I recently purchased a set of Meade Series 4000 Plossl eyepieces for
use in a telescope comparison on planetary performance between a Meade
152 ED and Celestron NexStar 11. I wanted a full range of good quality
planetary eyepieces of the same brand to make my comparisons as fair
as possible. The focal lengths of these telescopes (1370mm vs. 2800mm)
meant that with my existing inventory, I would not have similar design
eyepieces that could be utilized to provide similar magnifications.
As a side effort, I also decided to do comparisons between these simpler
design eyepieces and the premium 2Ē eyepieces I currently own.
This inventory consists of a 35mm Panoptic, and 22mm, 17mm, and 12mm
T4 Naglers. The goal would be to see if the simpler design would outperform
(in absolute terms) the more complex design on a variety of observing
Prior to the purchase of the (used) Meade eyepiece set,
I owned 3 Plossls: A Televue 15mm, and Orion HighLight 12.5 mm and
10mm eyepieces. I started with a 15mm Televue because the resultant
185x magnification in my N11 is the most I can utilize on most nights,
due to seeing conditions. Because there is no 15mm T4 Nagler, I could
not do an exact comparison using the same magnification, however the
TV 15mm Plossl was without doubt, my most used planetary eyepiece.
This is partly due to the fact that it hit the magnification sweet
spot for my seeing conditions, and partly due to the fact that it
just seemed to performed better than the 17mm Nagler in my box on
planetary targets. The Naglers are incredible eyepieces for what they
do, but in fact, I felt that the TV 15mm Plossl was slightly, but
perceptibly sharper and more contrasty when doing planetary observing.
It also didnít ghost or bloom, as the Naglers sometimes do on
The Meade Series 4000 Plossl line has been described
by one reviewer as being an entry-level for premium planetary eyepieces.
In fact, using my Televue 15mm Plossl as a reference, I found the
15mm Meade to be practically indistinguishable from the TV 15mm in
absolute performance. When I would look through one I would think
that it was a tad sharper than the other, until I swapped them. Then
I would think, no, I am seeing the same thing hereÖ There was
some difference in color tone, but it didnít really affect performance.
I also compared the Meade 12.5mm and 9.7mm eyepieces to the Orion
12.5mm and 10mm Highlights. This was harder because seeing conditions
started to affect the ability to make really critical comparisons.
Unfortunately, it appears that I live under a 200x sky.
I could not do exact magnification comparisons. Such
is life. Still, I was able to get within 3mm in every case. In most
cases, the magnifications were close enough that I think comparisons
were valid (35mm Panoptic @ approx. 80x vs. 32mm Meade @ approx. 87x).
I viewed three types of objects: Planet, Nebula, and
open cluster. I will limit my in-depth text to three specific cases:
Saturn, M42, and M35.
In terms of absolute performance The 17mm Nagler was
bested by both the Meade 4000 15mm and Televue 15mm Plossls. Views
were simply sharper with both Plossls. Both Plossls showed a crisp
ring division, and 4 very faint, tiny moons. The details were just
more distinct with the Plossls. One of the four moons was not visible
in the Nagler using direct vision, and only faintly detectable using
averted vision. In terms of contrast, both Plossls also exceeded the
big glassís performance, showing a bit more subtlety in the
banding, blacker background, more distinct planet shadow against the
ring and the Crepe ring stood out just a bit more prominently against
the blacker background between the rings and the planetís disk.
The difference between the Plossls themselves was almost impossible
to see, while the difference between the Plossls and the Nagler were
subtle, but distinct. Finally, the Nagler tended to show a faint halo
around the planet/moon area. This was also noticeable in the Plossls
(Large SCT central obstruction is the cause here, I am sure), but
not to the same degree. In fact, I attribute this halo to be the main
culprit in the Naglerís inability to pick out the 4th moon that
was visible with the Plossls.
