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Visual Paracorr not optimized for 31T5 - what does this mean exactly?

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#1 thecelloronin

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Posted 27 February 2021 - 01:14 AM

Over and over I’ve read veterans in the know caution that the 31T5 Nagler doesn’t have an optimal setting in the Visual Paracorr (type 1). But what are the performance implications of this? What would I see, relative to what I’d see in the optimized setting of the Paracorr Type 2? And what’s this about vignetting in the T2? Is it just impossible to win with the 31T5? Logic says no, since an awful lot of folks find it to be a winning combination...

#2 CHASLX200

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Posted 27 February 2021 - 06:38 AM

My 31mm Nagler worked fine in my first Gen Paracorr. Never tried one in my type 2 Paracorr.



#3 scotsman328i

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Posted 27 February 2021 - 06:43 AM

https://www.cloudyni...-31t5-and-22t4/



#4 Jon Isaacs

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Posted 27 February 2021 - 07:19 AM

Over and over I’ve read veterans in the know caution that the 31T5 Nagler doesn’t have an optimal setting in the Visual Paracorr (type 1). But what are the performance implications of this? What would I see, relative to what I’d see in the optimized setting of the Paracorr Type 2? And what’s this about vignetting in the T2? Is it just impossible to win with the 31T5? Logic says no, since an awful lot of folks find it to be a winning combination...

 

I have a 31mm Nagler and have used it in both a Paracorr like yours and the Paracorr 2. 

 

Back when there was no Paracorr 2, no one worried about the fact that Paracorr 1 didn't have quite enough inward travel, it works very nicely, there may be some residual coma, at F/5 you'll never see it.

 

When I got the Paracorr 2, I noticed a slight vignetting at the very edge of the field with the 31mm Nagler.  I had not seen mention of it on Cloudy Nights so I called up TeleVue and ended up talking with Paul Dellechiaie, the designer.  He said, yes, if you looked carefully, you would see slight vignetting at the very edge of the field with the 31mm Nagler.  Now, it's there but I don't see it.

 

They both provide amazing views with the 31mm Nalger.

 

jon


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#5 MitchAlsup

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Posted 27 February 2021 - 12:12 PM

One can consider that the 31NT5 is not optimal in a Paracorr-1 because P-1 was designed and manufactured before the 31NT5 was a gleam in Al Nagler's eye.

 

That does not mean you don't get wide sharp vistas, its just you could have gotten a "tad more".



#6 thecelloronin

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Posted 27 February 2021 - 07:41 PM

Thanks for the good words everyone.




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