Figure 1. The Celestron 114 Firstscope on its equatorial mount. The
Celestron name is in red and is painted on, i.e., it is not a decal.
Note the size of the optical tube in comparison to the mount.
This review, like many
other reviews, is of a used telescope with unknown history. This
particular example (shown in Figure 1) was
purchased from a pawn shop sight-unseen and had previously suffered:
there were scratches and dents on the optical tube, the optics
were quite dirty, and some screws were missing. Consequently, this
particular example may not be representative of this model.
Figure 2. The specifications are given on this label. The “f1” on
the label is likely meant to refer to “focal length”.
The scope is actually an f/8.
The only documentation supplied is the label shown in Figure 2.
The 910 mm focal length is a bit unusual (most are 900 mm) and helped
to identify the scope. An advertisement in a 1996 issue of Astronomy
list two variations: the Firstscope 114 and the Firstscope 114 Deluxe.
The deluxe model replaced two 0.96” eyepieces and a 2X barlow
with two 1.25” eyepieces and no barlow. The example reviewed
here is the deluxe model. The same ad gave the price as $250US (one
assumes for the non-deluxe version), which corresponded to about
$375 CND. The deluxe model would likely have been over $400 CND.
The mount appears to be identical
to current “EQ2” equatorial
mounts that are popular on low-cost telescopes. However, instead
of aluminum legs, this example has wooden tripod legs that are of
As received, the equatorial head had a great deal of slop in it
and was not usable. In order to correct this problem, the mount was
disassembled (see Figure 3). Most of the moving components were covered
in a very thick and sticky grease that was about the consistency
of gluestick. One assumes that the purpose of this grease was to
remove some of the play in the mechanical components.
Figure 3. Photograph showing the mount disassembled for inspection.
In order to polar align the telescope, the mount allows
motion about the vertical (azimuth) axis. This axis had a great deal
of play in
it and allowed the telescope to wobble during normal use. Figure
4 illustrates that this axis comprises a conical stub shaft that
fits into a similarly shaped hole. The black paint on the mating
surfaces of the two pieces is very unusual since it quickly wears
off and mixes into the grease. The clearance between the shaft and
hole was measured using feeler gauges, shown in Figure 5, and was
found to be 0.51 mm (0.020”). The base was assembled and the
corresponding wobble measured as shown in Figure 6. The clearance
is 0.76 mm (0.030”), which corresponds to a wobble of plus
and minus 0.55 degrees.
Figure 4. Photograph showing how the mount’s base fits
Figure 5. Photograph showing measurement of the clearance between
the shaft and hole.
Figure 6. Photograph illustrating how the wobble was measured using
feeler gauges. In this case the feeler gauge is 0.76 mm (0.030”)
There were a number of other problems with this mount. For example,
Figure 7 shows that the mount is made from very thin aluminum that
has broken once. To lock the right ascension axis, a steel screw
presses against the RA gearshaft. Figure 8 shows how the softer aluminum
gear shaft is being worn by the much harder steel screw. The RA slow
motion control was very stiff in part of each rotation and was likely
due to a out-of-round worm gear. In addition, the counter weight
shaft is locked in place by three screws as shown in Figure 9. These
screws are destroying the threads on the declination axis as well
as their own threads.
Figure 7. Photograph showing the underside of the mount. The casting
is very thin aluminum (about 3 mm at green arrows) and has already
broken (red arrow).
Figure 8. Photograph showing the cast aluminum right ascention gear.
The red arrow is where the RA lock screw is scoring the shaft,
and the green arrow shows the resulting aluminum filings.
Figure 9. Photograph showing how the counter weight shaft is
held onto the declination shaft. To prevent loosening, three screws
are threaded up against the declination shaft’s threads,
which are being destroyed (green arrow).
The optical tube
The tube is made from
very thin aluminum, which dents rather easily. However, it is fairly
light weight. One quirk is the manner in
which the secondary mirror is supported (see Figure 10). It is
held by a single plastic arm, instead of the usual spider, and
its location cannot be adjusted. Another quirk is that a clip covers
part of the secondary mirror.
The tilt of the secondary mirror is adjustable via three small screws
shown in Figure 10. The primary mirror has three spring-loaded thumb
screws for adjustment and these function quite well. The focuser
is made of plastic and uses two screws to lock the eyepiece in place.
A small finder scope is made of plastic and is heavily stopped down.
It has an adjustable focus. Its mount uses two rings and six screws
to securely hold the scope in alignment.
Figure 10. Photograph showing the single arm secondary mount. The
green arrow shows a clip that obscures part of the secondary mirror.
This telescope accumulated a fair bit of dust during its stay at
the pawn shop.
