View Full Version here: : Vixen LVW or NLV
17-04-2012, 11:57 PM
Hi Vixen eyepiece users,
I am wanting to finish my small eyepiece collection...if thats possible, and have boiled down my choices to NLV or LVW's. I'm wanting a 13, 8, 7 and 5 or thereabouts. For say a 5mm FL apart from the difference in FOV is there much of a difference in the image in brightness, contrast etc. I know I should look through these things at a star party but haven't yet. Not sure which way to jump:help: My other reasonable eyepieces are ES 68 degree 20 and 16mm. Was thinking of adding some 82 degree series, maybe I should, but some reviews are not so favourable.:confused2: DSO and Planets are on the viewing menu..
18-04-2012, 12:09 AM
I'm a spectacle wearer and ultra-wide fields don't really do a lot for me, I'd much rather have lots of eye-relief and a very sharp contrasty image. The LVW's give 65 degree fields of view, the LV and NLV series give 50-52 degree fields. In my scopes the LVW 5, 8 and especially 13 are my favourites; in your Newtonian the 17mm would be fine too. I have these plus the 22mm and an NLVW30mm (I would suggest you don't buy this).
I also have a set of LV's (LV5, 7, 10, 15 and 25mm) for my smaller refractor, they are very comfortable to use for long periods, high transmission and excellent contrast, little or no colour. The NLV's are the same glass but with a fugly fat plastic shroud.
At the long end I much prefer the TMB Paragon 30 or the Vixen LV50 (but its a 2" monster) over the NLVW30 which isn't so sharp, these are all fine on my 102mm f/7 refractor by they won't suit an f/5 Newtonian.
I have tried a couple of ES eyepieces and didn't like them so much.
18-04-2012, 05:55 AM
I've got the LVW22 and LVW13 and the LV9, LV6 and LV4 that I use with the 10" newt. I've very happy with all of these. I went for the LV's instead of LVW's for the shorter focal lengths (higher mag) as I figured wider fields were not that important when you are trying to view a planet.
18-04-2012, 09:04 AM
I have the 40 to 5mm set of the LVWs. Best thing I've done as eye relief is excellent and I like the field of view
18-04-2012, 09:19 AM
I have three older LV's (as opposed to the New LV). As you are Melbourne based, just send me a PM if you want to borrow mine to try out.
I think they are great EPs, very sharp, great contrast.
18-04-2012, 09:40 AM
All good comments and advice below but just be aware that a Vixen 7mm fl no longer exists in the NLV's and never existed in the LVWs (you can get a 8mm LVW instead if you prefer - a highly regarded EP). If you are set upon a 7mm Vixen you will need to hunt around in the 2nd hand market to find a 7mm LV - Don't ask me why Vixen discontinued this particular fl when producing the NLV's.
18-04-2012, 11:52 AM
I think the Vixen LVs are definitely an under-rated eyepiece, well at least for the two I had - 5mm and 9mm (now not available). In the endless eyepiece quest I parted with them... I now have the LVW 5mm which I am very happy with. It seems to be well-corrected, has good transmission, very sharp, has a neutral colour and the views just seem to sparkle.
18-04-2012, 09:59 PM
Thanks for the replies,
All this helps me to go the NLV direction. Eye relief is high on the agenda as I've just got to the big 50:eyepop: Also my favourite scope is a 6" refractor at f8, and Wavytone your comment on not wanting a large field of view strikes a chord with me.
Bo, if there is ever another good viewing night:lol: ...I'll Pm you and take you up on that kind offer ...wow what a great bunch:thumbsup:
Allan ,Peter and Andrew thanks for your advice will eventually go for a mixture of the two types , got to admit the ES eyepieces are not as good as the hype but nice all the same. Suppose you get what you pay for. At least they were on sale :D Matt
19-04-2012, 12:52 AM
:) Maybe some LV's here, incl 7mm
Check the used equipment link.
19-04-2012, 07:16 PM
I would recommend the Vixen / Orion LVW's as well. Plenty of eye relief and excellent central & edge correction right down to f/4. Great eyepieces IMHO.
20-04-2012, 08:45 AM
:hi: Yep, another vote here for the Vixen LV's , mine are perfect when used in all my refractors , so easy to use , they just get out of the way and let you see all there is to see :),
As said before , these are very under rated eyepieces .