Results were similar when comparing the 20mm Meade Plossl
to the 22mm T4 Nagler, though the lower magnification made it difficult
to compare absolute performance because everything just looks so much
sharper at lower powers. In numerous comparisons, and after much changing
back and forth, at every viewing, I judged the Plossls to be superior
to the big Naglers in all aspects of planetary performance, at least
on this one target. I expect that the difference will be noticeable
on other solar system targets to the same degree, and perhaps more
so on Jupiter because of its greater brightness.
The great Orion Nebula, M42:
Here it is harder to do a direct comparison because
of the aesthetic quality imparted by the ultra-wide fields of view
being provided by the premium eyepieces. It is easy to look through
a 35mm Panoptic or 22mm Nagler and be awed by the majesty of this
magnificent nebula. In a recent viewing experience while on a trip
out west under the pitch-black sky over the Nevada desert, M42 over-ran
the field of view of the 35mm Panoptic and provided such an intense
3D like presence, that I almost didnít want to look at it when
I returned home!
Still, in terms of absolute performance, there is detail
available in M42 that doesnít require ultra-wide fields of view.
I have used high powers to poke around this nebula many times. Using
really high powers, you sometimes start to see knots of granularity
and wisps that donít stand out under lower powers. And there
are stars in thereÖ Iíve seen them. Here and there, you
will find extremely faint stars shrouded in the gossamer veils.
Iíll start with the 35mm Panoptic vs. the 32mm
Plossl. Here the difference was very, very small. Mostly it was related
to the field of view provided by wider apparent field of view in the
68 degree 35mm Panoptic. But judging absolute performance, I would
say that the 32mm Plossl did extremely well. While I could see the
E and F stars in the Trapezium in both eyepieces, the F was only barely
detectable in the 35mm Panoptic. The F component was a bit more separated
from the glare of its primary in the 32mm, and therefore, a bit more
noticeable. I donít attribute this to the small difference in
magnification. In fact, all for of the primary stars seemed a tiny
bit tighter in the 32mm Plossl. I had never seriously considered that
anything could really match the 35mm Panoptic in terms of absolute
performance because the eyepiece seems so perfect. And yet I am convinced
that the 32mm Plossl was sharper. Just a tiny bit, but in the end,
sharper is sharper. It was more difficult to judge contrast differences
because of the low powers involved. In this area of comparison, on
this one object, I could draw no conclusion in terms of contrast performance.
Moving up the magnification ladder provided much the
same outcome with respect to sharpness. Viewing the trapezium with
the 22mm and 17mm Naglers, and then changing to 25mm, 20mm and 15mm
Plossls, the primary stars always seemed to be a tiny bit better focused
in the Plossls. Because of this, the E and F stars were more cleanly
separated from their primary stars, but E and F were visible with
direct vision in all eyepieces. There are several field stars around
the Trapezium however, and the Plossls seemed to pull out more of
them. Here and there, using the Plossls, I could detect faint stars
with averted vision that were not visible in the Naglers.
I was able to use the 12.4mm and 12.5mm Plossls against
the 12mm Nagler, but seeing conditions made it more difficult to draw
a conclusion on sharpness. However when roving the nebula itself,
this magnification starts to show distinct variations in the intensity
of the nebula; kind of like a puffiness of a fluffed sheet. I detect
knots and wisps at this magnification that are not visible using lower
powers. Here, the 12mm Nagler was perhaps equal. Once again, the much
larger field of view of the Nagler provides a challenge to making
a valid comparison. You are seeing more background sky glow in the
bigger field of view, which hurts contrast, but at the same time,
the scale of some of these knots and wisps makes them overrun the
smaller field of view of the Plossls. Consequently, they tend to be
more recognizable in the 12mm Nagler. In ABSOLUTE performance, I would
say that the simpler eyepiece did show better contrast, but the 12mm
Nagler is probably the best eyepiece for me for this particular application.
