
Need advice on eye piece for high power
Started by
Guest_**DONOTDELETE**_*
, Jun 20 2004 03:21 PM
11 replies to this topic
#1
Guest_**DONOTDELETE**_*
Posted 20 June 2004 - 03:21 PM
Im using a 10" LX200 and I am looking for a high power eye piece, I am looking at the Pentax 7mm WX mainly because of the eye relief, any advice or suggestions would be most appreciated, my current collection contains 2 eye pieces a Tele Vue 31mm Nagler and a Meade 14mm Ultra Wide and I am very happy with these two, does anybody like the high power zooms??
Thanks
Ray K
Thanks
Ray K
#2
Posted 20 June 2004 - 04:22 PM
I like the Nagler zooms, but they aren't for 10" f/10 scopes like yours. Do you currently use the 14mm Ultrawide with a 2x Barlow? The reason I ask is that the magnification seems a little high for most locales. About the shortest focal length that I would recommend for your scope anywhere without great planetary seeing on a regular basis is 9mm or so. How about a 10mm Pentax XW?
#3
Guest_**DONOTDELETE**_*
Posted 20 June 2004 - 07:43 PM
Mike I currently have a Tele Vue 2x Barlow (1.25) and about the 10mm Pentax XW I am now going to go into study mode, the 10mm Pentax was on the back of my mind and I will take your advice and study it.
Thanks Mike
Ray K
Toronto
Thanks Mike
Ray K
Toronto
#4
Posted 20 June 2004 - 11:50 PM
I agree with Mike, I owned a LX200 10 for 3 or 4 yrs and the highest effective mag I was able to use was 10mm. I used a 10mm radian which have a generous 20mm ER. On a rare occasion I used my 7mm Seibert on planets. my 13 nag T6 and Meade 12.4 Plossel got the most use for trying to push it. My skies are about mag 5.5 .
#5
Posted 21 June 2004 - 02:14 AM
I'm very happy of the way my Radians perform on the SCTs I've used them with. However, a guy I purchased two of them from said he was selling them because he was sticking to his 3-6mm zoom so it must be an excellent eyepiece. A 3-6 zoom might be too much power for a 10" f/10 though. And I've seen mixed reports (read: not very good) about the 8-24 types of zooms.
On my 8" the highest power I've used was 400x with a 5mm Radian, and I could only use that power twice (exceptional conditions only). "Very good night" is when I can use the 6mm (333x) "good night" is 250x with the 8mm. I use the 12mm (160x) on all but the worst nights.
On my 8" the highest power I've used was 400x with a 5mm Radian, and I could only use that power twice (exceptional conditions only). "Very good night" is when I can use the 6mm (333x) "good night" is 250x with the 8mm. I use the 12mm (160x) on all but the worst nights.
#6
Posted 21 June 2004 - 09:43 AM
Ray,
If you like the Meade 14UWA, how about the Meade 8.8UWA. These are the 2 most used eyepieces on my SCT.
Don
If you like the Meade 14UWA, how about the Meade 8.8UWA. These are the 2 most used eyepieces on my SCT.
Don
#7
Guest_**DONOTDELETE**_*
Posted 22 June 2004 - 01:46 PM
I also do own a Meade 10" LX200. But use only so now and then my 7mm LV Vixen for high (planetary) powers. It is seldom useful so the ep is seldom used.
The seeing is mostly the limiting factor for such high powers on the LX. For my Sky 90 I have a Nagler zoom 3-6mm. Off cause I have tried it out once on the LX, but forget it!!
I think a good 7mm Ep is as high as you can go for Ep's without using barlo.
You also can consider the use of the TV powermates pending on the ep's you already got.
Bonzo
The seeing is mostly the limiting factor for such high powers on the LX. For my Sky 90 I have a Nagler zoom 3-6mm. Off cause I have tried it out once on the LX, but forget it!!

I think a good 7mm Ep is as high as you can go for Ep's without using barlo.
You also can consider the use of the TV powermates pending on the ep's you already got.

Bonzo
#8
Guest_**DONOTDELETE**_*
Posted 23 June 2004 - 11:06 AM
If you don't mind the narrow field (especially so in a f/10 SCT), go for an UO Ortho or, if you can afford it, a TMB Monocentric. I've only looked through the ortho (and enjoyed it), but reviews claim that the monocentric is also great.
If you do mind the narrow FOV, an 8- or 14mm Meade UWA should be pretty good. I also like the 4.8mm Nagler.
If you do mind the narrow FOV, an 8- or 14mm Meade UWA should be pretty good. I also like the 4.8mm Nagler.
#9
Guest_**DONOTDELETE**_*
Posted 23 June 2004 - 02:52 PM
I personally think a 4,8mm Nagler is too much for an 10" f10 and it seldom will be used, although it is a remarkable eyepiece. If it has to be a short focal Nagler I would go for the 7mm as a minimal focal length.
Bonzo
Bonzo
#10
Guest_**DONOTDELETE**_*
Posted 24 June 2004 - 07:58 AM
I can't say, I haven't used the 7mm. I certainly liked the views with the 4.8 though, even with a f/9 refractor. In the 10" f/10, the TFOV should be 82/525=0.15-deg. I overestimated the Nagler's AFOV (it's 82, right?). It certainly beats a 5mm Monocentric though
(0.06-deg).

#11
Guest_**DONOTDELETE**_*
Posted 24 June 2004 - 10:16 AM
Well, it is not so much the FOV that concerns me; it's more the magnification factor!
On a focal length of 2500mm the 4.8mm produces 530x magnification. I think this is well overdone. Even with the 7mm in place the magnification will be 365x. Such high magnifications are seldom usable! I think you are better off with a 9mm eyepiece, which will be more often used.
Bonzo
On a focal length of 2500mm the 4.8mm produces 530x magnification. I think this is well overdone. Even with the 7mm in place the magnification will be 365x. Such high magnifications are seldom usable! I think you are better off with a 9mm eyepiece, which will be more often used.
Bonzo
#12
Posted 24 June 2004 - 01:45 PM
I agree with the posts above stating those short eyepieces produce way too much magnification.
The 8.8 Meade Ultrawide would be a beautiful chunck of glass to drop into a 10" f/10. It would give about 285x, possible useful fairly often, although getting up there. Eye relif is short, but it's still comfortable to use.
edz
The 8.8 Meade Ultrawide would be a beautiful chunck of glass to drop into a 10" f/10. It would give about 285x, possible useful fairly often, although getting up there. Eye relif is short, but it's still comfortable to use.
edz