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what 30mm to 50mm class eyepiece are you using with your SCT/ACF/Edge ?

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#51 makeitso

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Posted 20 September 2019 - 04:45 PM

Jack:

 

No surprise there, the C-6 has the same 1 inch rear port as the C-5 so with the reducer, the effective diameter of the port is about 16mm.. 

 

Did you try the 35mm Pan on the C-6 without the reducer?

 

I should add that Glenn LeDrew has experienced this and has a good explanation.. 

 

Jon

I tried without the reducer and it was much better. I don’t remember it being bad at all so it had to be minimal. I see no noticeable vignetting with my ES24-68.

 

Jack


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#52 Jon Isaacs

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Posted 20 September 2019 - 05:34 PM

Well I'm sure what Jon is saying correct is to the extent that the baffle tube will offer a soft field stop without a hard edge because it is not close enough to the plane of focus. But where would the any other wider rays come from outside the light cone that passed the end of baffle tube? I think this is demonstrable using a laser and seeing where the baffle tube cutoff point is.  

 

As I said, a camera would see it..  there's no doubt there would be real vignetting.

 

But seeing it with the eye, what I see looking through the eyepiece... it's very counter intuitive. 

 

My own pet theory to explain it is that the eye doesn't not have a uniform number of rods distributed across the retina nor are they uniformly illuminated.  There's probably some processing going on that balances the illumination and it just natural includes gentle external vignetting.

 

Jon



#53 Daniel Mounsey

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Posted 20 September 2019 - 06:33 PM

I tried without the reducer and it was much better. I don’t remember it being bad at all so it had to be minimal. I see no noticeable vignetting with my ES24-68.

 

Jack

 

If it makes you feel any better I only use 1.25" eyepieces on my classic C8 with a 6.3 reducer. For planets I remove the reducer because it adds a slight amount of spherical aberration. C6. just use a 6.3 reducer and just use 1.25" eyepieces. That's still plenty wide. For widefield I use my refractors and binoculars. 


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#54 makeitso

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Posted 20 September 2019 - 08:28 PM

I only have 1.25 eyepieces. The biggest of which is the ES24-68 so that’s not a problem. I only have 1.25 filters too. If I use the C6 to view planets definitely take the reducer out since I want less glass and more magnification. 

 

I just thought id see what happened when I did it, not good results.

 

Jack



#55 25585

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Posted 21 September 2019 - 01:10 AM

The 30XW and 40XW are expected back out by December.

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#56 25585

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Posted 21 September 2019 - 01:16 AM

I have a question, do many people use the Celestron 0.63x reducer/corrector visually? 

 

I know that it effectively reducers the focal length of the scope but what does it "correct?"

 

If so what have you noticed about the outer 1/3 of the field with widefield eyepieces vs narrower AFOVs like Orthos and Plossls? 

 

Where does vignetting start in terms of AFOV and eyepiece focal length on which scopes 8" 9.25" 10" 11" 12" 14"? 

It also has a more practical purpose, keeping the OTA's inside protected and clean.



#57 Brent Campbell

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Posted 22 September 2019 - 09:24 AM

I use a 40mm Mead Swa 68 degree for my wide field that I purchase for $125 when Meade was blowing them out. I use it primarily as my finder eyepiece and it doesn’t stay in the diagonal for long.  I once owned a denkmeier switch diagonal but sold it because the number of mechanical connections that it had was ridicules.  I don’t want a reducer corrector because of the effort to unscrew it when you want higher powers.  

 

I see see allot of individuals recommended  the 35 pan.  Ergonomically the 35 pan is half the weight of my mead 40mm swa.  Has anyone compared the Meade 40 mm swa to the Pan 35? Was is enough of an improvement to justify the additional cost?



#58 25585

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Posted 22 September 2019 - 09:55 AM

I use a 40mm Mead Swa 68 degree for my wide field that I purchase for $125 when Meade was blowing them out. I use it primarily as my finder eyepiece and it doesn’t stay in the diagonal for long.  I once owned a denkmeier switch diagonal but sold it because the number of mechanical connections that it had was ridicules.  I don’t want a reducer corrector because of the effort to unscrew it when you want higher powers.  

 

I see see allot of individuals recommended  the 35 pan.  Ergonomically the 35 pan is half the weight of my mead 40mm swa.  Has anyone compared the Meade 40 mm swa to the Pan 35? Was is enough of an improvement to justify the additional cost?

The SWA or ES Maxvision 34mm, is a good eyepiece, less heavy than the 40mm. Or an ES68 34mm, same optics but more expensive, though much less than a Pan.

 

The SWA/MV eyepieces can be decloaked to reduce their weight.


Edited by 25585, 22 September 2019 - 09:55 AM.



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