more questions about eye pieces

[Ziggy]

Hi Guys,

I know this has been done to death on here, and I've been reading heaps of posts and reviews on various eyepieces, but just have a couple of questions of my own.

More asking for advice I think, though I know it's hard for others to say what will suit my needs. Anyway, I'm in a position to buy one quality eye piece. It's for a 9 1/4" SCT. I have a barlow by the way, (though fairly cheap).

I guess I want something good for planets and lunar observing, but equally something for DSO as well....how many times have you heard that?? Most of my observing is done from the yard, so I guess you would say conditions are average as far as street lights and seeing goes.

Is the Pentax 10mm XW a good choice? The magnification would be 235x in my scope. I was also thinking the 14mm, (167x), but leaning towards the 10mm. I guess I'm asking which is the better all round piece? I could use a 9mm or 7mm UO for specialised Planetry views I suppose.

I guess I like the wider field of view the Pentax, to help see those DSO, (things such as the Orion Nebula and so on), plus they seem to have a very good reputation with regard to planetry observing too. I was thinking of coupling this with a couple of UO Abbe HD's. Maybe the 7mm and 18mm. Surely you can see some of the smaller DSO with these eye pieces, despite their smaller field of view? And I know their reputation for viewing planets is very good also. Is the 18mm HD very useful? Maybe in that size a wider field might be more useful too.

Any advice would be appreciated. I favour the 10mm Pentax, and 7mm & maybe 12 or 18mm UO HD, but still have thoughts about the 14mm Pentax, and 9mm & maybe 12 or 18mm UO HD. Or a variation of those. Or forget the HD's and just get both the 10mm and 14mm Pentax, but that is getting close to a $1000 for just 2 eye pieces.

Suppose someone is going to tell me the 13mm Nagler is better than the lot

I'm open to suggestions! Then of course there's the 22mm, 24mm or 27mm Panoptics. Does it ever end. Guess I want to sort out my high - medium power pices first.
I'm not really in a position to test any of them unfortunately, but having done plenty of reading, they all seem like excellent pieces.

Sorry for rehashing the same old subject, but any thoughts will be much appreciated.

Glen.

[Robert_T]

Hi Glen, get a toucam or neximage and you'll never use an eyepiece again

Ok, maybe that's just me. "Xreckor" - Rob Charteris - has a few XW's and speaks convincingly and passionately as to their merits so he may be the best to comment on these. One caution though is eyepieces will perform differently in your SCT compared to a newtonian like Rob's.

I wonder about how well any one eyepiece can excel at different tasks, though it depends I guess on one's expectations. If it were me interested in both planetary and deep sky I'd get the one high quality, high cost, wide-angle eyepiece like the XW that achieved medium power ~120-200x for use in deep sky and some lunar/planetary, and supplement with UO eyepieces (which for $80 to $125 for the HD version are good value). I use the 18mm UO HD as my starting eyepiece for planetary and lunar - used in C9.25 like yours and a slightly shorter focal length 7in dall-kirkham cassegrain. The 18mm provides a good starting power to sus out the seeing and sometimes may be as high as you want to go anyway. These eyepieces should be fine for smaller deep sky objects, eg planetary nebs etc too though I haven't used them for such.

hope this is of some value.
cheers

[g__day (Matthew)]

I use either a UltraWide 22mm lens (low magnification, wide field of view) or a Meade 8mm - 24mm for variable work including viewing planets and am quite happy with the performance of both.

The Zoom lens actually works surprisingly well. Both where around the $380 - $450 mark.

[Starkler (Geoff)]

Glen , what you havent mentioned to us is what eyepieces you already have.
What do you think is missing in those eyepieces or what characteristics need improving on ?

People will choose a nagler for one reason, or a pentax xw, or a panoptic, televue plossl for others, matching up the desired characteristics and budget allowance.

In an sct, most eyepieces should work well as regards edge correction.

Knowing what you really want will help narrow down the field and make the best use of those hard earned dollars.

