Joe Bergeron's
Astronomy
Equipment
Reviews
Televue
Pronto
Questar 3.5"
Starsplitter 10" Compact
Coronado PST
Denkmeier II Binoviewer
Losmandy G11 Mount
Desert Sky Astro DSV-1 Mount
Telrad
Rigel Quikfinder
Televue Quickpoint
Televue Starbeam
Astro-Physics Maxbright Diagonal
Televue Radian Eyepieces
Televue Nagler Type 6 Eyepieces
Stellarvue F50 Finder
VERNONscope Brandon 94mm Refractor
78mm f/6.5 Jaegers Refractor
14.5" Sky Designs Dobsonian
The
TeleVue Pronto, now discontinued, was a sweet, beautiful little
telescope. I
owned and sold two of them. They suited me well, being very solid
and well-made. The lenses gave some of the finest star images I've
ever seen. However, it should be noted that by no means was the Pronto
an apochromat. They showed plenty of color on the moon, bright stars
and
planets, and also daylight objects (despite Sky & Telescope's
review of the optically identical Ranger, which claimed otherwise).
TeleVue didn't represent the scope as an apochromat, and I
considered it a simple achromat. The false color on the planets was the
only
thing about these scopes that diminished my enjoyment of them. If I
were to get something similar again I would prefer the new
apochromatic TV 76.
I used my first Pronto on a TeleVue Gibraltar mount, which was certainly up to the task, but was not overkill in my opinion. The second one sat on a Manfrotto tripod and a TeleVue Telepod head. The Pronto balance plate accessory was a necessity in both cases. The scopes didn't balance worth a darn without it.
The best way of describing my results is to quote from a letter I wrote to Al Nagler about the older scope:
"I recently had my first chance at extended use of the Pronto beneath truly clear, dark, summer skies, with the Milky Way arching high overhead. With a 35mm Panoptic and UHC filter in place, I went hunting for the huge nebulae that don't fit in the field of my larger scopes. I was very pleased by the results. The entire field of Gamma Cygni was a bright intermix of complex light and dark nebulae. These very faint IC objects formed a stark mottling of darkness and light.
I then moved a bit to the north for the finest view of the North America nebula I've ever had. At 14x, it and the Pelican were perfectly framed. The North America was very stark and bright and looked like a ghostly map of the continent, albeit mirror reversed. The Pelican was much fainter, but still obviously there, and quite detailed. Even more impressively, the whole surrounding area was filled with large star clouds and masses of nebulosity, stuff not even plotted in Uranometria. These are things you normally see in deep wide-field photographs of this region, but you don't expect to see them visually. Peering around at all this faint, glowing stuff gave me a curious feeling of intimacy with the Galaxy, of seeing things that are supposed to be hidden or invisible.
I was able to spot the planetary nebula IC 1295 in Scutum, next to the bright globular NGC 6712. M33 was an easy, forthright oval using the 22mm Panoptic, scarcely living up to its reputation of being a challenging object. I also found that I could partially resolve the brightest globulars like M13 and M22 at high powers.
When you combine the Pronto's ability to provide crisp planetary views with its excellent wide-field performance, it becomes a very versatile little package which would be hard to match with any other portable instrument. For an astronomer who needs both extreme portability and pleasing views of all major classes of objects, Pronto is an great choice. The mechanical qualities are also outstanding. Every time I tweak or focus mine I'm reminded that I'm dealing with a high-quality piece of hardware. I'm happy to own one."
Besides that memorable session, I had a lot of fun looking at comets Hyakutake and Hale-Bopp with the Pronto. They were magnificent for scanning the southern Milky Way from dark sites. When I compared the Pronto to the Questar, I found that although the image was somewhat dimmer in the Pronto, planetary detail was about the same, presumably because of the Pronto's greater contrast. Overall, it was a more versatile scope than the Q for visual use because of its potential for very wide fields. It was also one of the prettiest scopes I've ever owned. In its simple, clean, functional way, I found it the aesthetic equal of the Questar. The Pronto was also the perfect companion for the 40mm or 60mm Coronado SolarMax H-Alpha filters, as I discovered while I was caretaker of my former astronomy club's 40mm SolarMax.
I'm
pleased (and surprised) to find myself owning a 3.5" Questar.
It's a miniature optical and mechanical marvel, the equivalent of a
driven, fully mounted long-focus 3" refractor in a case just a bit
bigger than a lunch box. I've admired these little jewels since I was
a kid, though I overestimated their potential, encouraged to
do so by Questar's extremely optimistic advertising. For example, my
first serious telescope was an 80mm f/15 Jaegers refractor. I always
assumed a Questar would be a step up, since not only did it have a bit
more
aperture, it was a Questar, not some $150
home-assembled scope. Now I'm not so sure.
