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Zhumell 32mm Widefield

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#1 sopticals

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Posted 16 December 2018 - 07:04 PM

Anyone know about these? Quality, FOV? I have acquired one with the purchase of my 10" Zhumell dob.

 

Stephen.(45deg.S.)



#2 ShaulaB

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Posted 16 December 2018 - 07:06 PM

Use it and see how you like it.


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#3 Augustus

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Posted 16 December 2018 - 07:22 PM

It's an Erfle. Works moderately well above f/5, disaster at fast focal ratios. Lots of edge of field astig.


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#4 dtsh

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Posted 16 December 2018 - 07:25 PM

I had one, recently sold it. It's an inexpensive eyepiece so it makes some tradeoffs in performance. In my F/4.9 reflector it was not good; even sadder that it *came with* said scope. scratchhead2.gif

 

If you can get it for free, or nearly so, and you've got something F/6 or slower, it might work decent.

 

 

After zxx's post below I realized mine was also a 30mm, so kindly disregard.


Edited by dtsh, 16 December 2018 - 08:46 PM.

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#5 Jon Isaacs

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Posted 16 December 2018 - 07:25 PM

Stephen:

 

The field of view is around 60-65 degrees.  They're some sort of a Erfle (or maybe Konig ) derivative .

 

I see you have a 31 mm Nagler.  The Zhumell 30 mm will remind you just how good the 31 mm is. 

 

Jon


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#6 Jon Isaacs

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Posted 16 December 2018 - 07:50 PM

. In my F/4.9 reflector it was not good; even sadder that it *came with* said scope.

It's an entry level eyepiece included with scopes that cost $400-$800 and require star hopping .

 

It has to be cheap to avoid raising the cost of the scope but it also has to be an effective eyepiece for star hopping and low power viewing.  It's an eyepiece a first time scope owner should enjoy and find useful. Off-axis astigmatism is something the experienced eye sees . A first timer ought to be thrilled with the view .

 

It's significantly better than a 25 mm Plossl or the three element 28mm DeepView Orion provides as their entry level 2 inch Dob eyepiece .

 

I think it's a smart choice. 

 

Jon

 

 

 

 

 

I t


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#7 zxx

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Posted 16 December 2018 - 08:16 PM

A 2" 30mm came with my Z12 ,its a well made eyepiece by GSO . gives a nice view for a cheep eyepiece .

I believe the 32mm by GSO is a 1.25"


Edited by zxx, 16 December 2018 - 08:32 PM.


#8 sopticals

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Posted 16 December 2018 - 08:49 PM

 

I believe the 32mm by GSO is a 1.25"

This one is 2". I will probably "just move it on". Was thinking of using it with my 120mm f8.3 refractor for a 1.9 deg FOV (31.25x), but will use instead 31 Nagler for FOV 2.54 deg FOV @ 32x

and 20NT2 for 50x and 1.6 deg FOV.

 

Stephen.(45deg.S.)


Edited by sopticals, 17 December 2018 - 01:24 AM.

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#9 CeleNoptic

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Posted 17 December 2018 - 11:08 PM

 

The field of view is around 60-65 degrees. 

 

Nope. I also suspected that. But to my surprise the timing test showed it was exactly 68* as claimed.


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