A general rule might be to make your first premium eyepiece one with around a 2mm exit pupil, which will likely be your most used eyepiece for general dso viewing.
If you can handle 2" eyepieces, the 22mm panoptic is one of the best choices.

[Glenn Dawes]

Hi Glen and all,

I recently discovered a great beginner level discussion on the web about eyepieces.

http://observers.org/beginner/eyepieces.freeman.html

check it out.

Also, I am considering buying a Meade Super Wide Angle Series 5000, 16mm ep for my 10" f5 Bintel Dob (I can't afford a Nagler). I'm looking for a nice wide flat field of view (ie focused to the edge of the field). Does anyone have any experience with this combination?

Regards

Glenn Dawes

[Ziggy]

Thanks guys for your responses. at the moment I only have the 25mm Plossl that came with the scope. I guess I'm looking for something with more magnification. I like the idea of a UO HD or two. Specialty planetary and lunar eye pieces. And then something with a wider field, for DSO. Been thinking about it at work, and I think the Pentax 14mm might be the better choice, but it's all guess work for me.

Fortunately I'm a great procrastinator, so I won't be rushing into anything! The 22mm Pan sounds very nice too. I'm making a list, and I'll narrow it down bit by bit.

Thanks for everybody's help, and anyone else with any ideas, please feel free to leave your suggestions. I will take notice!

Cheers,

Glen

[RAJAH235]

Glenn D, closest I can come for comparison is a Meade S4000 SWA 18 mm in a members Orion 10" f5.6. How's that? Gave very nice O/A view. No app softening @ the edges. Should be O.K. in your f5. Worked fine in my f4.5.
L.
ps. Are the 5000's still 67 degs app fov?

[ballaratdragons (Ken)]

One EP that does Planetaty and DSO's. Hmmm

Probobly something in the range of 15mm - 20mm. 20mm will give you small planets but brighter DSO's. 15mm will give you slightly bigger planets (not much bigger) and slightly duller DSO's.

Depends on the DSO's as well. Galaxies will lose light rapidly the lower the mm. But Globs and Orion Neb etc are pretty good in just about any EP.

I believe you will need 2 different EP's for good viewing of both Planets & faint Fuzzy DSO's.

[ausastronomer (John Bambury)]

Originally Posted by Ziggy

Thanks guys for your responses. at the moment I only have the 25mm Plossl that came with the scope. I guess I'm looking for something with more magnification. I like the idea of a UO HD or two. Specialty planetary and lunar eye pieces. And then something with a wider field, for DSO. Been thinking about it at work, and I think the Pentax 14mm might be the better choice, but it's all guess work for me.

Fortunately I'm a great procrastinator, so I won't be rushing into anything! The 22mm Pan sounds very nice too. I'm making a list, and I'll narrow it down bit by bit.

Thanks for everybody's help, and anyone else with any ideas, please feel free to leave your suggestions. I will take notice!

Cheers,

Glen

Glenn (ziggy)

I own a full set of UO HD orthos and also 4 Pentax XW's. I have also used most of the televue eyepieces.

The 10mm Pentax XW is 1 of the best eyepieces I have ever used but I don't think its right for your scope, as the 235X magnification it gives, will not hold up all that often due to atmospheric turbulence.

With the long focal length and narrow FOV of the C9.25 OTA (which IMO, is the best small SCT OTA) I think you would be better off going with either the 24mm or 22mm TV Panoptic. The 22mm is probably a slightly better eyepiece than the 24mm but its more expensive and somewhat larger with a 1.25"/2" dual fit barrel. The 14mm Pentax XW shows minor field curvature in faster scopes but works very well in an F10 SCT and I think this is an excellent medium/medium high power option. I would then get a good 2X barlow to use for your planetary viewing. Your better off with a couple of good eyepieces and a high grade barlow than a lot of lesser eyepieces. The UO HD orthos are very good planetary eyepieces but in a SCT they give a very narrow FOV combined with short eye-relief.

