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Favorite deep sky eyepiec focal length for C-9.25"

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#1 Lance1234

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Posted 13 September 2013 - 05:34 PM

For those of you with 9.25" SCTs (or anyone else with a scope with around a 2350mm focal length), what's your most used eyepiece focal length for deep sky? I realize this is a simplistic approach to a complex subject and the real answer is probably several focal lengths, but if there is one that seems to end up in the focuser most often, what is it?

#2 titanio

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Posted 13 September 2013 - 05:55 PM

Hello

For me the best the panoptics 35

Toni

#3 germana1

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Posted 13 September 2013 - 06:22 PM

My fav is the 27 pan or if seeing permits 13 Ethos.
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#4 Rick M.

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Posted 13 September 2013 - 07:07 PM

ES82 30mm or Ethos 13mm depending upon seeing.

#5 Lance1234

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Posted 13 September 2013 - 07:27 PM

In both your cases, that's a pretty huge jump from 27mm/30mm down to 13mm. What is the deciding factor?

#6 RTLR 12

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Posted 13 September 2013 - 07:37 PM

I have a C8 and my most used EP is my 17mm Ethos. I find that for most DSO targets I prefer the Mag and FOV of the 17. If I'm star hopping I'll use my 31 Nagler, but when I find something interesting I'll change to the 17 first and if seeing conditions and target allow maybe something with a bit more power.

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#7 mark379

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Posted 13 September 2013 - 08:57 PM

For deep sky widest field 31 Nagler.
For globs,etc. 11 or 14 ES 82...

#8 brianb11213

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Posted 14 September 2013 - 04:07 AM

For ANY scope, for deep sky objects, the one eyepiece I would not want to be without is one giving a reasonable field of view (60 deg is enough IMHO) with a 2mm exit pupil. For a f/10 SCT that's 20mm. I actually have several eyepieces with a focal length close to 20mm including a 20mm type 5 Nagler but the one that gets used most in my CPC1100 is a 20mm Meade "Super Plossl" (actually a 60 deg 5 element in 3 groups design) ... the reason being that the heavy 2" Nagler throws the tail-heavy scope even further out of balance. There is little difference the optical performance except that the Nagler has a noticeably wider appaernt field of view and a slight "warm" colour cast.

#9 Momerath

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Posted 14 September 2013 - 11:26 AM

i love my es14mm

#10 Stelios

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Posted 14 September 2013 - 12:41 PM

17mm Nagler. There's practically never a night when seeing affects it. And it's a perfect "window" into most objects.

The 13mm Nagler *can* be affected by seeing, and can't show as much. As for larger sizes (I have a 28mm UWAN and 40mm "cheapo") I find that I want more magnification, though all the mentioned eyepieces have their uses.

A 22mm Nagler might be ideal, but I don't have one (and don't really miss it). I have a *lot* of experience with the 9.25 which I've had for over 10 years, and 16-22 mm will be the "sweet" range for the viewing that 9.25 is good for (which is most anything *except* what calls for a wide field).

If I had to choose 3 EP's, it would be a 10, a 17 and something in the 28-35mm range. I probably would never need another.

#11 MrJones

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Posted 14 September 2013 - 01:46 PM

If I was going to pick a single EP it'd be the 24mm 68 degree Meade 5000. The current version of this is the ES 24mm and the Panoptic 24mm is very close also.

My most used at this point however is probably the 34mm 68 degree Meade 5000. It's good alone and with the f/6.3 focal reducer it gives a nice 1.6 deg TFOV at 43x.

I don't like the 82 degree as much as 68 degree.

#12 Brent Campbell

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Posted 14 September 2013 - 02:53 PM

On my C8 its my Meade SWA 40 MM! Cheap, maximum FOV, and suprisingly works very well in the C8.

#13 Lance1234

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Posted 14 September 2013 - 03:26 PM

For ANY scope, for deep sky objects, the one eyepiece I would not want to be without is one giving a reasonable field of view (60 deg is enough IMHO) with a 2mm exit pupil.

You're right about the 2mm exit pupil. From what I've read 2mm is supposed to be the optimum size for deep sky as you note. However, for whatever reason, I find that 20mm just doesn't give me as much magnification as I would like for many deep sky objects so that part is a quandary for me.

