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randb
2006-Mar-09, 10:50 PM
I have a C9.25 (recently acquired), for which I'm planning on buying some high quality eyepieces. I just bought one of those UHTC 2" SCT diagonals. I was thinking of getting the Meade series 5000 super plossl set. (5.5, 14, 20, 32 mm for $350) Anyone ever used these before? What do you guys suggest. I wanna get the entire Nagler set, but can't afford those now. Any suggestions?

aurora
2006-Mar-09, 11:37 PM
I don't think there is any particular reason why you need an entire set of eyepieces, unless you are an eyepiece collector or you think they are really cool.

Having a few really good eyepieces is much better than having many mediocre ones. Not saying the Meade's are mediocre, just some general advice which depends on your budget.

Plossls are good eyepieces, but in the shorter focal lengths, especially down around 10mm or shorter, the eye relief tends to get really small. So small that I find it uncomfortable to use them even if I am not wearing glasses.

What you might need, since you have a 2 inch diagonal, is one really good quality low power 2 inch eyepiece, and then a medium and a high power one, probably in the 1.25 inch size.

The really high power eyepieces will be used only on rare occasions, if your seeing is typical where you live.

naios
2006-Mar-10, 12:12 AM
You might want to take a look at the Meade 4000 QX series. Decent quality and the price is pretty good. I own the 15 (1.25) and 26 mm (2) and really, really enjoy them. They are 70' apparent field of view. Of course, I've never had the opportunity to look through a Nagler...

Also, do you own a Barlow?

randb
2006-Mar-10, 12:28 AM
You might want to take a look at the Meade 4000 QX series. Decent quality and the price is pretty good. I own the 15 (1.25) and 26 mm (2) and really, really enjoy them. They are 70' apparent field of view. Of course, I've never had the opportunity to look through a Nagler...

Also, do you own a Barlow?

I have a celestron 1.25" 2x barlow, but I want to get the Meade APO barlow. I heard good things about it.

randb
2006-Mar-10, 12:29 AM
Has anyone tried any of the William Optics SWANs and UWANs?

ottUp
2006-Mar-10, 01:50 AM
I have a C9.25. Remember it's a pretty long focal-length scope (2350 mm).

My most-used eyepieces are Nagler 22, 17, and 11s, and an 8mm Radian.
22 Probably the most - magnificent wide fields at about 100x. 17 for a bit more power. The 11 and 8 get the magnification into the 200-300x range which are great for Saturn and Jupiter. Below 11mm I like Radians more than Naglers, for the constant and generous eye relief.

The 5.5 in the set you mentioned is at the theoretical magnification limit for this scope, giving around 425x, which is too much for just about any observing conditions unless you live on a mountain. So I'd say you'd rarely or never use the 5.5.

I would echo the other advice, 2 or 3 excellent eyepieces will make you happier than a larger number of moderate quality ones. I'd say there's no reason to buy a set all at once, and a good reason not to: buy one at a time, each time after you have tried the eyepiece in question at a star party or by borrowing from a friend.

If I could only have one eyepiece for my 9.25 it would probably be the 17. If I could have two it would be the 22 and the 11. If I could have 3, the 22, a 2x barlow, and the 17 (giving me 22, 17, 11, and 8).

(The actual collection is 31, 22, 17, 12, 11 naglers, & 10, 8, 6, 4, 3 Radians. (That's for more than just the C9.25 OTA)).

Regards
Richard

Dave Mitsky
2006-Mar-10, 06:39 AM
Since you have a slow f/10 scope, a well-corrected-for-astigmatism design such as the Tele Vue Nagler is not strictly necessary. You'll be giving up the ultrawide 80 degree plus apparent field of view of the Nagler and Meade UWA designs (I have heard from more than one source that the old Japanese UWA versions are superior) but the cost will be far less for eyepieces like the modified Koenig 70 degree AFOV University Optics MK-70 and the various Erfle variants that are currently on the market. The Meade QX - http://www.cloudynights.com/documents/BurgessSWA.pdf - will probably work fairly well as has already been mentioned.

Unless you want to go the focal reducer route, I suggest a 2" 40mm MK-70 for a maximum true field of view at a reasonable price.