At some point in the future I think you also need to consider a good quality low power/wide field eyepiece like the 35mm TV Panoptic.

I wouldn't waste my time using the barlow you have with a Panoptic or Pentax XW, the quality of the sytem is only as good as the weakest link. If your going to use high grade eyepieces you need a high grade barlow.

CS-John B

[ausastronomer (John Bambury)]

Originally Posted by Glenn Dawes

Also, I am considering buying a Meade Super Wide Angle Series 5000, 16mm ep for my 10" f5 Bintel Dob (I can't afford a Nagler). I'm looking for a nice wide flat field of view (ie focused to the edge of the field). Does anyone have any experience with this combination?

Regards

Glenn Dawes

Hi Glenn D, good to see you join the forum !!

Obviously you aren't happy with the 15mm GSO superview you had at SPSP? Not great at F5 IMO !!

Haven't used the S5000 Meade 16mm SWA but I have used the S5000 Meade 14mm UWA and I can tell you that its not a real good performer at all in an F5 scope especially considering its $350 plus !!! price tag. I am told that the 14mm is not up to the other focal length S5000 UWA's.

Something else to consider are the Orion Stratus series. You could go for either the 13mm or the 17mm. These offer a 65 deg AFOV and 20mm of eye-relief. They can be ordered through Bintel or direct from USA and will cost you about the same as the meade S5000 SWA (about $260). The Orion Stratus are clones of the high grade Vixen LVW's.

Here is a link to a good review on them.

http://www.svenwienstein.de/HTML/hyp...h_version.html

I know that Steve (Janoskis) recently sold his 13mm nagler T6 and kept the 13mm Orion Stratus. Send him a PM and ask him his thoughts on the Stratus. My guess is that these will outperform the Meade S5000 SWA.

CS-John Bambury

PS- Did you ever get that Jupiter applet I sent you working ?

[Roger Davis]

Didn't think there was such a beast as a high power planetary/DSO eyepiece.
DSO's require aperture not magnification. The higher the mag the dimmer the object through light loss. Also a larger apparant field helps.
Lunar or planetary observations are restricted in the mags by seeing conditions/transparancy. Not often that you get to use more than 200X and get good images (unless you live on Mauna Kea). You also don't need a large apparant field.
Best advice has already been given by others. An eyepiece between 15mm-20mm for DSO's and for planetary use you can get a Powermate instead of a barlow, you will be hardly aware that the Powermate is in the optical train (they work slightly differently to a barlow).

[ausastronomer (John Bambury)]

Originally Posted by Roger Davis

Didn't think there was such a beast as a high power planetary/DSO eyepiece. DSO's require aperture not magnification.

Roger,

Thats a comment I wouldn't have expected you to make, its clearly incorrect in a lot of cases IMO.

There are countless DSO's that are best viewed at higher magnification given the aperture available. Numerous Globulars, Planetary Nebular and Double Stars all "can" provide "better" views when viewed at medium/medium high power. As you would be well aware, many planetaries appear almost stellar until you crank things up a bit. The Homunculus is a classic DSO target that is better viewed at high power.

Originally Posted by Roger Davis

The higher the mag the dimmer the object through light loss.

That's true, but don't forget that as magnification is increased, contrast is also increased, up to a given point where light loss causes the target to become too dim. That isn't an issue in a 9.25" scope at the magnification we are talking here and the targets I think Glenn is planning too observe.

I think Glenn actually described his requirements perfectly, indicating that he wants an eyepiece that gives him enough power for lunar/planetary viewing, but could also be used for observing DSO's at those powers. Consequently, a wider AFOV would serve him better when combined with the longer focal length/narrow FOV of his SCT, than something like an orthoscopic or plossl which are not as suitable for high power viewing of DSO's in a slow scope.

Granted, anyone that plans to work mainly on DSO's requires a couple of premium low/medium power eyepieces, they also will require something that gives good quality views around 200X and that is exactly the range Glenn (ziggy) is looking too purchase something.