In 1976 my mother shocked me by actually buying one of the expensive little things, mostly for use as a birding scope. But she never used it all that much, leading her to give it to in 1993. This is certainly the only way I would ever have owned one!
I once did a limiting magnitude test on the Q, coming up with a respectable figure of 12.6. Although I wouldn't use it to probe the dimmer reaches of the NGC, it gives surprisingly good views of brighter deep sky objects, resolving M13 and a few other globulars fairly well at high powers. The hoods of Comet Hale-Bopp showed up well. Besides its limited light grasp, its main drawback as a deep sky scope is its inability to give a wide field of view. You can't get much more than a degree out of it. It's a nice scope for quick looks at the moon, sun, and planets, though this can be hindered by the long cool-down time (mine has a Pyrex mirror). As a quick moon-viewer on a bright evening it's a good companion. Lunar images hold up well at over 200X. Planetary detail is abundant enough to give some idea of what's going on, though I doubt many ALPO observers rely on them. My 92mm Astro-Physics Stowaway refractor completely outclasses it on the planets.
Nice as it is, I wouldn't recommend a Questar to anyone to whom money means much of anything. If you can afford the price without wincing, it's the best extremely portable complete telescope available. But at over $3000 for a new one, its capabilities are limited for the price. The one attribute which might make it worth part of that premium is its portability. Meade has its imitator, the $600 ETX. Optically they're said to be comparable, but I wouldn't want one. I've lost patience with junky telescopes, and the cheap plastic construction of the ETX makes it just that. I'd much rather have a used Pronto, or even a Ranger, if the Q was too expensive.
I love my 155mm Astro-Physics EDT! But it's not the most
portable thing in the world. It takes about twenty minutes to set it up
or take
it down.
About
ten years ago I saw the then-new Starsplitter Compact
two-pole truss Dob design and thought it might be just what I was
looking for: a highly compact, quick to set up scope, ideal for car
travel and camping, yet big enough that I need not feel deprived by
the absence of the big refractor. I ordered a 10" f/6. It has turned
out to be a good choice, though it's not the simple delight my other
scopes are. Once everything is working right, the views are really
excellent. The Nova mirror was originally a bit astigmatic and had to
be sent
back. Steve Dodds at Nova did an excellent job of fixing it. Now it's
probably the best mirror I've ever owned. With a small 1.8" diagonal
mirror, the deep-sky views easily surpass those of the 155 EDT, while
planetary views are comparable, or even superior when conditions are
excellent.
Alas, getting everything to that sublime state of perfection isn't
as easy as I'd like. For one thing, the mirror, a thick slab of
glass, takes hours to cool down, exacerbated by the unventilated
design of the mirror box. Then there's that persistent bane of all
reflector owners...collimation. While not hard to do with the right
tools, this scope isn't quite stable enough to hold alignment
perfectly as it moves around the sky.
The curved diagonal holder is prone to vibration, though if you move the scope gently it isn't an issue. The shroud is well-made, but not well-fitted. It's too baggy, quick to sag into the optical path, or be blown into it by the slightest breeze. The eyepiece unavoidably sticks straight out from the side of the scope, which is uncomfortable when viewing objects at low altitudes. Finally, the scope is too short for me at my awesome height of 6'2". I have to bend down to look through it even when it's at the zenith, and when pointed low I have to practically sit on the ground. I usually stand it on a couple of cinder blocks, which helps a lot.
This is not to say that the telescope is lacking in good
qualities! The JMI 2" Crayford focuser is nice. The Astro Systems
diagonal
holder works well. Overall construction quality is high. The original
mirror cell was very poor, but since then Starsplitter has upgraded
them to a metal design, and Jim Brunkella was kind enough to give me
one. The scope moves very smoothly. Its portability cannot be
faulted. It's impressive to be able to pick up and carry an entire
10" telescope. It only weighs about 50 pounds and sets up in just a
few minutes. I have installed a dew heater behind the diagonal mirror,
which keeps me going on the dewy nights the scope often encounters when
it's not visiting the Mojave or Sonoran deserts.
All in all I'd call the scope a worthwhile compromise. It's easy
to get it where I'm going. Once it's cooled down and collimated,
it gives some of the finest views I've ever had.