You cant really go wrong .
25-04-2012, 05:11 PM
I have a Vixen 22 mm LVW, which is a nice eyepiece, but I have to say that the Hand Grenade Sized super-heavy-weight 20 mm type II nagler, now a collectors item, beats it by a mile. (This "big kahuna", that weighs as much as a telescope counterweight, is so highly regarded that it still costs a small fortune, even on the second hand market)
Usually, I would say that Super Premium eyepieces like the Naglers are a luxury, compared to Good Quality lower priced eyepieces, but the views through the old 20 mm Type II Nagler do make the 22mm LVW seem like a toy, in comparison to the Nagler.
To me, the Vixen 65 degree field eyepieces have always seemed overrated, considering their high price.....there are plenty of cheaper eyepieces that give views every bit as good.
25-04-2012, 05:17 PM
You won't find hardly any cheaper eyepieces that will give you excellent edge correction down to F/4 than the Vixen LVW's....good luck with that!
25-04-2012, 11:28 PM
The issue of how to accurately compare the edge correction of various eyepieces , when used with short focus scopes, is important. Anyone got any suggestions as to how to evaluate this in a rational and non-subjective manner?
26-04-2012, 03:33 AM
All one needs to do is a Google search or search on Cloudy Nights for many reviews about this issue. I myself have tested hundreds of eyepieces from F/4.72 right up to F/6 using the eyepieces in their native form and with many different barlow lenses. My next purchase will more than likely be a Paracorr, which is needed IMHO with my 10" F/4.72 reflector for better edge correction on some of the eyepieces I have now.
The Vixen / Orion LVW eyepieces have been evaluated extensively down to F/4. Here is the translated site below. If you scroll down near the bottom, the LVW evaluations are there.
26-04-2012, 10:49 AM
There are better ways. But first you will ned to understand a little about the aberrations significant in most eyepieces. FWIW it is assumed here that the eyepiece you are considering gives a sharp image on-axis, i.e. it is achromatic, free of spherical aberration and free of wedge, and has been reasonably well assembled. Anything that shows these problems on-axis belongs in the bin.
1. Axial spherical aberration at the exit pupil.
This causes the 'kidney bean' effect noticeable when the exit pupil is close to the same size as your eye pupil - quite noticeable on many low power eyepieces, it is often very annoying with reflectors with a central obstruction, less so in refractors. On short focal length eyepieces ASA is not a concern.
2. Field curvature - if it is a poor match to the field curvature of your scope, you'll always have part of the field focussed and another part unfocussed. Definitely a big issue, what works well on one scope may be a poor choice for another type of scope.
3. Monochromatic aberrations - distortion, coma and astigmatism off-axis. Distortion is only a nuisance. Coma and astigmatism are worse, producing winged shaped that will never focus. The net aberration you will see is the sum of the contribution from the eyepiece and the telescope, so like field curvature, an eyepiece that works well with Newtonians may not be such a good choice for others.
4. Lateral chromatic aberration (LCA) off-axis. Basically, a star is sharp on-axis but near the edge of the field it is smeared radially into a rainbow.
All eyepieces have all of the above to a greater or lesser extent. Worse, when you have a combination of field curvature, LCA coma or astigmatism, you will see some fairly disappointing results for stars near the edge of the field of view.
How to evaluate: Forget about testing on stars, its too awkward and too subjective, and stars are generally too dim to see what's really going on when they are near the edge of the field - you need a brighter test source.
Ideally you need an optical bench with the measuring gear to look into the eyepiece and measure what is seen, but I know none of you have that.
Next best is to use a distant bright light, or an artificial star consisting of a white LED or pea-torch bulb at about 1km range. Even better, use it's reflection off a ball-bearing.
26-04-2012, 11:01 AM
Been into astronomy for about 30 years now, so I am well aware that there is no free lunch. Testing on stars is fine....done that all of my life too. The eyepiece I was considering is very sharp ON AXIS as well as OFF AXIS. I really don't need to go on any further about this.
26-04-2012, 11:46 AM
Uh oh - here we go - the age old debate of whose largely Japanese made glass is better.
