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GTO Zoom |
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REVIEW ARCHIVES Refractors Barlow
Lenses LINKS FAVORITE LINKS NASA
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The Review After having my 10” LX200, ETX-125, and my DS-90 refractor telescopes for a year now, and also going on an “eyepiece binge”, I bought this little zoom from Gary Hands of Hands-on-optics. I wanted to try a zoom to see if I liked zooms at all and this was an inexpensive way to try one. If you want to see how many eyepieces I have collected in a year go to my web page @ http://home.socal.rr.com/hotweb/ Needless to say I have used and looked
through a heck of a lot of eyepieces.
When I got this zoom I did not expect much as it is the cheapest
zoom you can buy today. The first night with this zoom was in
my 90mm refractor. The seeing
conditions were very good and stable. With it set to 22mm the view was
like looking through a drinking straw YUCK!
But as I racked the zoom in, the FOV gradually opened up.
From about 12mm to 7.4mm the FOV was very respectable.
Comparing the FOV to standard plossls, at 7.4mm the FOV is larger
than my 6.7mm Meade plossl. At about 12mm the FOV I estimated at about 50 degrees FOV and
going up from about 12mm the FOV really starts to close up (22 = an
estimate of about 38 FOV). I
would say this EP is a good value from 12mm to 7.4mm. It is advertised at
63 FOV at 7.4 mag and I would say that is about right.
However it has a small eye relief (about the same as a Meade 6.7
plossl). I do not know how
much and since I don’t wear glasses I did not make a mental note.
If you wear glasses this may be a problem. If you can use a 6-7mm plossl then you should be OK.. This FOV is exactly what I wanted and
expected. I wanted to try a
zoom on planets so I could “dial in” the perfect max magnification for
the seeing conditions. In my
opinion you do not need a large FOV on the planets.
And in fact my SWA and UWA eyepieces experience “glow” or
“ghosting” around the planets, which was not desirable.
My Plossls do not experience this glow so I knew I needed something
“standard” for the planets. The ShockerWhen I looked at Jupiter at full mag
of 7.4mm I could not believe how good it looked!
I said to myself it has to be the good seeing conditions that night
as the view was very sharp, nice contrast, and I could not get enough! Moving the scope to Saturn was the same effect.
The Cassini division was super sharp and clear and bands on the
planet were easily seen. This was just too good to be true so
out came my Radian 8mm. I
popped it in and studied the view. Hmmm
there is that hallow I hate! But…
hmmm….. I could not see as
much of the cloud bands on Jupiter! Clarity was the same but contrast
seemed to not be as good. What
this can’t be? How the heck can a $50 zoom be out performing my $240
Radian 8? This just can’t
be. Popped the zoom back in
and yep the view was better. Back to Saturn again to compare.
Same thing. The Radian
8 is just as sharp on the Cassini division but cloud bands are much less
visible. I was starting to wonder if my Radian
8 was defective? The next day
I took this zoom and the Radian 8 down to my local scope shop (Scope City)
to have others look through them and to check out my Radian. The guy at my
local Scope City is very knowledgeable and has been using scopes for
years. We compared my Radian
with another from the store. Granted it was daytime but the store model looked the same as
my Radian and the guy in the store said he did not think there was a
problem. Then I had him look
through the zoom. He was
impressed especially when I told him the price.
Again daytime but a trained eye gave a good initial head nod. He
told me to try this test again in my 10” LX200 as the cheaper 90mm
refractor could be “tricking” my eyes. Next night and out comes the LX200.
Another very crisp, clear, and steady night. I performed all the
tests as I did the night before. I just wanted to cry! Again this zoom outperformed the
Radian. Now I could not get
completely to the 7.4mm as the seeing would start to breakdown on a 2500mm
scope (338x) but at 8mm (312x) seeing was OK with some slight waves. It
was good enough to compare the two EPs when seeing would “pop in”. OK, OK… maybe the Radian would do
better at DSOs. Off to Orion. This comparison was much harder.
With the Radians eye relief I had a hard time. It seemed SLIGHTLY better than the zoom but was I just
enjoying the eye relief? Hard
to say but at least it made me feel better about the $240 Radian. Weeks later I was at a star party and
I wanted to see what others thought.
Seven people looked and gave their opinions.
Three said they did not see a difference and the others said the
zoom was better than the Radian on Jupiter. All said the eye relief was
way better on the Radian. Two of the folks said they were going to order
this EP for $50. Bottom Line I thought that with all the extra glass and moving optics in a zoom that they would not be a good performer. My comparison shows this was a wrong assumption! This is an incredible eyepiece for the
price. What I have decided now is that this zoom is a keeper for planetary
work PERIOD! I will keep my
Radian for DSOs and the better eye relief. I highly recommend you give
this EP a try. From about
12mm down to 7.4mm is where this EP is useful.
It’s FOV about 12mm and up it just too narrow so don’t count on
liking it above about 12mm. Gary offers a full refund so if you don’t
agree with what I found you can return it. Now that I determined that a zoom is a
useful eyepiece because you can “dial in” the perfect magnification
for the seeing conditions, I am going to invest in a more expensive model
and try it out (remember I am on a EP binge!). The cloudy nights web site
reviews indicate the Lieca zoom to be the best choice.
It has a better FOV than this zoom (68 at 7mm) but costs $300.
Hmm I wonder if 5-7 more degrees of FOV is worth $250 extra? It
also has better eye relief. I
just bought one and it is on the way so I will let you know.
I will also let you know how the Lieca fares against this zoom and
my other non-zoom EPs. Submitted by Bob White
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