The PST is truly the most
sublime $500 an
astronomer can spend (well,
as long as he already has a good nighttime telescope). Right
out of the box it shows bright, detailed views of solar prominences as
well as surprisingly fine views of filaments, plages, and other surface
features. With the added 40mm etalon it delivers views of even higher
contrast, with very dark filaments, luminous active regions, and swirly
"spiculation" that looks like iron filings arranged by a magnet. It
could hardly be more compact, and its design is elegant and easy to
use, especially its ingenious built-in solar finder. What a totally
cool thing. Note that even Sun Boy of the Legion of Super-Heroes
approves of this instrument.
Having admired the
views available though binoviewered scopes for several years, in the
spring of 2005 I finally spent the big bucks
needed to get into this type of observing. After considering the Baader
viewer sold by Astro-Physics, I settled on the Denkmeier II with its
three-position Power X Switch because of the flexibility, convenience,
and lesser cost of the system.
My chief
selection criterion was to preserve the planetary performance of my
various telescopes, which immediately led me to the more expensive
Denk II rather than the Standard with its less precise prisms.
I have seen nothing to indicate I made a mistake. With
my 6" refractor, binoed lunar views are hypnotically sublime. Cruising
in comfort over the lunar surface at 250X or so, I notice subtle
features that escaped me before. Domes, fine rilles, crater chains,
wrinkle ridges, and even color variations call for attention from my
fascinated eyes. Slewing reveals one strange alien landscape
after another, all appearing more real and psychologically convincing
than ever before. Lunar maria are covered with wispy streaks and
patterns.
Jupiter
hangs in space as an intricately-inscribed
little ball surrounded by the tiny pearls of moons. Mars can be studied
in comfort while waiting for the brief moments that reveal the most
detail on its small disk.
Double
stars are exquisite with the binoviewer, their perfect images razor
sharp, looking almost startlingly real as they float in the field of
view.
With the
6", binoed deep sky views are impressive, but are fainter than a
single-eyed view, leading me to prefer the one-eyed view with this
smallish scope. Star clusters suffer in particular,
as the individual stars are clearly dimmer in the binoviewer. With a
scope having more light to spare I would probably feel otherwise. Using
the binoviewer under truly dark skies makes the dimming considerably
less obvious.
Using the
scope with the heavy viewer in place is somewhat awkward. It will
rotate the diagonal in the focuser if the viewer isn't sticking
straight up, unless the compression ring holding the 2" diagonal is
firmly locked down. These issues arise mainly when switching from
target to target, so a prolonged period of moon or planet watching is
less affected. The tall viewer and eyepieces often block the view
through my Telrad.
The Power X
Switch is very convenient and has a lot to do with making this viewer
as practical as it is.
As for
eyepieces, I currently have two pairs: a set of 12mm Radians, which are
on the short side for the 6" but about right for my Stowaway refractor,
and 25mm TeleVue Plossls, which provide a more useful set of
magnifications for the 6" with its 1400mm focal length. Both pairs are
satisfactory, though much of the eye relief of the Plossls is wasted by
the way the eye lenses are recessed in the barrel and the eyecups. This
is an issue for me and my glasses. The nicest binoviewer eyepieces I've
tried are the 21mm Denkmeiers. I hope to buy a pair someday.
This is one of the best astronomical purchases I ever made. My eyes lit up as soon as I saw the G11 in Celestron's first ads about it. I instantly felt this was for me, an ideal replacement for my solid but unsophisticated Astro-Physics 706 mount. I got an excellent deal from the sadly departed Pocono Mountain Optics on one of the first production G11s. The current mounts are almost unchanged except for details of the tripod and bearings. My mount arrived with a few defective parts, but Losmandy was quick about sending replacements, and has provided good service ever since.
The G11 has an impressive feeling of solidity. One knuckle rap on
its smoothly-machined black anodized aluminum conveys an instant
impression of bulletproof strength. Every detail throughout the mount
is executed with elegance and precision. The drives are accurate and
responsive. With its original RA worm, mine had a periodic error of
around 25 arc seconds, which
isn't all that great. I understand the later ones are more likely
to run in the 7 second range. I have since replaced my worm with a
newer "precision" worm, but haven't yet measured the periodic error.
Some people complain about the mount's lack of
manual slow motion controls, but I have never found it to be a
problem. Some even claim that the mount would be useless without
power, but I think that's nonsense. I can push it around by hand well
enough for visual use if need be. Note that mine is a manual mount,
lacking either digital circles or the Gemini goto system. The tripod is
very simple yet
immensely strong. The polar alignment scope works well.
I did eventually find it necessary to clean out the original grease
and replace it with a synthetic, a fairly easy task that makes a big
difference.