Wavytone - Very good explanation of EP properties/specs
26-04-2012, 12:56 PM
Debate? There is no debate, there never was, LOL! All I did was drop a link showing a test @ f/4, nothing more. JUst got back inside myself for an observing session, was fun indeed ! :thumbsup:
Have a great day / night! ;)
27-04-2012, 04:43 PM
Thanks, bytor666 and Wavytone, for the excellent tips on non-subjective eyepiece testing. You have obviously compared enormous numbers of eyepieces, so your advice is much sought after in this forum.
I just bought a William Optics UWAN (ultra wide angle) 4mm, for use in my ED Doublet F6 4 inch apo (or, more correctly, semi-apochromatic) refractor.
Have you evaluated one of these eyepieces, and if so, what do you think of it?
(they are available in Australia, discounted, for about 200 Australian dollars)
People (such as myself, at present) who have just bought a shiny new eyepiece, often at great cost, naturally tend to have perceptual biases, with the natural human tendency being to overestimate the performance of that brand new eyepiece which may have been bought at great cost.
29-04-2012, 01:06 AM
I've just come in from a very interesting couple of hours with my 17.5" f/4.5 dob. Ol' Wavytone was very generous today (Saturday), and lent me a couple of his most prized pocessions, two of his LVW's, the 13mm and the 8mm. I was hoping to be able to compare them to my problematic 13mm Hyperion, and gererally be prepared to have my socks blown off. What happened in the end I did not expect.
What spurred this lending of Wavy's LVW's was both THIS thread, and my poor experience of my recently acquired used 13mm Hyperion. This thread without saying is a gem. My Hyperion however was a disappointment. Using the same 17.5" scope, the stars in the Hyperion refused to come to a nice, crisp, sharp focus. Sure, if you concentrated on a single star the image became pin-point, but it didn't hold. There was some sort of mismatch happening between the optics and my eyes. The field curvature was appauling too! I have never seen such a "fishbowl" effect in any eyepiece. My observing companion that night, erick here on IIS, also saw this. Major disappointment.
When Wavy' dropped of the eyepieces, we examined both 13mms. We noticed that the field lens of the LVW was convex, but that of the Hyperion was concave. Odd since this field lens arrangement is supposed to be a barlow, and should be the same if the Hyperion is a copy of the LVW.
I should note here before continuing that the bottom 1.25" section of all Hyperion EPs unwinds from the two inch barrel fitting. This is part of the modular construction of these EPs that allows for different extension rings to be used, there by allowing one EP to become of two, three or maybe even four different focal lengths. The 24mm (of which I also have one) the 1.25" barrel has no lens in it, therefore is an empty shell with a thread for filters.
My test DSO was Eta Carina. The Hyperion was terrible, as the first time I used it. The LVW was in a league of its own here. The added 3 degrees FOV of the Hyperion only provided a slightly larger AFOV, but the field stop was soft, while that in the LVW was a nice sharp edge.
Then, a fit of maddness overtook me. I swapped the 1.25" barlowed barrel of the 13mm Hyperion for the empty barrel of the 24mm Hyperion, AND to it added the barlow lens element of my $30 1.25" GSO 2X barlow. Man-oh-man! What a difference! All of a sudden, the "modified" 13mm Hyperion had found its Mojo. The bugger focused as sharp as the LVW. The field curvature was gone. The field stop was still soft, but not really of consequence, as the extra 3deg of FOV remained the same.
HOWEVER, the real difference came when I nit-picked the faint stars around in Eta Carina. Switching between modified Hyperion and LVW constantly, I was actually seeing more stars in the modded Hyperion that the LVW. A faint cluster of stars immediately beside the star Eta Carina in the LVW required averted vision to JUST see them. With the modified Hyperion, I could see these same stars directly! and them even more stars with averted vision!
Contrast wise I could not really notice any difference. Probably due to the heavy light pollution I was viewing from. But, I cannot get away from the fact that I could see more in the modified Hyperion that I could in the LVW! I was considering rolling my 13mm under a fast moving truck earlier today. I'm keeping her now! "Frankenstiened" and all.
I then moved onto the 8mm LVW. As Eta Carina had now moved into a more light polluted section of my sky, I the test DSO became the open cluster in Scorpio NGC 6231. My comparison eyepiece was my $50 9mm TMB Planetary Type II. This TMB eyepiece only has a 60degree FOV, compared to the 65degrees of the LVW. I was in for another surprise.