Open Cluster M35:
Once again, the Plossls bested the more complex Naglers
and Panoptic in absolute performance. I could detect stars in the
simpler design that were only visible using averted vision in the
more complex eyepieces, and I could see stars using averted vision
in the Plossls that were not visible at all in the Naglers. In all
cases, the stars were a bit sharper in the simpler eyepieces.
A single Planetary Nebula:
In faint, fuzzy observing, I have not done as much of
a comparison. Just last night, I did slew my N11 to a faint planetary
in the Orion area (I canít remember which one, sorry). In summary,
once again, the Plossls seemed to show a brighter nebulosity against
a darker sky background. I could also use more power with the Plossls
on this target. In fact, I could barely detect the nebulosity in my
17mm Nagler. I had the Nagler eyepiece in when I slewed, and when
the scope stopped, I didnít detect the nebulosity at all. When
I changed to the 15mm Meade Plossl, I just barely caught it to the
northeast of the center of the field of view. When I put the Nagler
back in, I was able to see it with the Nagler as well, probably because
I knew where not to look (averted seeing joke, get it?).
In almost every comparison I made, the simpler eyepieces
delivered better absolute performance than the MUCH more expensive
Naglers and the lone Panoptic in this test. I donít want to
comment on the less tangible, more subjective attributes of the incredible
Nagler design. Let it suffice to say that I am not going to sell any
Naglers as a result of this comparison. If I just want to stumble
around the sky, or when some objects sit in a particularly beautiful
field, I still think that the Naglers provide a stunning experience.
The ability of the Nagler to frame objects in longer focal length
telescopes makes them particularly desirable, and while it may ultimately
be marketing hype, the spacewalk affect is quite seductive in terms
of its contribution to the overall observing experience.
I will have to say that I can no longer ignore the difference
in performance between the simpler Plossl design and the big, premium
eyepieces. In fact, in the time since I have acquired this set of
Meade Super Plossls, I find myself selecting them for more critical
examination on many objects. Now more than ever, I am find that the
better detail and contrast I can see using the simpler design DOES
make it easier to just not notice the more restrictive field of view,
as compared to the premium eyepieces I own. In terms of absolute performance,
I now realize that it is tuff to beat a good Plossl.
Also, in the past, I have recommended that everyone
should try at least one premium 2Ē eyepiece. Now I am not so
sure. At their increasingly high costs, the difference between a FULL
SET of quality Plossls and a single Nagler starts to look less appealing.
Also, a bigger or better telescope, with a smaller selection of quality
Plossls would perhaps be a better use for the money. Really. Especially
when you consider the additional cost for high quality 2Ē diagonals!
Almost all of the differences in the observations I
made in this comparison are probably greatly exaggerated because of
my local seeing conditions and by my telescopeís large central
obstruction. I believe that the affect of these two factors is magnified
by each successive refraction or reflection in the optical train,
collimating in an orgy of reflections and light scatter in the numerous
air-glass surfaces of these complex eyepieces. Yes, these eyepieces
use the finest optical multi-coatings available, but nothing eliminates
these reflections; they just reduce them. Multi-coatings on the three
or four extra PAIR of air-glass surfaces in these ultra-wide view
eyepieces arenít going to help them escape from the laws of
physics. Popular books on the subject of star-testing and telescope
design tend to treat everything in terms of optical aberrations in
the primary optics, or in theoretical examinations of ray tracing.
It is my theory that the successive light scattering of all of these
surfaces in the complete optical train all add up to make the differences
in eyepiece performance more detectable as apertures increase. Under
steady sky conditions, the differences I noted in my observations
may be less readily apparent as stars can be more closely focused
into airy disks, also resulting in much less contrast reducing scattered
Large apertures with large central obstructions are
probably going to show the differences between these eyepieces more
conclusively than doing this test with smaller aperture, high quality
refractors. I recently purchased a Televue Genesis, and I am eager
to see how the Plossls stack up to the more expensive eyepieces when
used with a premium 4Ē refractor. It is my guess that the differences
wonít be quite as noticeable on the small, unobstructed aperture.
Do you want me to tell you how it turns out???