A Tele Vue Radian or a Pentax XW (or a used XL if you can find one) will solve the short focal length, short eye relief problem. I don't care for the standard Vixen Lanthanum oculars very much, but the wide-field versions are pretty good.

The need for a three lens element "apochromatic" Barlow is merely advertising hype. See http://www.televue.com/ask_al/Ask_Al_Frame.asp?AATopic=barlows (Barlow question - Jeff Richards) for a discussion. If you really want the best "image amplifier" available, get a Tele Vue Powermate - http://www.televue.com/engine/page.asp?ID=42

Dave Mitsky

randb
2006-Mar-10, 02:43 PM
Since you have a slow f/10 scope, a well-corrected-for-astigmatism design such as the Tele Vue Nagler is not strictly necessary. You'll be giving up the ultrawide 80 degree plus apparent field of view of the Nagler and Meade UWA designs (I have heard from more than one source that the old Japanese UWA versions are superior) but the cost will be far less for eyepieces like the modified Koenig 70 degree AFOV University Optics MK-70 and the various Erfle variants that are currently on the market. The Meade QX - http://www.cloudynights.com/documents/BurgessSWA.pdf - will probably work fairly well as has already been mentioned.

Unless you want to go the focal reducer route, I suggest a 2" 40mm MK-70 for a maximum true field of view at a reasonable price.

A Tele Vue Radian or a Pentax XW (or a used XL if you can find one) will solve the short focal length, short eye relief problem. I don't care for the standard Vixen Lanthanum oculars very much, but the wide-field versions are pretty good.

The need for a three lens element "apochromatic" Barlow is merely advertising hype. See http://www.televue.com/ask_al/Ask_Al_Frame.asp?AATopic=barlows (Barlow question - Jeff Richards) for a discussion. If you really want the best "image amplifier" available, get a Tele Vue Powermate - http://www.televue.com/engine/page.asp?ID=42

Dave Mitsky

Thanks for your input Dave. I'll look into the EPs mentioned above, and if I have any questions, I'll post them here. :)

Dave Mitsky
2006-Mar-10, 03:23 PM
You're welcome. There are many reviews of various eyepieces at http://www.cloudynights.com

There's one on the U.O. MK-70s and the MK-80 at http://www.cloudynights.com/documents/konig.pdf

Tom liked the 32mm MK-80 quite a bit. Unlike many of the other U.O. eyepieces, including the 25 and 40mm MK-70s, I've never used the 32mm MK-80 but it might be a very good choice for your SCT.

My review of the 8mm Radian is posted at http://www.cloudynights.com/item.php?item_id=326&pr=2x7x123

How does the Pentax XL compare to the XW? See http://www.cloudynights.com/documents/pentax.pdf

There's a review of one of the Powermates, the same one that I own, a 2.5x 1.25", at http://www.cloudynights.com/item.php?item_id=473

Dave Mitsky

Dave Mitsky
2006-Mar-10, 03:24 PM
Has anyone tried any of the William Optics SWANs and UWANs?

See David Knisely's review at http://www.cloudynights.com/documents/swan.pdf

Dave Mitsky

redshifter
2006-Mar-10, 08:25 PM
I have two of the Vixen Lanthanum widefield eyepieces, the 42mm and 17mm, both of which I like and they are my primary eyepeices. My 42mm could have more contrast, but I'm using it in a f 4.7 scope so the exit pupil is huge - too big really. So that may be why it doesn't have a lot of contrast, that and the very low (29x) power. Still, it's pretty cool to get M8 and M20 in the same field of view. I agree with aurora above, stay away from plossls below 10 and even 15mm, the eye relief is just too short IMO.

turbo-1
2006-Mar-10, 09:32 PM
If I may make a suggestion: if you can get a high-quality 2" Barlow in 2x and another in 3x, you can generate a lot of different magnifications with just a few eyepieces, and you will retain the long eye-relief of the longer fl eyepieces. That way, you can avoid buying a menagerie of eyepieces and concentrate on getting a few very nice ones. The trick is to generate a table of what powers you get with 2x and 3x, and select the eyepiece fl that will get you the best spread and the least amount of duplication. Then, as years pass, you can "fill-in" with some more of those special eyepieces you're lusting after.