This modest TMB eyepiece showed better contrast than the LVW. At this magnification, approx. 200X, the background sky in the TMB was a little blacker than in the LVW. Really small, but noticeable. The same thing also happened with this TMB, where I was able to see more stars through it than in the LVW. It also focused sharper. While the FOV of the TMB was smaller, the AFOV was larger than that of the LVW, maybe 4" or 5" (minutes of arc that is).
All of a sudden, I am at a bit of a loss at what has happened tonight! I had expected to have my eyeballs assulted by the quality of the LVW, but they have been out done by a modified Hyperion, and a $50 TMB. I am guessing that the edge that the TMB also has is the bugger all glass it contains compared to the LVW. Still, I would not have imagined such a significant difference.
I have now reconsidered my eyepiece collection from what I had been thinking only upto four hours ago. Sorry all of you LVW affeccionados - you have lost me. Coming to this shoot-out tonight, I had been gunning for the LVW's. In the end I've got new champions, and they were in my eyepiece collection all this time!
29-04-2012, 03:37 AM
Looks like you had a defective LVW because there is no way that any Hyperions or TMB planetaries would be any better than those eyepieces. I have tested an 8mm LVW and stars were all pinpoints from the center right out to the edges in my 10" f/4.72 reflector. I am talking nice tiny points of light here. I also put an LVW up against a barlowed 13mm Hyperion and the LVW bested it.
BTW, The field curvature is not coming from your eyepiece, it is coming from your mirror as I see it is @ f/4.5. Another thing, the field lenses of both the hyperion and the LVW do not a have a "barlow",they have a "smythe" lens.
29-04-2012, 07:39 AM
First, I can't make an appology for what I saw down the eyepiece. I came to this evenings session completly with an open mind. No prejudice towards my gear, actually I favoured the LVW's. I very much looked forward to using these LVW's, particularly after reading your comments and Wavy's.
Symthe lens or barlow, I used the term as a description only by the way this lens has been described in many other threads I've read. Doesn't change things though. The only true "barlow" then is the one I stuck in the end of my Hyperion.
No, niether of these LVW's are defective. They are both superb eyepieces.
Field curvature comeing from the mirror. Could be. My definitions on optics is limited, so I apologise if I used the incorrect term here. "Fishbowl" effect then. The image displayed a distinct deformation as the scope was moved across the field, like that seen in a big, fat magnifying glass. I can only guess that there is some miss-match of "smythe" lens with my 13mm Hyperion. I have read only good reports from other 13mm Hyperion users, so I'm at a loss to know what happened there.
Come to think of it, yes, the field was tighter across a wider stretch of the FOV of the LVW, but the FOV distortion in the Hyperion only occured in that area that extends beyond the field stop of the LVW. Over the same FOV area, nope, I can't say I noticed any real difference.
Like I said, I came to this evening's comparison session expecting fantastic things from the LVW's. I wasn't disappointed. Fact remains that my modified Hyperion and my humble TMB out performed the LVWs. I saw more stars in them. Isn't that what it's all about? Even if at the extremes the FOV the stars didn't remain pin point, any softening in the Hyperion happened beyond the field stop of the LVW. And, it is not really an area that is used very much when observing. When the object gets so close the extreme edge, you will always move the scope to centralise the object in the FOV anyway. So, for me, this is good enough.
I have no bone to pick with anyone here. I could not be more objective in coming to an observing session. I would not write about what I did not see, especially as I have been seriously considering purchasing some LVWs from what had be written here by yourself and Wavytone - two very learned fellows! I've known Wavy for quite some time too. I consider my purchases very, very carefully, researching as much as possilbe. In the end I saw what I saw. Simple as that. I saw more stars.
29-04-2012, 07:57 AM
Well, when you see something, that's the result! The link I posted earlier of the LVW's was not done by me, it was done by another astronomer, and I thought I would pass that info along.
From what I have saw in the LVW's, the views of stars were pinpoints right out to the edges with superior transmission in my 10" f/4.72 when I did own the 8mm Orion LVW and also tried a 22mm and 17mm LVW.