CS-John Bambury

[Stu]

Glen,
I have the 15mm, 22mm and 35mm Panoptics. They are all excellent and are still the sharpest eyepieces that I have used in short scopes. But John makes a good point that in a SCT you may not notice the difference, so you don't have to spend that much if you don't want to.

If you do not wear glasses, I can not recommend a better EP (in the focal length range you need) than the 15mm (or 19mm) Panoptic. The 15mm has slightly over ten millimeters eye relief which is heaps for me and would give you about 150 - 160X in your scope, with 1.5mm exit pupil, and it's cheaper than XW's. It's only $350 from bintel.

Panoptics are very consistant across the range. The Meade 5000 series are not. I owned four series 5000 plossls and there were differences. Same with the SWA and the UWA's have a couple of bad ones but the rest are good, so try before you buy.

If you are going to go any smaller, the 10mm XW is apparently the best but I have not tried it. I can't comment on the 14mm XW. I think the 15mm Panoptic might be a better choice based on price anyway. But if you need the eye relief then the Pentax's are the best choice untill you get up to a 20mm EP.

If you are going to go larger, the 22mm panoptic is awesome. I bought the 22mm because it had the dual 1.25" and 2" barrel. You can use it as either type, just as it is, without removing anything. Optically sensational.

The 35mm will be a bit big for what you want to do I think. But if you decide you want it, you will have to buy it new because I will never sell mine! (And probably no one else will sell theres either).

[Ziggy]

Ooops, missed the eyepiece forum when I started this thread. Very sorry.

Thankyou to everyone for their contributions. Particularly John, (ausastronomer), learnt a lot from your posts. But to everyone, really appreciate the time you take to write. I know you all know your stuff, and most of the recommendations seem to be heading in the same direction, so I'm pretty confident in how I'm going to go now.

The Panoptic 22mm is looking pretty good to me. Still like the Pentax 14mm, but the Pan 15mm is an option. Will definately buy one in the next week or so, and then look at the other a month or so later.....find it a bit hard to spend too much money all at once! And one more lower pwer one after that, and I will be set....hopefully! But I can certainly see that quality is the way to go.

Once again, thanks everyone. I'm fairly new to astronomy, but learning heaps from this site everyday

Glen

[Rodstar (Rod)]

Hi Ziggy, it is always fascinating reading others' thoughts on EP's.

I have an f/10 SCT, which I assume is the same f/ratio as yours.

If you are looking for a good EP for both planets and DSO, I agree with the other comments about the 22mm Panoptic. Marvellous!

I recently bought the 22 Panoptic and a 13mm Nagler to upgrade my EP collection. I use the 22 Panoptic far more than the 13mm Nagler. More nights than not, air turbulence around my area will not support the magnification of the Nagler (192x). Mind you, when the seeing is up for it, the Nagler is fabulous too! I could not recommend any EP more highly than the 22 Pan.

I am currently trying to find some thing with a little less crank than the 13 Nagler. I'm think of something around the 16-17mm mark, and the Orion Stratus is on the top of my list at the moment because of financial constraints.

Good luck with chosing. And happy observing!

[ausastronomer (John Bambury)]

Originally Posted by Rodstar

I have an f/10 SCT, which I assume is the same f/ratio as yours.

Rod,

Glenn's Celestron C9.25 is an F10 scope but because of smaller aperture the Focal length is only 2.35 metres compared to 2.54 metres with your 10" LX200. Consequently the 13mm Nagler in Glenn's scope is only giving 180X compared to about 195X in your scope. The 14mm Pentax XW in Glenn's scope gives about 170X and should be ideal as a medium high power eyepiece and should hold up on most nights of reasonable seeing.

CS-John B

[MarkN]

G'day Ziggy

Don't feel hard done by if you forgo the Naglers and Panoptics. These EPs only give of their best with "fast" scopes. As someone already stated, your "slow" F10 SCT will work perfectly well with more modestly priced EPs. And you need not feel insulted by that. Why spend more if you don't need to!