The mount's main Achilles heel was the exposed position of the motors and their wiring, which were protected only by vinyl covers. It was possible to wipe out the RA motor by turning the telescope too far in one direction or by letting the unbalanced head flop over. I installed optional metal motor covers which eliminate that flaw.
I use my G11 with a 6" f/9 refractor, which is pushing the limits
of the mount. Still, it's perfectly satisfactory for visual use, and
I've also done some photography which was limited more by my poor
guiding skills than by the mount. I would be surprised if it
could adequately hold a C-14 tube. I guess that's no longer an issue
since Celestron has stopped using the Losmandy mounts and has
introduced its own product which is similar in design and concept
to the G11.
Recently I upgraded some of the bearings in the G11 to the current
standard, a process which uncovered some weaknesses in the design. I
had to remove the worms, a simple enough process, but upon reassembly
the drives had a lot of backlash. Adjusting the worms against the
gears is a trial-and-error process involving making random changes and
then testing the results by looking through the telescope. Luckily this
is an adjustment that does not
need to be made often.
I normally prefer German equatorial mounts, but sometimes it's not
practical to bring one along on a trip. Sometimes I'm just too lazy to
set one up for a quick look. On those occasions I would normally use my
TeleVue Telepod head, but I decided I wanted something a little bigger
and smoother to handle my AP Stowaway refractor. On Cloudy Nights I
learned of the DSV-1 altazimuth mount being made by Raul Medina in
Phoenix, available at a good introductory price of $160. I ordered one;
it took a few months to arrive.
The mount turned out to be nicely made and very solid. Its design is
essentially that of a German head with the polar axis sticking straight
up and no counterweight. With its standard dovetail clamp, I can now
freely use my scope on either the DSV-1 or on my Skyview Pro
equatorial without swapping out the dovetail bar, as I had to do when
using the Televue head. In use, the mount is pretty stable with this
seven pound scope. Any jiggles can be attributed to my tripod, which is
on the light side for this combination. I'm able to use it successfully
for planetary viewing at powers up to 200X. One convenient feature of
an altaz vs. a German mount is that the eyepiece and finder orientation
remain the same at all times.
With the scope hanging off the side of the mount and no
counterweights, the mount is quite sensitive to being level. If off
even a little, the mount will rotate in azimuth. This is the only mount
I have which is sensitive to being level. I've also tried the mount
with a binoviewer in place on my scope, but this doesn't work very
well. I can't push the scope forward far enough to balance it properly,
and because of the weight of the bino sticking up at a right angle, any
altitude balance is lost as you raise or lower the scope.
The tension of the mount can be adjusted over a fairly wide range
using large hand knobs. The mount also comes with a pair of Allen
wrenches, though I'm not sure why. As far as I can tell, the Allen
screws only hold the mount together rather than adjusting anything.
Other altazimuth mounts of similar design exist. I haven't tried any
of them. The DSV-1 seems perfectly fine to me, and is much
cheaper than those competing mounts (or at least it was when I bought
mine). Many users of small refractors would need nothing else for quick
looks and convenient low-power scanning.
Raul also sells dovetail plates, plus accessories for mounting
specialized scopes such as the PST.
Even though it's big, clunky, and made out of polystyrene, I like the venerable Telrad better than the other available 1-power LED sighters. It's easier to align than most of its competitors, and is among the easiest to look through. Its size makes it most appropriate for scopes of 6 inches and bigger. I use one on my 155mm EDT (sorry, Roland).
I use these on my 10" Starsplitter Compact and my 92mm Stowaway because they both need something small and light. The compact base is convenient and solid. Collimation adjustments are predictable. I consider the Quikfinder a very good alternative to the Telrad, and the best choice for very small telescopes, or those with balance issues. It does exhibit more parallax than the Telrad because of its smaller size.
My first Pronto carried one of these, and it did the job perfectly well. It stayed on the scope at all times, and the alignment never budged. Some people complain that the small tinted window makes it too hard to see faint stars, but you're not supposed to use it that way. You look through it with both eyes open and see the dot superimposed against the sky. The tiny exposed circuit board which holds the dimmer control is kinda goofy, but I had no real problem with it. To me the biggest annoyance was the huge green billboard-like logo on the side, right above where it says "Daisy"...
One of these high-end toys came with my second Pronto. Though
certainly the classiest of all red-dot sighters, and the only one
made of metal, I might not pay $200 for a new one. I did enjoy owning
and using one, and miss it.
