make a C-mount thread for it to screw right on the front of the camera.

-Tim.

#33 Dick Jacobson

Dick Jacobson

    Apollo

  • -----
  • Posts: 1,434
  • Joined: 22 Dec 2006

Posted 07 February 2013 - 09:10 AM

If you look through it backwards, does it work as a magnifier?

I agree with everyone, this is AWESOME! Just the right size for Barbie and Ken.

#34 ZeroID

ZeroID

    Ranger 4

  • -----
  • Posts: 396
  • Joined: 21 Apr 2010

Posted 07 February 2013 - 07:07 PM

And I thought the Hubble scope was clever .... !!
Amazing work.

#35 kw6562

kw6562

    Authoritative Ignoramus

  • *****
  • Posts: 988
  • Joined: 25 Jun 2008

Posted 08 February 2013 - 12:42 AM

That is such a cool idea! Great job! :bow:

It reminds me of some catadioptric microscope objectives that I bought for a project at work a few years ago: Newport objectives

--Keith

#36 rik ter horst

rik ter horst

    Messenger

  • -----
  • topic starter
  • Posts: 442
  • Joined: 01 Nov 2010

Posted 09 February 2013 - 03:55 PM

Thank you all!
@Tim, in the first solid cas (shown here) a 1/4 inch ccd could be used although it suffers from field curvature. I've made a new design not so long ago which has a flat useful focal plane of at least 8 x 8 mm and a larger back focal distance. I hope to be able to make it soon.
@Dick, when using it backwards the obstruction makes it kind of useless unfortunately. What is possible however is to use it as a long distance microscope, from 1 meter distance and further....
@Keith, yes you're right, the dimensions are quite comparable. Optically it is a different story, but the microscope objectives you mention are interesting indeed!

Maybe we should ask Barbie and Ken what eyepieces they prefer.
Anyone out there wanting to make a 1.3 mm Ethos?? :-)

#37 azure1961p

azure1961p

    Hubble

  • *****
  • Posts: 13,816
  • Joined: 17 Jan 2009

Posted 09 February 2013 - 06:18 PM

I'm beside myself. I thought for sure your 30mm was a typo for 300mm. Awesome, kudos and all that.

Pete

#38 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 101,347
  • Joined: 16 Jun 2004

Posted 28 April 2015 - 09:59 AM

I just happened on this thread.. As Glenn said, Bloody Awesome. I believe there are designs in Sidgwick for solid Cassegrains but to actually make one.. :tonofbricks:

 

Jon



#39 macdonjh

macdonjh

    Fly Me to the Moon

  • *****
  • Posts: 7,472
  • Joined: 06 Mar 2006

Posted 28 April 2015 - 02:46 PM

Has Rod Molise included it in his SCT book yet?  Some one should tell him about it.  His book is no longer complete.



#40 photiost

photiost

    Gemini

  • *****
  • Posts: 3,248
  • Joined: 14 Dec 2006

Posted 28 April 2015 - 10:56 PM

One of a kind !!  :waytogo:



#41 saemark30

saemark30

    Surveyor 1

  • -----
  • Posts: 1,546
  • Joined: 21 Feb 2012

Posted 01 May 2015 - 04:47 PM

A pocket sized SCT!

Do you happen to have an OSLO or ZEMAX file of the little 30mm or 40mm SCT?

If I was to make one though I would want it to fit a 2" eyepiece so maybe it can be 48mm or so aperture?



#42 diglit

diglit

    Vostok 1

  • -----
  • Posts: 155
  • Joined: 07 Sep 2008

Posted 01 May 2015 - 04:51 PM

W.O.N.D.E.R.F.U.L.

 

One of the best telescopes I've seen.

 

CLAP CLAP CLAP

 

Paolo



#43 mikey cee

mikey cee

    Cosmos

  • *****
  • Posts: 9,589
  • Joined: 18 Jan 2007

Posted 01 May 2015 - 05:11 PM

Great I wondered how and who would come up with the first trend against aperture fever! Yesireeee the next craze for sure!  :waytogo:  :waytogo:  :waytogo:  :bow: Mike



#44 woodscavenger

woodscavenger

    Apollo

  • ****-
  • Posts: 1,121
  • Joined: 20 Aug 2013

Posted 01 May 2015 - 05:50 PM

Is that grab and go, grab and lose, or grab and drop and say where did it go?

 

Make two for bino viewing!!

 

Keychain for sure.  

 

We all want one.   How about a group buy?  Quit your job and start grinding glass.



#45 steveastrouk

steveastrouk

    Apollo

  • *****
  • Vendors
  • Posts: 1,285
  • Joined: 01 Aug 2013

Posted 02 May 2015 - 08:49 AM

This is exceptional craftsmanship, even in the world of ATM. Beautiful work, I am awestruck.

Its when you click on the raytrace diagram, and realise its larger than real-life on a laptop screen.....


Edited by steveastrouk, 02 May 2015 - 09:07 AM.


#46 gdd

gdd

    Mercury-Atlas

  • -----
  • Posts: 2,556
  • Joined: 23 Nov 2005

Posted 02 May 2015 - 02:10 PM

A pocket sized SCT!
Do you happen to have an OSLO or ZEMAX file of the little 30mm or 40mm SCT?
If I was to make one though I would want it to fit a 2" eyepiece so maybe it can be 48mm or so aperture?

Aperture fever?

Gale

#47 Ed D

Ed D

    Aurora

  • *****
  • Posts: 4,939
  • Joined: 30 Apr 2010

Posted 02 May 2015 - 03:42 PM

A miniature achromat or Newtonian would have been intricate and hard enough.

 

A working 30mm SCT?  W O O O W !   :waytogo:  :bow:

 

I also thought the '30mm' was a typo.

 

Ed D


Edited by Ed D, 02 May 2015 - 03:43 PM.


#48 tjay

tjay

    Mercury-Atlas

  • *****
  • Posts: 2,825
  • Joined: 03 Feb 2007

Posted 02 May 2015 - 05:11 PM

This is super cool.  I'd love to know how much they would cost...



#49 Mike I. Jones

Mike I. Jones

    Aurora

  • *****
  • Posts: 4,849
  • Joined: 02 Jul 2006

Posted 03 May 2015 - 01:20 AM

Rik's mini-SCT got me curious about these miniature designs as well.  This design is a quick 30mm f/6 SCT made from fused silica I did in Zemax, but keyed into OSLO-EDU for those interested.  It's a little different than Rik's in that the rear surface is one continuous spherical surface, without the spherical dimple ground and polished into it.  The front surface is a simple 4th order aspheric but still has the central dimple.

 

Interesting design space to explore, thanks Rik!

Mike

 

Attached Thumbnails

  • 30mm f6 solid silica SCT scrip and layout  smaller.png

Attached Files



#50 M.J.P.Meiling

M.J.P.Meiling

    Sputnik

  • -----
  • Posts: 29
  • Joined: 04 Apr 2015

Posted 03 May 2015 - 10:08 AM

Is this the Rik Ter Horst from Opticon-fame in the 1980´s.
Who made the SCT´s in Holland back in the day??




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