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Not enough back focus on Denk Standard with C11

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#1 shkong

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Posted 20 August 2013 - 07:42 PM

I had 5 consecutive cloudy days at my home in Northern Washington State.

Last night, I tried out Denk Standard with C11 and it did not have enough focus.

What was wrong?

Denk Standard worked fine with C8.

Is there something wrong with 2 inch diagonal?

I may have to swap the 2 inch diagonals that I am using with C8 and C11.

Anybody can give me advice?

Thanks

Thomas

:help:

#2 Eddgie

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Posted 20 August 2013 - 09:39 PM

Have you checked to make sure that you don't have a screw sticking into the path of the mirror keeping it from moving forward?

I know that many people report great results with the Denks on a C11, so there may be some mechanical issue???

#3 T1R2

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Posted 21 August 2013 - 03:40 AM

I have the Big Easy, and had no probs after finding out that if you have a 6.3FR on the back of the scope you can't also have the one that comes with the BV as well, one or the other, hopefully your not doing this either, its a mistake that a lot have made...I think :foreheadslap:

#4 shkong

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Posted 21 August 2013 - 06:29 PM

Somehow I have a barely enough back focus on Denk Standard with Televue 76 with 2 inch diagonal.

Let me find out whether 2 inch diagonal take too much focus or not.

Thanks Edgie and T1R2 for the opinion.

Thomas

#5 Sorny

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Posted 21 August 2013 - 07:46 PM

I had 5 consecutive cloudy days at my home in Northern Washington State.

Last night, I tried out Denk Standard with C11 and it did not have enough focus.

What was wrong?

Denk Standard worked fine with C8.

Is there something wrong with 2 inch diagonal?

I may have to swap the 2 inch diagonals that I am using with C8 and C11.

Anybody can give me advice?

Thanks

Thomas

:help:


Something odd is going on. The C11 should be more than capable of focusing with a Denk. I'm assuming you're using a normal 2" visual back, refractor style 2" diagonal (or SCT style 2" diagonal), and Denk binoviewer body only with 2" nose into the diagonal, right? No extender tube or OCS like you'd use on a Newt? I can't think of a single reason that setup will not work unless your focuser has issues, or you've got screws impeding mirror travel. A C11 is very tolerant of goodies hooked up off the back of the scope, and has a huge focus range.

#6 shkong

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Posted 22 August 2013 - 02:54 AM

Sorny

I agree with you something is odd.

But clear tonight, I am concentrating on AP not binoviewing.

I will find out why later.






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