12" Refractor in Making

MCYM · Post by **MCYM** » Mon Dec 20, 2004 5:45 pm

Hi to All

Just like to share the joy

This year Christmas present came early. My US friend sent me a monsterous 12" f3.5 triplet and naturally, i was a over the roof.

As a co-owner, we have engage the help of contractor to fabricate an make shift wooden OTA for testing before proceeding to a aluminium version. The finish product will remain quite portable and fit into any car. Total OTA design weight would not to exceed 25kg with the lens itself standing at 15kg

Most likely this project that will keep my hand full for months. Of course, once it is completed, everyone will have a chance to look through it during future starparties.

Matthew

MCYM · Post by **MCYM** » Mon Dec 20, 2004 5:47 pm

Opps.. moderator, wrong forum headings. Should be ATM instead.

Post by **weixing** » Mon Dec 20, 2004 6:19 pm

Hi,
WOW!!! A 12" F3.5 Triplet.... :k-inlove: :k-inlove: :k-inlove:
Your friend must be Bill Gate, right :k-woohoo: ??

WOW!!! Then it will be the largest Triplet Refractor in Singapore, South East Asia or even Asia make by Amateur!!! :-k-yeah:

:drool: :drool: :drool: I'm getting dehydrated :k-shock: :k-lol:

Have a nice day.

MCYM · Post by **MCYM** » Mon Dec 20, 2004 6:50 pm

Hi WeiXing

Bill Gate.... i wish.

It's a military surlpus lens. It did not cost us a fortune but it is beleive it cost the tons of $ to produce a lens of this focal ratio.

Hope to finish building it by new year.
Will post pictures shortly

Matthew

kayheem · Post by **kayheem** » Mon Dec 20, 2004 10:02 pm

MCYM wrote:Hi to All

Just like to share the joy

This year Christmas present came early. My US friend sent me a monsterous 12" f3.5 triplet and naturally, i was a over the roof.

As a co-owner, we have engage the help of contractor to fabricate an make shift wooden OTA for testing before proceeding to a aluminium version. The finish product will remain quite portable and fit into any car. Total OTA design weight would not to exceed 25kg with the lens itself standing at 15kg

Most likely this project that will keep my hand full for months. Of course, once it is completed, everyone will have a chance to look through it during future starparties.

Matthew

THUNK....ooops...that was my jaw dropping and hitting the floor. Wow! a 12" refractor! What focuser will you be using?

Kamikazer · Post by **Kamikazer** » Mon Dec 20, 2004 10:25 pm

its a deep-sky astrograph!!!
madness!!!

Post by nF » Mon Dec 20, 2004 10:30 pm

*Topic moved

Post by **Airconvent** » Mon Dec 20, 2004 11:25 pm

Hi Matt,
My goodness! 12"???? That's like even better than a 10" SCT and without the contrast penalty too. Cool, man.
PLEASE remember to post step by step pictures from its design , fabrication, installation and testing. (maybe a shot of you designing at a table?!!)

good luck on your project !

rich

MCYM · Post by **MCYM** » Tue Dec 21, 2004 12:44 am

Thank you for your well wishes.

Will certainly keep you guys updated while i am anxiously looking fwd to look through it.

Ideally a 4" focuser would fit the bill, but sadly they dont come cheap. So in the meantime a 2" focuser will take its place although it cuts a little into the light cone.

Btw here are some preview pictures.
http://pachome1.pacific.net.sg/~audiowo ... tm#Triplet
(May take a while to load)

I am not sure it could qualify as an astrograph yet. To do so, it has to be flatfield to certain extend of the image circle.
Nonetheless it should be a perfect instrument for narrow band imaging with line filters such as OIII, Ha, SII etc to mitigate CA influence.
That is... if i could borrow a hefty mount to track it.

Matthew

MooEy · Post by **MooEy** » Tue Dec 21, 2004 6:26 am

yeah, seems to me that it is a wonderful narrow band imaging platform. 1000mm of focal length seens just nice for nebs. the high contrast system allows imaging of fainter objects. do keep us inform of ur progress.

~MooEy~

SingAstro

12" Refractor in Making

12" Refractor in Making

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