I live in a pretty heavily light-polluted suburban area (Wollongong) and I can say that unless I go to either of my astronomy clubs outings, the 9 mm T4 Nagler is rarely taken out of its box. The 220 X magnification it yields in the LX90 is very poor quality.

FWIW the 32 mm UO Konig (2" format) purchesed from Frontier Optics gets the most use followed by the 17 mm T4 Nagler.

You will find a wealth of telescope info here and also on "Cloudy Nights". In particular, look up their tests and review section. You will find it very useful.

And now, crappy skies or not, I'm getting the scope out.

Great viewing all.

Mark.

[Rodstar (Rod)]

Originally Posted by ausastronomer

Consequently the 13mm Nagler in Glenn's scope is only giving 180X compared to about 195X in your scope. The 14mm Pentax XW in Glenn's scope gives about 170X and should be ideal as a medium high power eyepiece and should hold up on most nights of reasonable seeing.

Thanks for that, John. Yeah, I would have thought you would get a lot of use out of an EP at the 170-180 magnification range.

[Glenn Dawes]

Originally Posted by RAJAH235

Glenn D, closest I can come for comparison is a Meade S4000 SWA 18 mm in a members Orion 10" f5.6. How's that? Gave very nice O/A view. No app softening @ the edges. Should be O.K. in your f5. Worked fine in my f4.5.
L.
ps. Are the 5000's still 67 degs app fov?

Thanks for your observations. If the S4000 SWA works on an f4.5 well then (hopefully) the S5000 should be at least as good. In theory, the more elements in an ep the better sharpness out to the edge. The s4000 units are 5 elements, the S5000 are 6. Anyway, I took a punt and got the s5000 18mm. Also they advertise it as 68 deg. AFOV.

I'm hoping to get up to Kulnura on the evening of the 1st to meet some of you guys and to give this ep first light.

Regards

Glenn D

Hey Glen (Ziggy)

Like John "ausastronomer" I'm a XW (3.5mm, 10mm, 14mm) and U/O HD (7mm, 9mm,
12mm & 18mm) owner. Although I very rarely use the HD's anymore I think I would
miss them if I sold them. Besides their apparent resale value does not make it worth
selling them.

I agree with John about the 14mm XW has some EOF softness in my f/6 newt. But
it's contrasty nature and on axis performance is superior in my book to none. It's
my most used dso ep @ 85x in my 8" f/6 newt. Even over the 18mm HD. The 14mm
XW actually gives me a bigger FOV the the 18mm HD. For planetary I usually barlow
the 14mm and 10mm XW's. And when conditions permit you cant beat the 3.5mm.
I even had alot of fun peering at the cores of galaxies with the 3.5mm most
memorable was M 104 where the knoting in the dust disc transiting the central bulge
was quite apparent.

Although I have tried my XW's in a few different scopes I dont remember any of
them being a SCT so I cant comment there really except to say. The 14mm will
prolly perform better at a longer FL as has been sugested. The other thing is
no one ever commented on the EOF performance either. The 10mm is the bees
knees for flat, tact sharp across the entire field viewing with a slight cromatic
abbrevation at the extreme EOF, with the 3.5mm performing the same.

I look forward to the day when I also have the 5mm & 7mm

My choice for wide field is a 20mm T5, I would go for the 20mm XW but it comes
in 1.25" format. And I want to go 2" at those powers, which will eventually have
2" filters. Plus I dont want to be swapping out adaptors all the time.

I think you have had some pretty good advice from all sides. The thing about good
quality premium ep's is you will always keep them, if they're good : ) and they will
perform across a range of scopes. Yes you could spend a lil less for something that
will work just as well in a long FL scope but what happens down the line and you
change to a fast FL... you want to go out and buy ep's again? just something
to consider

regards,CS Happy New Year! all