Eyepiece reviews
Pentax XL
If you are fortunate enough to have bought a Pentax XL before Pentax
inexplicably stopped producing them, you'll know that they were among
the very best eyepieces available. For wearers of glasses
they were the best,
with a generous 20 mm of eye relief. The apparent field of view
is 65 degrees on all models I have seen, although I believe some of the
longer focal length models have a reduced apparent field. In grid
tests, we have found them to be free of visual distortion virtually
right to the edge, and they consistently provide bright, sharp
images. They have a metal eyecup that can be screwed to suit your
brow or glasses, and this is far better than the usual foldable rubber
eyecup. Coatings are superb. The weight of the XL is a
pain, because my ETX 90 RA's drive can't handle it, and swapping
between these and lighter eyepieces on my 200 mm F6 Newtonian involves
resetting the balance of the scope. My own XL is a 7 mm, and I
now consider it a treasured hierloom to be bequeathed to one of my
children who shows an interest in astronomy. What were the people
at Pentax thinking of when they discontinued this line of
eyepieces? I haven't seen the replacement XO and XW models, and I
don't feel like taking out a mortgage in order to buy one.
Meade series 3000 Plossl
I've enjoyed a 25 mm Meade series 3000 Plossl for many years. It
has 50 degrees of apparent field, and generally good image correction
towards the edge. Eye relief is approximately a generous 20 mm,
and I've taken to using it with 2x and 3x barlows with my ETX in
order to retain the eye relief at higher magnifications. It's a
solid performer, and again it is hard to understand why Meade has
discontinued the line. Wearers of glasses should note that eye
relief of Plossls decreases with focal length, and Plossls with focal
lengths smaller than about 12 mm very uncomfortable.
Meade super Plossl
My ETX arrived with a "Super Plossl" 26 mm eyepiece, that was reputed
to be better than standard series 3000 Plossls. Personally I couldn't
see any difference in image quality, and the much reduced eye relief
was a pain for me as a wearer of glasses. Even those with no
glasses commented that they preferred the series 3000 25 mm. I
was happy to be able to sell it and keep the series 3000.
Meade 3x shorty barlow
Meade sells specialised shorty barlows for use with ETX telescopes, and
they are well coted and provide clean, crisp images. I use mine
not only with my ETX, but with my ToUCam and 200 mm F6 Newtonian to get
great planetary images.
Vixen Lanthanum LV
If you have a telescope with a motorised equatorial mount, don't be put
off by the 40 degree apparent field of view of the higher
powerVixen Lanthanum eyepieces. I have purchased a 4 mm and a 6
mm, and they are my eyepieces of choice for planetary viewing.
Each eyepiece has 200 mm of eye relief, and they are parfocal.
For those who are budget-conscious but want superb correction and good
eye relief for higher powers, these are the best choice. Coatings
are great, and the rare-earth Lanthanum glass results in an
"Apochromatic" eyepiece that can complement great telescope
optics. Rubber eyecups are a pain to have to turn down all the
time, but this isn't a major impediment. Through my 90 mm ETX or
my superb 200 mm F6 Newtonian, I have enjoyed some of my very best
views of planets with Vixen Lanthanums.
Vixen Lanthanum LVW
For lower power views, if you can't locate a secondhand Pentax XL and
like me you think the new Pentax XOs and XWs are over-priced, Vixen
Lanthanum LVW wide-field eyepieces are a good alternative. I own
a 17 mm, and in grid tests it runs a very close second to the Pentax
XL. Images are very slightly less sharp near the edge. In
all other respects, this eyepiece is a fabulous, well-corrected Apo,
and I'll never give it up. It combines the 20 mm eye relief of
Vixens LVs with 65 degrees of apparent field. Like the Pentax XL,
it is too heavy for an ETX 90 RA's drive.
Celestron XCel
Sadly, I bought an 8 mm Celestron XCel sight unseen. It is very
well finished, comes in a nice plastic case, and the orange coatings
look great. The 55 degree apparent field was a magnet, as well as
the 20 mm eye relief. Unfortunately, these good features are
heavily compromised by an enormous amount of "kidney beaning"; at every
angle I hold my eye I see some blacking out of some part of the
field. This might be ok for viewing planets, but this eyepiece is
useless for anything else.
Celestron Shorty 2x Barlow
For the low price, the Celestron 2x shorty barlow is a solid
performer. I've enjoyed many great views by combining it with my
Meade series 3000 Plossl. The coatings are good, and there is
minimal image distortion. I've used it with my ToUCam and Meade
ETX 90 to get some great images of Mars.