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ES 20 mm 100* + Paracorr 1

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#1 acochran

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Posted 17 October 2013 - 12:27 AM

I think my ES 20 mm 100 degree 2 inch eyepiece hits the Paracorr 1 lens at setting 5. Anybody else? Recommendations?
Maybe add a 2 inch O-ring to the eyepiece?
Andy

#2 csrlice12

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Posted 17 October 2013 - 07:00 AM

Hadn't noticed it in mine, but it was dark out! I'll have to check this out later, but I didn't notice anything unusual when I used it. The 14mm worked fine. I have the older PC2001 version with the tuneable top.

#3 star drop

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Posted 17 October 2013 - 10:31 AM

At setting 5 the Paracorr lens is two inches from the top. My 20mm ES100° has a one and a half inch insertion leaving one half inch of clearance. If one has been viewing using an eyepiece that requires a lower setting something interesting happens. Placing the 20mm ES into the Paracorr and then changing the setting to 5 results in the compression of air between the Paracorr top lens and the ES field lens. Is that what you are noticing? The solution is to set the Paracorr before inserting the eyepiece.

#4 SteveG

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Posted 17 October 2013 - 01:10 PM

At setting 5 the Paracorr lens is two inches from the top. My 20mm ES100° has a one and a half inch insertion leaving one half inch of clearance. If one has been viewing using an eyepiece that requires a lower setting something interesting happens. Placing the 20mm ES into the Paracorr and then changing the setting to 5 results in the compression of air between the Paracorr top lens and the ES field lens. Is that what you are noticing? The solution is to set the Paracorr before inserting the eyepiece.


Wow - I've never experienced that! Mine is certainly not air-tight, and I always tune (focus) the Paracorr with the EP in place.

#5 csrlice12

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Posted 17 October 2013 - 01:59 PM

My glatter laser does that in a Tublug, but my paracorr doesn't...

#6 Starman1

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Posted 17 October 2013 - 04:11 PM

I think my ES 20 mm 100 degree 2 inch eyepiece hits the Paracorr 1 lens at setting 5. Anybody else? Recommendations?
Maybe add a 2 inch O-ring to the eyepiece?
Andy

First, I believe there is a stop in the Paracorr to prevent the eyepiece barrel from hitting the lens of the Paracorr.
Second, I don't believe the slightly convex Paracorr lens sticks up enough to hit the convex bottom lens in the 20mm ES eyepiece, though they won't be far apart.
Third, I believe it's possible the lowest setting (5) is merely the best you can do, IIRC, the "correct" setting would be even closer, though, of course, neither the Paracorr nor eyepiece allows that.

I do remember that the 21mm Ethos hit that stop before the upper barrel of the eyepiece actually contacted the Paracorr's tunable top, i.e. when fully inserted, I could actually raise the tunable top a trace before it hit the eyepiece "shoulder". But the lenses never touched. And the 20mm ES is, I think, almost identical to the 21 Ethos in that regard.






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