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Shortest APO?

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#1 FishInPercolator

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Posted 14 May 2013 - 10:59 AM

80mm seems to be around 17" and 102mm around 26" ... can they get shorter?

#2 tomcody

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Posted 14 May 2013 - 11:20 AM

Tak FSQ85 12.7"
Tak FSQ106ED 16.7"

#3 FishInPercolator

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Posted 14 May 2013 - 11:22 AM

sheesh, 5k :)

#4 Cotts

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Posted 14 May 2013 - 11:31 AM

Hi, Neil. Welcome to CN. Who's that guy with you?

Srsly, 80 mm isn't going to get you much deep sky visually but as a camera lens the 80mm aperture is wonderful.

I have an 80 mm Fluorite doublet that cost under $1000 and shows no false colour in photos up to 5 minutes or more.... You don't have to spend the big bucks....

Dave

#5 FishInPercolator

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Posted 14 May 2013 - 11:42 AM

lol...

thanks... Explore Scientific has a 102 carbon fiber that weighs 7 lbs for 1499... I was originally considering an 8" EdgeHD for dso observing but at 14 lbs it requires a tripod that weights at least 40 w/counterweight. So perhaps this is a more viable solution

#6 Scott Beith

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Posted 14 May 2013 - 11:45 AM

TMB 92SS

https://www.astronom...actor-optica...



"ultra-short 13.25” length for travelling"

#7 Gregg Carter

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Posted 14 May 2013 - 07:39 PM

Hi, Neil. Welcome to CN. Who's that guy with you?

...<snipped>...

Dave


:funny:

#8 MooEy

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Posted 14 May 2013 - 08:27 PM

It depends on how short you want it to be...

http://www.sciencece.../borg/miniborg/

~MooEy~

#9 dennilfloss

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Posted 14 May 2013 - 09:13 PM

This one looks pretty short.

http://ca.skywatcher...ail.php?sid=417

#10 Derek Wong

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Posted 14 May 2013 - 10:06 PM

Other than Borg scopes, which can be super small aperture or break down into tiny parts, the Tak FCT-65 is about 11". If you adapt one for a Borg reducer (no tube cutting), it is 9.75", and if you cheat and remove the dewshield it is close to 6".

Derek

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#11 Mike Clemens

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Posted 14 May 2013 - 10:29 PM

JRBARNETT doesn't guide much, but when he does... it is with the Borg modified FCT-65

#12 Starhawk

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Posted 15 May 2013 - 12:14 AM

Well, this could be a trial scope to get started and see how this concept works for you without getting a lot of money tied up into it:

http://www.adorama.com/CNT50.html

If the experiment goes well, see if the Adorama guys can show you this:

http://www.adorama.com/BAAE11118.html

The thing to keep in mind is something like this next one shows a nice image, but again, it is bigger, and more expenive:

http://www.telescope...ec/apo110fl.htm

-Rich

#13 CounterWeight

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Posted 15 May 2013 - 07:01 AM

My FSQ-85 is pretty short, I haven't measured it but OPT site says it can collapse to ~12.6". The upper dovetail plate in the image is 7" long.

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#14 Scott99

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Posted 15 May 2013 - 09:36 AM

If we are spending $5K, don't forget the stubby TEC110 at 19"

#15 PhilCo126

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Posted 17 May 2013 - 12:15 PM

Why do You need a short Apo ? Travel or as guidescope :thinking:

#16 FishInPercolator

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Posted 17 May 2013 - 12:45 PM

I've been considering it for planetary and dso

#17 Scott Beith

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Posted 17 May 2013 - 04:44 PM

DSO - wide is good.
Planetary - you will need a short f/l EP to bump up the mags.

#18 Kon Dealer

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Posted 17 May 2013 - 05:27 PM

And there's me thinking that my Kson 102ED was short at 20.5" (retracted).

However the (carbon fibre) OTA only weighs 5.7lb. I reckon thatmust set some sort of record :shrug:

#19 MooEy

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Posted 17 May 2013 - 06:25 PM

Hmm...

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#20 FishInPercolator

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Posted 17 May 2013 - 06:37 PM

I would like the 2nd one from the left please, thank you.

#21 RAKing

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Posted 18 May 2013 - 06:55 AM

I would like the 2nd one from the left please, thank you.


That looks like the William Optics version of the ubiquitous carbon fiber 80mm triplet. If you want something like that, Orion has a nice one available:

Orion 80mm Triplet

FWIW, I owned the Astro-Tech model and it was a great scope! I used it on the Celestron NexStar mount. Very lightweight and very portable.

Cheers,

Ron

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#22 Kon Dealer

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Posted 18 May 2013 - 12:58 PM

Snap- I use my Kson 102mm on my SE mount.
Here it is at zenith :)

#23 Kon Dealer

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Posted 18 May 2013 - 12:59 PM

Rats! Didn't load again :foreheadslap:
Here's another go.

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#24 desertlens

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Posted 18 May 2013 - 02:42 PM

Forget much planetary but this is the shortest APO I've seen.

SV50 APO

#25 REC

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Posted 19 May 2013 - 08:12 AM

That looks like a nice set-up. Been thing about getting a small Goto for my 80mm. How do you like the performance?

Can you use the scope just in manual mode? I like to just point it at something sometimes.

Thanks,

Bob






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