#14 mistyridge

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Posted 14 September 2013 - 11:45 PM

31mm Nagler.

#15 David Knisely

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Posted 15 September 2013 - 12:35 AM

For those of you with 9.25" SCTs (or anyone else with a scope with around a 2350mm focal length), what's your most used eyepiece focal length for deep sky? I realize this is a simplistic approach to a complex subject and the real answer is probably several focal lengths, but if there is one that seems to end up in the focuser most often, what is it?


My two favorites are my 40 mm MK-70 Konig (59x, 1.12 degree TFOV), and my 14mm ES-100 eyepiece (169x, 35.5 arc minute TFOV). Clear skies to you.

#16 dragonslayer1

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Posted 15 September 2013 - 09:17 AM

I just use video cam now but when I did view I really likes the Explore Scientific. Very good E/P and good price,
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#17 iluxo

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Posted 15 September 2013 - 09:34 PM

In my f/15 Mak (2700 mm fl) my favourite eyepieces are a Vixen 50mm LV, and 13mm LVW. In your SCT these would be similarly effective, with a brighter image.

#18 McUH

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Posted 16 September 2013 - 02:59 PM

If only one, I agree something in 16-24mm range, at least 68° FOV. But only as a compromise, I do not agree on some "2mm exit pupil magic". Every DSO has its own requirements.

For dim nebula or extended cluster 40mm-60mm for bright image and large FOV.
Around 20mm good for many Messiers, large (but not huge) clusters, galaxies.
Around 11mm or even less for weaker globulars (or to really resolve M13), compact clusters, planetary nebulae etc.

#19 WesC

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Posted 16 September 2013 - 05:02 PM

31mm Nagler/30mm ES82, 20mm ES100, 11mm Nagler T6. I'm considering adding either a 13mm Ethos or a 14mm ES100.

This is with my Edge 11, but they should work great with the 9.25 as well.

#20 Dave Lee

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Posted 16 September 2013 - 05:39 PM

For me the most used EP is an old Meade 56mm plossl (1990's incarnation of a C11). It gives me the biggest FOV available in a 2 inch format, and works well when 'finding stuff' (I am a star hopper).

For actual observing I find that my ES 18mm (82* FOV) is the most frequently used followed by a UO 32mm Erfle and occasionally a ES 14mm (and rarely an old 9.7mm Plossl).

One nice thing about f10 scopes is that less expensive EP's work reasonably well.

dave

#21 hfjacinto

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Posted 16 September 2013 - 07:43 PM

I have a 9.25 and I use the following eyepieces pretty much every time I'm out.

31 MM Nagler - great for large open clusters and large diffuse nebula.
20 MM ES 100° - used as a finder and for the smaller open clusters. I pretty much start with the 20 and go up and down for the object.
14 MM ES 100° - best for smaller clusters and globules
9 MM ES 100° - my starting planet ep, also a planetary nebula go to eyepiece.

If seeing is good I may go to the 6.7 MM Meade UWA or the 6 MM Radian. Depends on seeing and the object.

#22 ensign

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Posted 17 September 2013 - 11:31 AM

I have a 9.25 Edge also with FL=2350.

The 22 Nagler Type 4 is pretty much the workhorse, but as others have mentioned, it depends on the object.

For wider fields (if you can call 1.1* wide) the Pentax 40XL is the weapon of choice. For detail in globulars, the Delos 14 is ideal (you still get pinpoint stars even with average seeing). I also enjoy the view of many objects through the Pentax 30 and the 17mm Nagler.

So the lineup of 40XL, 30XW, 22 T4, 17 T4 and 14 Delos is what I use on a typical night.

#23 Lance1234

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Posted 18 September 2013 - 03:11 PM

I really appreciate everyone's input; it has been very helpful. As a quick synopsis, the 13-14mm range seems to get the most use with the Ethos 13 & ES 14/100 being the most popular. These were followed by the Nagler 31 and a couple of other eyepieces in the 30-35mm range. The Ethos 17mm & a couple of eyepieces in the 40mm range were also popular. All in all great help in developing a selection of eyepieces.






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