23 replies to this topic

[cpsTN]

I have a 6" f/12 (152/1836) GSO Classical Cassegrain OTA and 2" diagonal on the way. SInce nearly all eyepieces work well with such a long focal ratio, you'd think eyepiece selection would be easier, but I am not finding it to be that way. I am looking into 18mm ad 25mm to start, so I figured plossls would be fine, particularly since I like good eye relief and those FLs, even in plossls are still good. Then, I started considering AFOV. I was thinking of Orthos and that they have always been considered excellent for what will be primarily have Lunar and Planetary scope, but I, at least want to be able to see the whole Moon in the FOV for eclipses and, at 40* FOV, that will not work. Panoptics look great but I just don't know. In the 34 years I have been observing, I have never had what would be considered high-end EPs. I am also thinking of getting higher end EPs but, then again, most EPs at f/12 will be sharp on axis. It will be mounted upon Orion's Skyview Pro, currently manual, and used with 2x, 3x and possibly 2.5x barlows. I can go to a couple hundred dollars each, but I am torn. 

Edited by cpsTN, 27 February 2021 - 01:38 PM.

[SeattleScott]

APM 24 UFF or ES 24 68 is in that range.

Or this but it is a bit more https://telescopes.n...e-eyepiece.html

For an 18mm the Tak LE is really sharp, but again a bit more, and only 52 AFOV. A 17mm Hyperion could be the ticket, or 18mm UFF/UHD/Edge, etc.

Paradigm 18mm or Xcel LX 18mm would be cheaper, but neither is well regarded. At F12 it might not matter much.

Scott

[sportsmed]

Well there are alot to choose from in that price range, high end you could look into used Delites, Morpheus, ES 68's or 82's, Hyperions, Meade PWA's, the list goes on. At f/12 alot of EP's will do well, also the X-Cel LX 25mm would be a good option for under $100. I have the 25mm, 18mm and 9mm and really like that series for the price. The 18mm is my least favorite though, I would probably look for another option for that one.

[ngc7319_20]

25mm range: If you want eye relief then yes APM 24mm UFF is one of my favorites with 65 deg AFOV.  The Astro-Tech 27m FF with 53 deg AFOV (Orion EF WideField and many other clones) is also nice, and should be OK at F/12.  The TeleVue 24mm Panoptic has pretty short eye relief -- if you need good eye relief I don't recommend it.

 

19mm range: If you want to go down to 17mm then the Baader Morpheus 17.5 (76 deg AFOV) and TeleVue 17.3mm Delos (72 deg AFOV) are very nice and lots of eye relief.  Again the TeleVue 19mm Panoptic has very short eye relief.  I find the field edge in the Astro-Tech 19mm FF kinda soft at F/5 and not sure how it is at F/12.

 

Consider buying used here, and will save a bunch of money.

Edited by ngc7319_20, 27 February 2021 - 02:37 PM.

[jimhoward999]

As you know almost any eyepiece will work fine at F/12.    But, when you bring dollars into the equation and try to maximize value that is when things get confusing.

 

If you were to get a premium eyepiece something like a Delite 18.2mm for $256, it seems like it would do what you want (or similar from pentax or baader etc).  The only drawback would be that you might find something cheaper that would work as well...but that just gets into an endless cycle of researching and review reading and so forth.  If you stick with premium eyepieces then your only downside is money.

[Gaitaslibre]

 I have the same GSO optical tube and it performs really well with the GSO Superview eyepieces. The big ones, 50, 42 and 30mm 2” are really nice for getting a larger FOV out of an f/12 OTA. The smaller 1.25” plossls also work well. I have a nice set of Pentax XW’s to compare them to and at f/12 the difference is incredibly small but the price isn’t !  You see a bit more of a difference in my apo ED f/6 refractor but the GSO’s are still really good. Mid-priced optics have gotten so much better over the years.

 

Don’t worry about having to spend $350 apiece for eyepieces if they will be used in long f OTAs. The reviewers are telling the truth. If you’re going to also use them in f/6 or faster telescopes then the top of the line Televue, Pentax,  Baadler,  etc eyepieces may be worth the investment.  
 

Enjoy the 6” CC; properly collimated it gives similar experiences to a high quality 127 Mak and cools down a lot faster.

[SeattleScott]

You might consider the 7 and 10 Luminos. These are the best in the series and perform respectably even in fast scopes. At F10 it is hard to tell the difference between my $120 Luminos and my $320 Nikon. At F4 it is easier to see why the Nikon costs more. But in slow scopes these eyepieces are excellent and affordable.

Scott

[pweiler]

The big heavy EP’s may introduce some balancing issues to consider and how to counter.

[noisejammer]

24 mm Panoptics have pretty tight eye relief so they may not work for you.

 

Without a budget, it's hard to give useful guidance but I find the (Made in Japan) Series 3000 or 4000 Meade 26 'super Plossl' is excellent. These have to be looked for in the used market but they're optically excellent. The Tak LE series is excellent (albeit pricey) and Vixen LVW 22 is also excellent ... but it's long out of production.

 

I have a pair of APM 18 UFF's - good eyepieces with enough eye relief. I don't need a lot of eye relief so my 16T5's get used more.

 

Perhaps you should take a look at Don's eyepiece buyer's guide.

[Russ S.]

Maybe you're overthinking this, you originally mentioned plossls, but never said why these aren't the answer. They're fantastic for planets with plenty of fov, and work great on the moon too. The last time I looked at the moon a couple weeks ago my 15mm TV plossl in my 4 1/2" refractor gave the best view that encompassed the whole thing. I'd think a 18-20mm plossl would give the same results with your 6", and the 25mm you mentioned would definitely work. Wide fields are great, and allow greater mags on the moon while keeping the whole pie in view, but if $ is a factor it's hard to beat the simple, excellent, tried and true plossl.   

