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Share your LONG-FOCUS ACHRO - Photos! Restart

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#1 Steve Fisher

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Posted 03 October 2009 - 05:04 PM

OK, I understand and I'm not going to be grumpy. It is time to restart this that was and will again become my favorite thread.

Looking forward to new pictures and posts.

My 6" f/12 D&G.

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#2 plyscope

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Posted 03 October 2009 - 05:15 PM

One of my favorite threads too Steve.

This is my 90mm f16.7 (Antares lens) and 6" f15 (D&G lens). Both use home made wooden tubes.

Here is a link to an article on how the tubes were made.
6 inch construction

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#3 Newfie Ninja

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Posted 03 October 2009 - 05:19 PM

All beautiful scopes but those wooden tubes are amazing!!

:bow: :bow: :bow:

Cheers

#4 Steve Fisher

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Posted 03 October 2009 - 05:20 PM

One of my favorite threads too Steve.

This is my 90mm f16.7 (Antares lens) and 6" f15 (D&G lens). Both use home made wooden tubes.

Here is a link to an article on how the tubes were made.
6 inch construction


Beautiful scopes and excellent wood work. I wish I had those kind of skills. Now days my skills seem to lean toward writing checks and opening boxes, but it works for me.

Thanks for posting.

#5 Bill Cowles

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Posted 03 October 2009 - 05:28 PM

Can you see anything? :smirk:

Bill

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#6 Shmals

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Posted 03 October 2009 - 06:29 PM

4" f/15

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#7 ngc2289

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Posted 03 October 2009 - 06:40 PM

Well my scope is only a 5" f/9.29 but I will post a picture anyway. :)

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#8 LivingNDixie

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Posted 03 October 2009 - 09:38 PM

Steve,

What is that strut hanging from the scope to the counterweight shaft?

#9 stevew

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Posted 03 October 2009 - 09:59 PM

OK lets get this straight.
What F-ratio is considered a long-focus achro?
I would not consider an F-8 as a long focus achromat.
In fact I would consider an F-8 a short focus achromat.

Steve

#10 mikey cee

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Posted 03 October 2009 - 10:25 PM

I would consider it to be f/13.3 at least! :smirk: :roflmao: :roflmao:Mike

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#11 Steve Fisher

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Posted 03 October 2009 - 10:30 PM

Steve,

What is that strut hanging from the scope to the counterweight shaft?


Preston:

It is a simple little accessory called a Hargreaves strut. It is a threaded rod, two turnbuckles and hardware to attach to the OTA and the shaft.

It cinches up just finger tight and removes a ton of wiggles and reduces dampening time immensely. The CGE is barely adequate for the length of this scope but it is more than stable enough for visual work with this strut.

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#12 Steve Fisher

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Posted 03 October 2009 - 10:37 PM

OK lets get this straight.
What F-ratio is considered a long-focus achro?
I would not consider an F-8 as a long focus achromat.
In fact I would consider an F-8 a short focus achromat.

Steve


I would think f/11 minimum. :grin:

#13 Steve Fisher

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Posted 03 October 2009 - 10:42 PM

I would consider it to be f/13.3 at least! :smirk: :roflmao: :roflmao:Mike



Mike:

What is your vote on the Hargreaves strut? Did you notice a huge difference?

#14 Bill Cowles

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Posted 03 October 2009 - 10:54 PM

Here is another image of Steve's D&G and the Hargreaves strut and yes it really works.

Bill

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#15 mikey cee

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Posted 03 October 2009 - 11:37 PM

Steve...My mount is so massive that it is really hard to tell. I haven't had enough time with the breezes to really tell yet. Maybe if my mount was less robust I could see more benefit. But it sure can't hurt and it definitely isn't a hindrance clearence wise. :smirk:Mike

#16 Steve Fisher

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Posted 03 October 2009 - 11:47 PM

Steve...My mount is so massive that it is really hard to tell. :smirk:Mike


Yes!, That is what I'm working on. :grin:

#17 Ziggy943

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Posted 04 October 2009 - 12:35 AM

Steve and his 6" F/12

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#18 Ziggy943

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Posted 04 October 2009 - 12:37 AM

My daughter's 6" F/17.5 (foreground) and Steve's F/12

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#19 Ziggy943

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Posted 04 October 2009 - 12:38 AM

Becky's 6" F/17.5

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#20 Ziggy943

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Posted 04 October 2009 - 12:39 AM

And in the sunset

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#21 Ziggy943

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Posted 04 October 2009 - 12:44 AM

OK lets get this straight.
What F-ratio is considered a long-focus achro?
I would not consider an F-8 as a long focus achromat.
In fact I would consider an F-8 a short focus achromat.

Steve


I would think f/11 minimum. :grin:


I'm going to split the difference and say F/12 for a 6"; F/15 for an 8" :) Take that Mike :)

#22 Trever

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Posted 04 October 2009 - 01:11 AM

I purchased the 102mm F/11 that was recently talked about from Stellarvue/Astrotelescopes. It is a very nice scope and well built. I will get a photo of it as soon as I can get it mounted to my mount.

#23 mikey cee

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Posted 04 October 2009 - 11:25 AM

Zigster....What I may questionably lack in one place I more than make up for it in another. 4-1/4" f/14.8! :pMike :roflmao: :roflmao:

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#24 Bill Cowles

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Posted 04 October 2009 - 12:36 PM

Don't forget Big Red, 8" F/16.3, I think.

Bill

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#25 Ziggy943

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Posted 04 October 2009 - 01:30 PM

Zigster....What I may questionably lack in one place I more than make up for it in another. 4-1/4" f/14.8! :pMike :roflmao: :roflmao:


Now we're talkin. Nice. :)


Bill, It's an F/16.7






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