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Advice on low power/locating EP for 5 inch DOB F/5


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Hi.

 

Can anyone recommend a 25 or 30mm EP to locate targets in my scope?  I was initially looking at BST 25mm but reviews have put me off. 

Was thinking of a Vixen NPL 30mm which would give a mag of 21x in my scope.

Also, are the Vixen ep's fine in my Focal ratio of F5 (i know some ep's struggle)

 

Thanks

 

 

Skywatcher 130P flexitube Dobsonian F/5

650 focal length

130mm aperture

Bortle 6

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6 minutes ago, Steve Clay said:

I have the Bst 25mm and also the vixen 25 and 30. You can't go wrong with any of them.

Steve

Thanks Steve.

First choice would have been BST 25mm but like i mentioned some people said the astigmatism is bad on fast scopes? I already have a BST 12mm but I was told the optics/build are slightly different between the 25mm BST and 12mm?

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The 25mm BST Starguider is not the best peformer of that range, I agree. I had one and it worked OK at F/7 but showed quite a bit of astigmatism in my F/5.3 dobsonian. The 30mm Vixen NPL is a nice eyepiece and sharper across more of the field of view - I liked the ones that I've owned:

 

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1 hour ago, wookie1965 said:

I've used my 25mm BST for over 3 years now to locate objects I've just got a GSO 32mm which after buying I've used about 4 times I still go for the 25mm.

But your scopes are F10 and F9.3.  As John said, the 25mm BST is not as good in faster scopes F5.

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1 hour ago, Colossal Plossl said:

But your scopes are F10 and F9.3.  As John said, the 25mm BST is not as good in faster scopes F5.

They are now only had them for a year had a Skywatcher 150p F5 and a Skywatcher 200p F5 and have always used the 25mm in fact the BST'S are very good in fast scopes. 

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I'm quite pleased with the ES 26 mmf/62° LER together with the 5.1" Heritage Flextube (giving a TFoV of 2.5°). Very clear, neutral coloured and sharp view, flat field, and a really relaxed, natural viewing, no "kidney beaning", or searching the correct eye position. No Edge-of-field brightening.The sharpness deteriorates from about 80% of the field diameter, somehow like an old fashioned Erfle, but that's not annoying, at least for me. Rather lightweight and cheaper, compared to it's rival, the highly praised ES 24mmf/68°. Lots of eye relief - no problem to use it with glasses.

There was a discussion on CloudyNights Sept. 2017 in the Eyepiece section

Stephan

Edited by Nyctimene
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I have a similar question about my f/4.7 Dobsonian.

What do people think about the Baader Hyperions or the ES 68 series and the Vixen SLVs? I suppose somebody will recommend Televue's but spending £2/300 on an eyepiece seems ridiculous. Diminishing returns and all that.

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Hyperions and F/4.7 don't mix well in my opinion. The ES 68 and Vixen SLV's are much better choices. Nivarna 82's are great value if you would like the wider field of view.

If you are fussy about edge correction and decide to use wide or ultra wide eyepieces you might also need to consider using a coma corrector to get the best out of them. That will correct much of the coma that the fast newtonian optics produce.

I won't talk about Tele Vue or Pentax :lipsrsealed:

Sorry that @wookie1965 and I disagree about the 25mm BST Starguider. I'm sure we are both calling it as we found it :smiley:

 

 

 

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5 minutes ago, John said:

Hyperions and F/4.7 don't mix well in my opinion. The ES 68 and Vixen SLV's are much better choices. Nivarna 82's are great value if you would like the wider field of view.

If you are fussy about edge correction and decide to use wide or ultra wide eyepieces you might also need to consider using a coma corrector to get the best out of them. That will correct much of the coma that the fast newtonian optics produce.

I won't talk about Tele Vue or Pentax :lipsrsealed:

Sorry that @wookie1965 and I disagree about the 25mm BST Starguider. I'm sure we are both calling it as we found it :smiley:

 

 

 

Thanks for that....very useful and will have a look at Nirvanas. I've seen elsewhere that Hyperions don't do well in a fast scope. Not especially fussy about edge correction but the proof's in the pudding and would consider a coma corrector if I found it an issue.

Thanks for not mentioning the unmentionable! 😃

  • Haha 1
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14 hours ago, John said:

Hyperions and F/4.7 don't mix well in my opinion. The ES 68 and Vixen SLV's are much better choices. Nivarna 82's are great value if you would like the wider field of view.

If you are fussy about edge correction and decide to use wide or ultra wide eyepieces you might also need to consider using a coma corrector to get the best out of them. That will correct much of the coma that the fast newtonian optics produce.

I won't talk about Tele Vue or Pentax :lipsrsealed:

Sorry that @wookie1965 and I disagree about the 25mm BST Starguider. I'm sure we are both calling it as we found it :smiley:

 

 

 

John I agree the 25mm is not the best of the bunch but it worked very well in all my scopes, for me the 15mm is the best I had the lot except the 3.2mm too powerful for my scopes. I have the 25,15 and 8mm left I sold the rest.

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