All three of them showed perfectly tight stars with excellent transmission, albeit a bit of lateral color. I had a 13mm Hyperion and an 8mm Hyperion and the edges showed some edge aberrations. The 13mm has some field curvature, which obviously comes from the mirror and maybe a bit from the eyepiece as well.....not 100% positive on that one.
If you see field curvature in an eyepiece, I believe it is always coming from the mirror no matter what eyepiece you use, ( I think?), but some eyepieces will show this more than others. If you see astigmatism in an eyepiece, it is the eyepiece at fault. I believe the "fishbowl effect" comes from rectilinear distortion.
The LVW's and Hyperions almost have the same apparent field of view.
LVW's = 65°
Hyperions = 68°
As to your post: If it makes you happy to see what you saw, that is the bottom line and that is all that matters! if I or someone else sees things differently, it really doesn't matter! I wish you well, and hope you had a great observing session! Having a 17.5" f/4.5 is a great light bucket to have and I would hand over ALL of my eyepieces and keep just ONE just to own one of those size telescopes! :eyepop:
You sure do have a nice size scope there good sir!
Have yourself a great weekend and may you enjoy thousands more nights looking through that incredible light bucket! :thumbsup:
29-04-2012, 10:02 AM
Not to malign the TMBs & 13mm Hyperions (I have the latter too) nor act the champion of the Vixens but it might be worthwhile doing a comparison and thus test where relative parity exists in the designs.
In terms of the LVW you are comparing a widefield 8 element design against a smaller EP in the TMB. It might be worthwhile doing a comparison of the TMB against a LV or their contempoary incarnation the NLV.
With respect to the LVW's physically the Hyperions, LVWs, Stratus and Saxon widefields all look incredibly similar once you look past the different brand labels/paintwork. I have never looked through a LVW (only physically at them in stores) so I can't comment on their optics but what I like about Hyperions are their modular design and use of the FTR rings.
In my humble opinion and experience the few times you can most often discern some sort of consistently tangible yet significant difference occurs when the atmosphere conditions are really optimal. It is in those odd excellent times that my money bags colleague with his $1000 ZAO-II takes me to the cleaners (with my more modest EP collection) and I can really see differences when we try his EP's on different scopes while trying to keep everything to some degree of parity.
I think for $60 the TMBs are great and for $80-$120 a LV (2nd hand) is great too. However, when I start approaching anything over $300 I start thinking about light green painted letters or Pentax. When money is not an issue - well....... take your pick of the superleagues - I wonder how the new Takahashi widefields fair each at roughly $1000 -OUCH!! - My wallet is already trembling at the thought:lol:
29-04-2012, 10:06 AM
Fact remains that my modified Hyperion and my humble TMB out performed the LVWs. I saw more stars in them. Isn't that what it's all about?
bad galaxy man writes:
Have you seen my post in this thread, comparing a 22mm LWW with a 20mm type II nagler (which is probably an unfair comparison (!!), as this Nagler is one of the very best designs in Nagler's "super premium" line of eyepieces).
The stars seen in the Nagler were noticeably brighter, and I had a fainter magnitude limit with the Nagler.
My impression of the LVW was that the actual light transmission of the LVW eyepiece was noticeably worse than the light transmission of the Nagler, leading to fainter images.
Could it be that the difference between the LVW and the other eyepieces you compared it with is something to do with the relative light transmission of the eyepieces?
(there are definite variations in the coatings, between different eyepieces......I don't think all of the antireflection coatings applied to lens surfaces are equal in effectiveness)
Sometimes, the images are brighter in a simpler eyepiece simply because it has fewer air-glass surfaces to reflect and scatter light!!
The use of a barlow is also a major factor; the fact is that , despite the bad reputation of barlows in some quarters, the narrower light cone of a barlow - at greater effective focal length - often also reduces the aberrations in the star images provided by an eyepiece.
(In my view, the idea of the bad effects of a barlow on views through an eyepiece has become something of an urban myth; an often repeated statement that has become
so-called "truth" due to constant repetition)
29-04-2012, 11:18 AM
Alex, that's pincushion distortion. It is common in eyepieces incorporating the Smythe lens design; essentially it means magnification is not constant across the field and varies radially from the centre.
Hehe I'm not surprised at your other remarks especially transmission, I have noticed that before. You tried the LVW's before at Katoomba and decided they were not exceptional so it' not really news...
