I'm primarily a binocular observer. I find it very satisfying and relaxing
to observing the sky, and deep sky, with relaxed both-eyes-open upright binocular
viewing. However recently i've been thinking i wanted something with a bit
power to supplement my binos in the field. I really didn't want to spend too
much money. And i didn't want to replace the binos, just add to their enjoyment.
I decided to buy a small refractor and chose the AstroView 100mm f6 from Orion
Telescopes. I purchased the optical tube only without mount
for $249. This includes 2 eyepieces (25mm and 10mm Sirius Plossls), a mirror
diagonal, and 6x30 straight-through inverted finder scope.
Less than 48 hours after placing my order on the Orion website the scope arrived
at my work place via FedEx 2 day service! On my lunch break i took my new toy
home. These are my initial impressions.
The scope comes double-boxed and securely packaged from Orion. An instruction
booklet written by Orion is included as well as the "student" edition
of TheSky astronomy software on CD. I didn't really need the instructions but
they are plain and well written and include basic assembly, how to calculate
the power of eyepieces, some tips on observing, as well as how to collimate
the scope. (More on that later.)
The only real assembly involves mounting the 6x30 straight-through finder and
installing the star diagonal and inserting an eyepiece. The finder uses a simple
two thumbscrew design pushing against a spring loaded 3rd bearing point. Much
easier to align than the traditional dual ring finder mounts that have 3 thumbscrews
in each ring. I happen to like a straight through finder although i may upgrade
to one of the "red dot" finders eventually.
The scope is quite nicely finished with a glossy black main tube and texture
painted dark gray aluminum castings for the lens cell and focuser assembly.
The 2 inch to 1.25 inch adapters are all aluminum. One of the adapters is also
threaded to accept a camera T-ring. A 4 1/2 inch deep metal dew shield comes
attached to the front of the scope. Passing a magnet over the scope it appears
most everything is aluminum. However the internal baffles seem to be steel as
they attract the magnet when it's passed along the tube. The only plastic parts
are the focusing knobs and the little dew shield on the finder scope. All other
parts are metal.
The 2 inch rack and pinion focuser seems quite smooth although nothing like
a top of the line unit. It showed no tendency to shift focus either. The focuser
supplies 3 inches of motion. I found with the star diagonal installed that eyepieces
focused on infinity with the focuser racked out about 1 inch. There is also
a focus locking thumbscrew.
Orion includes a collimation eyepiece and instructions in the booklet on how
to use it. I popped it in and had a look. Alignment was dead on! Very nice.
(It's nice for once not to have to worry if TWO optical tubes are aligned or
not. Ah, the simplicity of a telescope.) If collimation is required the lens
cell has three push-pull adjusting screw pairs around the cell. A small Phillips
screwdriver is included for one set of these screws but you'll also need an
Allen wrench for the other set. (I thought it odd the screwdriver was included
but not the Allen wrench.)
I set up the scope in my driveway on my sturdy Bogen tripod and put in the
25mm (24x) eyepiece. The scope has an aluminum mounting plate tapped for a standard
photo tripod thread. Since it was daylight i focused on a mountain peak about
2 miles away. The image was very nice. Quite crisp and i noticed no color fringing.
Shrubs and boulders on the peak were very clear. The field was sharp right up
till maybe the outer 10% where it got just a bit soft. Putting in the 10mm eyepiece
(60x) i was pleasantly surprised to see the eyepieces are parafocal requiring
no refocusing. Being a warm day heat currents were very noticeable with the
high power eyepiece so i couldn't really tell about its sharpness. The scope
balanced quite well on the tripod for low angle viewing. When viewing near zenith
the scope tended to want to fall backwards. This is not the fault of the telescope
but of my simple tripod mount.
Something i found interesting was the main cell lens cap. It has a removable
center cap giving a 2 inch aperture. I assume this is for use when viewing a
bright moon or maybe to improve sharpness when seeing is bad.
The OTA alone weighs 6 pounds. With finder, diagonal and eyepiece the scope
is just under 7 pounds. Overall length from dew shield to outer corner of star
diagonal is 27 inches when the focuser is fully retracted.
I should say up front that i'm not an expert on evaluating telescopes being
that i'm more accustomed to binoculars! I'm also a lot more familiar with dim
fuzzy objects and with the bright moonlight most of those were not looking very
I started with Venus in early twilight, about 6:30pm local time. Using the
25mm Plossl (24x) Venus was a very nice little crescent. When centered in the
field i noticed no colors. Just a white crescent. There was still quite a bit
of thermal interference so the planet wasn't completely steady.
Bright stars for the most part were sharp but not pinpoints and tended to show
little spikes at times. However i'm quite sure this is mostly the fault of my
eyes. I see similar spikes in binoculars. Also, with the telescope, when i rotate
my head around the eyepiece the spikes move with me. However stars through the
telescope did seem sharper than through my Fujinon 16x70 binoculars for the
When bright stars were centered in the field and centered in the eyepiece i
didn't notice any spurious colors at 24x. Arcturus was orangish and Vega white.
(At 60x Vega did show purple fringing.) I did see a bit of violet color when
i shifted my eye off center even at low power. If i moved my eye to the right
in the eyepiece i'd see a bit of violet on the left side of the star. And visa
versa if i moved my eye to the left. I noticed the off axis colors a bit in
both the 25mm and 10mm eyepieces. But again, with stars centered there was very
little (if any) color fringing noticed at 24x.
Mizar resolved nicely at 24x. At 60x it was quite wide. With my 16x70 binoculars
i can just split the pair.
The wide components of Epsilon Lyra were of course easy. And at 60x i could
just detect that each star was a bit oblong... one perpendicular to the pair,
the other parallel. That's something i certainly can't see in binoculars. Also
in Lyra the Ring nebula M57 was interesting. My 16x70 just shows a little star-like
ghost. The AstroView at 24x held the planetary quite well. At 60x it was a cute
little bagel with a nice hole in the middle.
M11 in Scutum resolved into a lot of stars at 60x. Could even see a bit of
a dark lane through the cluster. Didn't think i'd be able to see that with the
moonlight. The Fujinons only resolved the single bright star.
Now over to the almost full moon. And i feel i need to comment again that i'm
even less a lunar observer than i am a telescope user so take these comments
with that in mind. The moon is bright! (And i'm a dim fuzzy guy.) With the moon
centered in the field and centered in the eyepiece i saw no colors around the
outer limb. However, similar to my observations with bright stars, if i shifted
my eye a bit to one side i did see some violet/purple fringing on the opposite
lunar edge. I noticed this with both supplied eyepieces.
One more object i viewed tonight was the open cluster M7 in Sagittarius. I
must say it was gorgeous. Using the 25mm Plossl (24x) the cluster was beautiful.
Even with the almost full moon. I noticed little associations of stars that
i'd never noticed with binoculars. Very nice. I'm afraid i may be becoming a
bit of a refractor convert. But then again binoculars are just dual refractors
so i guess i shouldn't be that surprised.
In summary i would say the lens performed very well at the relatively low powers
i employed. I'm certainly pleased with the views and quality of this scope.
On the other hand, i don't really have experience with many (or for that matter
any) high quality refractors. But i'm very happy with the scope and i'm very
much looking forward to trying it out under some dark skies... alongside my
binoculars of course.
|* Peer Review:||The peer review process was a voluntary procedure in which the author’s article undergoes a detailed review by a body of his/her peers. The articles are checked for veracity and accuracy.|
|* First Impressions:||A quick look at and through the equipment, not to be confused with an in-depth or detailed evaluation that’s taken place over a period of time.|