Favorite deep sky eyepiec focal length for C-9.25"
Posted 13 September 2013 - 05:34 PM
Posted 13 September 2013 - 06:22 PM
Posted 13 September 2013 - 07:27 PM
Posted 13 September 2013 - 07:37 PM
Posted 13 September 2013 - 08:57 PM
For globs,etc. 11 or 14 ES 82...
Posted 14 September 2013 - 04:07 AM
Posted 14 September 2013 - 12:41 PM
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.
Posted 14 September 2013 - 01:46 PM
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.
Posted 14 September 2013 - 02:53 PM
Posted 14 September 2013 - 03:26 PM
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.
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.
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.
Posted 15 September 2013 - 09:17 AM
Posted 15 September 2013 - 09:34 PM
Posted 16 September 2013 - 02:59 PM
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.
Posted 16 September 2013 - 05:02 PM
This is with my Edge 11, but they should work great with the 9.25 as well.
Posted 16 September 2013 - 05:39 PM
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.
Posted 16 September 2013 - 07:43 PM
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.
Posted 17 September 2013 - 11:31 AM
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.
Posted 18 September 2013 - 03:11 PM