As Robert said, there is a huge tradeoff in how much glass and how many surfaces vs field of view, transmission, contrast and image quality. For this reason if you're really serious about smallest objects rather than wide fields the best choice is an eyepiece with only 2-4 elements and few glass/air surfaces. This is why designs such as super-monocentrics, RKE, Plossl, orthoscopic and even Kellner are still useful. I often wonder what could be done if some of these older designs were revamped to take advantage of modern glass types, in particular ED glass.
Choosing eyepieces is an area where there are too many conflicting variables, about which most of us have little or no real information to make a decision. That leaves 'trying before buying' or pot luck. You're fortunate to be able to try alternatives, which was something I couldn't do at the time I bought them (they were half the price of Naglers too).
29-04-2012, 04:57 PM
your comments about using only a 2-4 element eyepiece for certain applications are very very interesting and very worthwile;
though there are some experts who would regard these comments as being highly controversial or questionable.
This sort of argument lead to the idea of a "planetary eyepiece" designed, for instance, to maximize freedom from scattered light in the field that is caused by reflections from multiple air-glass surfaces. For instance, the planetary observers swear that a good orthoscopic eyepiece can give planetary views that are better than those provided by many of the more complex eyepieces.
(Planetary surfaces are a severe test for any combination of optical elements, as the slightest unwanted or excess light that is in the diffraction disk or in the field....can lead to a loss of low contrast detail)
I note, however, that maximizing the contrast between the object and the surrounding field, also can improve the observer's view of a deep sky object. On stellar and non-stellar deep sky objects, the particular Nagler eyepiece that I mentioned had considerably superior contrast to the LVW I tested, to such a large extent that the difference was blatantly obvious even after a few seconds viewing;
but exactly what combination of smaller star images and/or greater light transmission and/or a smaller amount of scattered light, was actually the cause of this noticeably better performance by the 20mm typeII Nagler..... I do not know.
cheers, bad galaxy man
29-04-2012, 10:24 PM
Well... there is an interesting comparison - one which I hope Alex might read too. The first part is comparison of the TMB supermonocentric against other modern high-contrast eyepieces - by Gary Seronik and appeared originally in S&T.
OK, most of you will think it is OK to do this kind of comparison, and those of you using f/4 Dobs with a paracorr will be having warm fuzzy feelings.
But this is followed by a critique by Chris Lord (Brayebrook Observatory) as to what is wrong with the test - starting with why a fast Newtonian reflector is a lousy choice of telescope to do eyepiece comparisons:
But I think Chris Lord was also a little harsh - there are examples of eyepieces having been designed to match the aberrations of specific telescopes - starting with the (now rare) Pretoria eyepieces and RKE's. So in this respect if you have found an eyepiece that YOU like, on YOUR scope, I'd say fine, stick to it !
Now let's look at Alex's test. He used a larger fast Newtonian. Aside from whatever the eyepieces are doing, the diffraction-limited field of view in his scope is tiny - smaller than the FoV of the 13mm eyepieces for sure. Secondly the aperture of his scope means he wouldn't have come anywhere near the diffraction limit from his home. Then there is a question as to vignetting due to the secondary mirror - most fast Newtonians have secondaries that are somewhat undersize simply to avoid them exceeding 30% of the aperture of the primary - and lastly collimation - fast Newtonians are very sensitive to this.
Consequently any conclusions concerning off-axis performance of the eyepiece I would tend to take with a grain of salt because the effects of off-axis degradation due to the scope.
FWIW for a while I used an even more extreme 'scope - a 32 cm f/3.7 Newtonian - and knew all about what was wrong with fast Newts.
If you want tack sharp images at medium to high magnification nothing beats good-ol LONG LONG LONG FOCAL LENGTH, with a small secondary obstruction (none if it's a refractor) and virtually any eyepiece will perform well, apart from contrast.
Ultimately... this is why my current scopes are an f/7 refractor and f/15 Mak, and in some respects I dream of one of these http://www.skylightelescopes.co.uk/. Maybe one day when I can afford a decent mount, and the country house to go with it.