 

I think it's funny how the plossl is often overlooked or disregarded. Folks seem to either want wider or narrower with orthos. It's the Rodney Dangerfield of EP's that doesn't get much respect, probably just too boring in the world of latest and greatest    

[cpsTN]

24 mm Panoptics have pretty tight eye relief so they may not work for you.

 

Without a budget, it's hard to give useful guidance...

from my original post, "I can go a couple hundred dollars each". 
 

[cpsTN]

Maybe you're overthinking this, you originally mentioned plossls, but never said why these aren't the answer. They're fantastic for planets with plenty of fov, and work great on the moon too.

 

I was thinking that I didn't want to be restricted to 52* AFOV because the scope is already f/12, but I didn't want to go, necessarily to 76-82* AFOVs if I wouldn't be able to tell a great difference. I have decided upon the 18 and 25 Paradigms at 60* AFOV @ only $60 each. They are already on the way. I think it is a good compromise. I can always move up from there later.
 

[MartinPond]

A Paradigm at 15mm or over is extremely happy with F8,

  (more than with F5), so you can't lose at F12.

 

If you wanted to go extra-premium later, hey, you only dropped $120.

[Russ S.]

I was thinking that I didn't want to be restricted to 52* AFOV because the scope is already f/12, but I didn't want to go, necessarily to 76-82* AFOVs if I wouldn't be able to tell a great difference. I have decided upon the 18 and 25 Paradigms at 60* AFOV @ only $60 each. They are already on the way. I think it is a good compromise. I can always move up from there later.
 

Sounds like a wise plan, and I hear good things about them. I was going to also suggest the longest Delite, 18.2mm @ 62*, just a little north of your budget and everyone raves about them. Maybe in the future if the Paradigms leave you wanting a little more? Good luck!

[luxo II]

I have a 6" f/12 (152/1836) GSO Classical Cassegrain OTA and 2" diagonal on the way. SInce nearly all eyepieces work well with such a long focal ratio, you'd think eyepiece selection would be easier, but I am not finding it to be that way. I am looking into 18mm ad 25mm to start... I can go to a couple hundred dollars each, but I am torn. 

Ultraflat-field (UFF) would be nice in your scope, and 30mm, 24, 18, 15 and 10mm available... and within your budget.

Edited by luxo II, 28 February 2021 - 11:29 PM.

[k5apl]

I own a 102mm f13.2 refractor and my favorite eyepiece is a 28mm Edmund Scientific RKE.  Views are out of this world!  I also have a 14mm and 9mm Morpheus.  And a 5.5mm E.S. eyepiece (66 deg?).  Most eyepieces will work well with flat field and sharp to the edge; I find my challenge is framing the view of what I generally look at.

Let u know what you decide...............

[starcanoe]

A Paradigm at 15mm or over is extremely happy with F8,

  (more than with F5), so you can't lose at F12.

 

If you wanted to go extra-premium later, hey, you only dropped $120.

 

I have those..a 12 and an 8....I bought them for higher power views with my 6 inch f8 dobs....very nice IIRC so yeah...will work fine at f12 for sure.

 

Only downside is a spurious reflection when you view something bright like the planets...more distracting than an actual problem. Oh...I might have those that are a rebrand of the actual para dig em eyepieces...will try to look at my kit later and get back to the OP.

[By-tor]

The Paradigm's were highly recommended in another thread as my first nice eyepiece and since the 18mm was the only one in stock at Astronomics I ordered one to use with my Meade 125 Mak. which is f/15.  It arrived yesterday, but with our crap weather I'm not able to get out under the stars and try it out.  I can say it's a very solid eyepiece and I like the adjustable eye relief cup.

 

I'm hoping to use it soon..

[MartinPond]

I have those..a 12 and an 8....I bought them for higher power views with my 6 inch f8 dobs....very nice IIRC so yeah...will work fine at f12 for sure.

 

Only downside is a spurious reflection when you view something bright like the planets...more distracting than an actual problem. Oh...I might have those that are a rebrand of the actual para dig em eyepieces...will try to look at my kit later and get back to the OP.

Sounds like 'veiling glare'.

That seems to come and go at different FLs of the same product line.

It appears and disappears in Meade 4000s.  Some extra irising helps.

F12 helps a bit, too.

[starcanoe]

I don't think I'd call it veiling glare.

 

It IIRC...not observed in awhile    was a disk of light that did not coincide with the image of say jupiter.

 

If Jupiter was off to left a bit say...there would be a detectable disk of light off to the right. Now since one was not superimposed over the other it had no practical effect on the image. Just a bit distracting for the perfectionist types.

[MartinPond]

Like ghosting, but stronger..

Almost seems like an element is out of alignment or something.

[barbie]

For my F14 90mm Maksutov, I like to use an 18mm Takahashi orthoscopic both at native focal length and with a 2x Barlow for 9mm. I also like and recommend Astro-Tech Paradigm ED eyepieces. At 60 dollars per eyepiece, they are excellent. Wide angle eyepieces work well as do Plossls.

[starcanoe]

Looked at my eyepieces ..they are 12 and 8 mm "starguiders"...probably a clone of XYZ?

 

I am pretty happy with them at f8 so should only be better f12.

[SeattleScott]

Clone of Paradigm, Dual ED, etc. I’m sure they will be fine at F12.

Scott