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9mm EP with good quality, eye relief for fast scope?

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#1 Orion92

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Posted 17 August 2014 - 01:36 PM

Hi everyone,

 

Yet again I ask another EP question to the gurus! I currently have a 34mm EP (45x) and a 14mm (114x) for my 12.5" f/5 1590mm FL Dob that I am getting in about a month. I figured between an 8mm and a 9mm EP, the 9 would be a better jump in power over an 8mm. It appears that neither Pentax or Televue offer a 9mm EP with good eye-relief. Do any other manufacturers have a 9mm with the specs I am looking for? What might you recommend to me?

 

Thank you all,

 

Kyle



#2 csrlice12

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Posted 17 August 2014 - 02:53 PM

If plossl like fov is no problem, theres the Vixen LV (or NLV or SLV) which have 20mm eye relief.  These are all the same eyepiece with updated body styles.  Don't know why Vixen did this, but they did.  Excellent eyepieces too....



#3 Damo636

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Posted 17 August 2014 - 03:44 PM

The Pentax 8.5mm XF would be another excellent choice, sharp as a tack with a nice 60° afov & comfortable eye relief.


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#4 Scanning4Comets

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Posted 17 August 2014 - 04:11 PM

If I were you, I'd skip the 9mm size and get a 10mm Pentax XW or 10mm TeleVue Delos which have 70-72 degree AFOV and nice long eye relief.

 

Both do not need a coma corrector as they are super sharp across the entire field in a fast scope.

 

Cheers,


Edited by Scanning4Comets, 17 August 2014 - 04:12 PM.


#5 Orion92

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Posted 17 August 2014 - 04:23 PM

If I were you, I'd skip the 9mm size and get a 10mm Pentax XW or 10mm TeleVue Delos which have 70-72 degree AFOV and nice long eye relief.

 

 

A 10mm would give me ~160x mag, do you think there is enough bang for the buck if I choose one of those two eyepieces? I would be going from 114x to 160x between a 14mm and a 10mm.



#6 BDS316

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Posted 17 August 2014 - 04:34 PM

The Pentax 8.5mm XF would be another excellent choice, sharp as a tack with a nice 60° afov & comfortable eye relief.

:waytogo:



#7 Scanning4Comets

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Posted 17 August 2014 - 04:46 PM

 

If I were you, I'd skip the 9mm size and get a 10mm Pentax XW or 10mm TeleVue Delos which have 70-72 degree AFOV and nice long eye relief.

 

 

A 10mm would give me ~160x mag, do you think there is enough bang for the buck if I choose one of those two eyepieces? I would be going from 114x to 160x between a 14mm and a 10mm.

 

 

I go from 100x to 150x, (12mm Delos to an 8mm Delos), so they are close, but if you want more of a spread in mag, you could get an 8mm Delos for 199x.



#8 izar187

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Posted 17 August 2014 - 05:53 PM

200x is a very nice magnification range to have for this size scope.

Well, for many other scopes too.

But this range, with large well corrected field, and long eye relief... it's the bees' knees.

 

Shop used when possible, and/or pool funds for as many weeks as needed. 



#9 jack45

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Posted 17 August 2014 - 06:24 PM

The 8.5mm SMC Pentax XF, excellent ER and viewing EP.

 

Clear Skies! 



#10 CeleNoptic

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Posted 17 August 2014 - 10:29 PM

IMO, it's better using eye pupil rather than magnification because eye pupil determines brightness of the image and magnification is  a dependent aspect. The step of 1.4x between 14 and 10mm isn't too small, IMO.

Actually, three eyepieces, that give you eye pupil of 1mm, 2mm and 3-4mm (focal lengths 5mm, 10mm and 15-20mm) will cover most of your needs. You've got one of them (14mm - 2.8mm eye pupil), so you just need two. And I like Mark's suggestion on Pentax XW or Delos. You may need the 10mm and 5mm XWs or maybe even better the 10mm and 6mm Delos, because the 5mm XW can be too much for most of the nights. And if you have a good 2x telecentric Barlow like ES Focal Extender or TV Powermate you can get two additional eyepieces, 7mm and 5mm, by barlowing your 14mm and *future* 10mm.

 

As for Pentax XF...well, eyepieces are a kind of subjective AFOV included...I was on the fence a couple of months ago trying to decide between the 8.5mm XF and the 8.8mm Meade UWA...and I decided on the latter. I already have the 14mm UWA and after looking through the 82*AFOV I just can't appreciate the 60*AFOV, especially when observing open clusters. My minimum for DSOs is 65*AFOV and I wouldn't want anything narrower than  Pentax XL. But it's just me, YMMV.


Edited by CeleNoptic, 17 August 2014 - 10:32 PM.


#11 bgi

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Posted 18 August 2014 - 09:49 AM

Agreed on the Delos suggestion.  I'm evaluating some Delos and XWs.  So far, I'm liking the Delos more.  Recommend the 10mm Delos or XW and then get a good 2x barlow (Televue is excellent) to double your set.



#12 coutleef

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Posted 18 August 2014 - 10:59 AM

i have a scope similar to yours and am very satisfied using a 14 with a 10mm ep without a need for something in between






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