30-04-2012, 10:07 AM
Choosing eyepieces is an area where there are too many conflicting variables, about which most of us have little or no real information to make a decision. That leaves 'trying before buying' or pot luck.[/QUOTE]
This from Wavytone sums it up for me pretty well. Obviously an area where lots of cash wins every time...so while waiting for the long lost uncle's inheritance to turn up it's time to let it all sink in, and for the moment, stick with my GSO plossls and ES eyepieces. Some really good things in this thread thanks all ...wow such a simple question, or so I thought. Wavytone a very nice bunch of scopes from skylight too...also dreaming of a long refractor in the country...
30-04-2012, 11:21 AM
Matthew, yeah, who would have thought from "such a simple question", :lol:!
Wavy's brought up another point - the lack of information on the matching optical properties of different scopes vs those of eyepieces. Newtonians, Maks, refractors, SCT's, these have different properties inherent to them, to not even mention differences between f/ratios in each lot. Different EPs perform differently in each scope type. You will never read in a manufacturer's literature that a particular EP of their's performs poorly in any scope type. It's bull to think that any one EP will be as good in an f/3.7 Newt. as it will an f/15 Mak.
A new RKE which uses ED glass types? I'm in for using it in my fast Newts! 30mm to 5mm, 68 degree FOV, three elements, good eye relief, down to peanut sized, no astigmatism and deals with coma! Brilliant. :love: More like dreaming...
I have the LVW22mm.
On my 10" dob which is a fast scope at 4.7, it performs exceptionally well. Pin point, crisp stars right to the edge. It's one of my favorite eyepieces.:D
Ya should, you in real trouble, this is war mister! :P :lol:
That's actually the first I've heard of a Hyperion trumping an LVW, but as pointed, much has to do with the telescope. I have a fast newt as well, but obviously mirror size etc has to be taken into consideration.
So... the bigger the scope, the cheaper the eyepiece, lol. :P
Sorry, I couldn't resist, forgive me, I mean no harm. I'm kidding, really I am... eeeeeek:face:
The Naglers have got a "coffee tone" colour to them as opposed to XW's for instance that are neutral.
Some people like the colour tone of the Naglers, while some find it annoying as being a false colour tone on stars. I wouldn't know, I don't own a Nagler, but I've read plenty on the "coffee tone" aspect of it.
03-05-2012, 07:31 PM
Suzy, as you know I have 3 Naglers,:D I am looking forward to comparing eyepieces.
I have never as far as I know looked through an XW:( so it should be an interesting exersize :).
04-05-2012, 11:49 AM
I admit, Suzy, that I have never paid much attention to the colour tone of eyepieces.
I have a nagging feeling that certain specific so-called "fully coated" eyepieces actually do have an uncoated air-glass surface that is hiding somewhere inside the eyepiece. A single uncoated glass surface usually reflects 3-4 percent of the light that hits it, instead of transmitting that light;
which, in itself, is probably too small a brightness difference for the eye to notice.
BUT - certain glasses of high refractive index can reflect 6-8 percent of the light hitting an uncoated air-glass surface.
I do think that 6-8 percent could be a visually noticeable loss of the light that ought to be reaching the eye, if one takes into account the fact that the unwanted reflected light is going somewhere into the field, instead of into the image of the object.....thereby leading to a loss of contrast between the light from the object and the light coming from the field (the light in the field has a measurable value)
For a couple of years, I was totally obsessive about visually observing vanishingly faint emission nebulae......and I did find that the various small & not-so-small losses of light taking place in the optical train actually did make a difference to the quality of the views of these very challenging objects that are at or near the fringes of visibility.
05-05-2012, 01:15 AM
:question: I have noticed the ' coffee tone ' in my 8mm Radian , but that dissapares soon after using it , then its real strengths come into play , great eyepiece . The coffee tone does not worry me at all , and I have compared my 8mm Radian with my , 9mm Orthoscopic , 9 and 10mm Vixen Lanthium's and my Baader 9mm ' real' ortho , and they all have their strenght's . :) and I love them all .
On the Nagler coffee tone , I have not seen it in mine , I will look for it now , but it must be very slight .:question:.
05-05-2012, 02:10 PM
LVW for me.
But I reckon ES ep are better value.
Apparently you can tell (so I've read) if you compare it with a neutral tone ep and the warmer tone of a Nagler on the moon.
The warm colour of the Nagler (so I've read) is great for planetary observing as on Jupiter's belts- so there is a plus.
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