The two included eyepieces
shown in Figure 11 are the deluxe ones with 1.25 inch barrels.
Figure 11. Photograph showing the two 1.25 inch eyepieces included
with the deluxe model. Fit and finish are evident.
At some point in the past the finder scope
had been bumped, which caused the thin aluminum optical tube to
dent. Consequently the
finder scope could not be properly aligned. In any event, the
finder scope was too small to be useful.
Although the mount performed much better after being cleaned and
adjusted, polar alignment was out of the question. Two lock knobs
allowed the telescope to be slewed by hand. Once aimed, tightening
these knobs caused a change of direction and required correction
with the slow-motion controls. Once tightened, the scope could easily
be rocked a better part of a degree. Turning either slow motion control
induced an annoying shake.
The focuser is a bit stiff but was otherwise acceptable. Unfortunately
any attempt to focus caused large-amplitude low-frequency oscillations,
which tended to induce motion sickness.
The telescope was aligned with a laser collimator before visual
testing. Optical performance was acceptable (for a telescope in this
price range) with no gross defects. The clip covering part of the
secondary mirror was visible in out-of-focus images.
Discussion and Conclusion
a telescope, an important criteria is the overall design and construction
of the instrument. Ideally no single component
will be the limiting factor of performance. For example, in a high-end
telescope every component will be of the highest quality and observing
will never be limited by the quality of the instrument, only by
the inherent resolution and viewing conditions. Entry-level telescopes
are a different matter: ideally the telescope will be easy to use
and the observer won’t be frustrated by mechanical problems.
Optical quality is less of an issue because beginners are usually
happy with less than perfect optical performance -a good thing
since they often don’t know how to collimate their scopes.
With this in mind consider the present telescope and its components;
the optical tube, finder, focuser, tripod, and mount.
On average the quality of the optics is acceptable for a telescope
in this price range. The secondary mirror collimation screws are
better than average. However, no special design features have been
included for beginners, e.g., knurled thumb screws instead of allen
head screws. In contrast the primary mirror collimation screws are
nicely done and easy to use. The focuser is a bit stiff but is otherwise
acceptable. The secondary mirror support is rather flimsy and can
be easily moved around during collimation. Any misalignment in the
position of the secondary mirror, for example bending the support
arm by pressing too hard on the mirror’s lock screw, will be
difficult to correct. The optical tube is very easily dented (this
example had many). In general the optical tube is very delicate.
Many companies tend to put poor quality finders scopes on their
products and this one is not an exception. A simple unity (straight
through) finder would likely be more use.
The wooden tripod legs are simple to use and work well. The only
problem is that the spreader bar is held in place with wingnuts and
is difficult to install. Three screws need to be removed in order
to transport the scope, otherwise various components tend to bend.
The EQ2 mount is by far the limiting component of this instrument:
the relatively light weight optical tube completely overwhelms this
mount. After a careful clean and adjustment, the mount still had
a wobble close to one degree and is frustrating to use. The wobble
is inherent in the design and cannot be easily corrected. In addition,
the design has resulted in some of the components wearing rather
In conclusion this telescope is marketed towards beginners and comprises
an acceptable, although delicate, optical tube assembly coupled to
a mount of questionable quality.
Celestron Firstscope 114 Review Follow-Up
After posting this review I received a few emails claiming that this
telescope must have been abused. Given the unknown history of this
particular telescope, we can never know if it was abused or merely
well used. However, this summer I made use of an opportunity to visit
three telescope stores: one in Montreal and two in Toronto. On display
were many entry-level telescopes. Although these were branded by various
different manufacturers they all used the same (EQ-2) mount reviewed
here. This allowed a comparison of a number of brand-new EQ-2 mounts
to one well-used one.
In general the design of all the EQ-2 mounts appeared
to be identical. In addition, the mounts seemed to have been manufactured
with similar machining tolerances. The new mounts contained the same
thick and sticky grease present in the reviewed example.
As for purchasing advice: if you are considering a telescope
that uses this mount design then it is recommended that you read this
review very carefully and then inspect one in the showroom. Take your
time moving the scope through all its axes of motion paying attention
to how much play there is. Don’t be fooled by sticky grease:
the play is still there - it just slows down the wobbles. Most importantly,
try a high-end mount so you see how solid and play-free a mount should
On a personal note, the telescope reviewed here has
caused a certain amount of unease. It is of no use to me, but I can
not sell it to an unsuspecting buyer knowing that the mount is all
but useless. In the end I may have to sell it as an optical tube assembly;
throwing the mount in the garbage, and taking a financial loss. At
least I didn’t pay the new price for it.