Astro-Physics Maxbright 2" Diagonal
Oh-la-la! You wouldn't think that something doing so unglamorous a
job as reflecting light through a ninety-degree angle could be sexy,
but this thing is. It is beautifully designed, carefully thought out,
immensely solid, and with its advanced high-efficiency dielectric
coating should last for decades. The TeleVue unit is nice too, but this
is
the one to get. It might be the only chance for a lot of people to own
any Astro-Physics optical equipment at all!
I consider the Radians to be the overall best line of eyepieces I've
seen. The balance of field size, eye relief, sharpness, and contrast
is excellent. With the consistent 20mm eye relief across the line,
the shorter Radians offer phenomenal comfort for planetary
observation. I own the 12mm, 8mm, and 5mm, and they are
cornerstones of my eyepiece set. They perform well at objective focal
ratios as fast as f/4.
TeleVue Type
6 Nagler Eyepieces
I have two of these, the 7mm and the 3.5mm, and they are vying with
the Radians for my affection. They're small and compact, and their
immense field of view is gorgeous. They don't produce the "kidney
bean" or blackout problems that keep me away from the other Nagler
designs. The 12mm eye relief is not overly generous, but is
usable even with my glasses on (which are thin).
I bought one of these highly regarded 50mm finders because it
offered the features I wanted: good optics, a right-angle correct image
Amici prism, interchangeable eyepieces, good focusing mechanism, and a
rotating eyepiece position. Since Stellarvue's many fans encourage
treating the F50 more like a small telescope than a mere finder, I
decided to test it as such. This involved using it with a variety of
eyepieces. I don't expect to be using the included 23mm eyepiece very
much. Not that it's a bad eyepiece, but at 8.7X in the 200mm focal
length scope, it gives an exit pupil of 5.75mm, which is more than my
eyes can accomodate. Consequently, when viewing through this eyepiece,
stars look noticably dimmer than they should, since some of their light
is falling on my iris, not passing through my pupil. I also removed the
reticle from this eyepiece, for a number of reasons. For one, it's not
necessary. I can already tell when something is in the center of the
circular
field. Secondly, as the instructions state, you can barely see it in
the dark anyway, unless it's illuminated, and mine isn't. Third, since
it's useless, there's no sense in letting the plastic disk gobble up
any light.
My tests mostly involved a
3.5mm Nagler for 57X, and a 12mm Radian
for 16.7X. The Radian gives a true field of 3.6 degrees and a 3mm exit
pupil. This results (for me) in brighter stars, a darker background,
and deeper penetration than the stock eyepiece. The field is smaller
than the original 6 degrees, but is still big enough for a finder,
especially when used in conjunction with a Telrad. If I felt like
spending $200 or more on an eyepiece for a $120 finder, my first
choices would be the 14mm or 18mm Radian.
I examined Sirius at 57X. Yes, I saw some violet color error at this
power, hardly a surprise for an f/4 objective. I could also see a faint
spike radiating from both sides of the star, an artifact of the Amici
prism. This was quite subdued and not obtrusive, much better controlled
than I've seen from some other Amici diagonals. I might not notice it
at all on a star which was much fainter. I performed a quick star test
using Polaris. The Fresnel pattern was neat, round, and well-defined on
one side of focus. On the other side I could see a vague dark line
crossing the pattern, again an artifact of the angle of the Amici
prism. This star test was much better than any I ever got from the 60mm
"Baby Brandon" refractor which I also use as a finder, and which has
some serious optical issues.
I looked at Saturn, which revealed a tiny ringed image. When focused
for the best sharpness, a small disk of spurious light expanded out of
the planet, compromising the view. I suspect this too is due to the
presence of the Amici prism, which are really not well suited to high
power astronomical use. Luckily, I don't intend to do much planetary
observing with the F50! Titan was dimly visible. Finally, I could
barely split Gamma Leonis, or Algieba, at this power.
Dropping down to 16.7X, I viewed a number of deep sky targets to
assess the F50's usefulness as an actual finder. I was quite pleased by
what it could reveal. Sky conditions were only fair that night. My site
is somewhat dark, but the sky had large areas of thin gauzy clouds
which muted the stars if they snuck up on me. Nevertheless, the F50
showed crisp fields full of sharp stars. I had a surprisingly extensive
view of M42 which included the full loop of the curving outer arms. M1,
the Crab Nebula, was easily visible as a little smudge. The Double
Cluster was a pleasingly sparkly assemblage of stars, as was M35. Most
surprisingly, I could even see NGC 2158 as a tiny blur just to the side
of the big cluster. Naturally I also had nice views of big clusters
like the Pleaides and Beehive.
As I sat there looking through this tiny telescope, contemplating
all it was capable of showing, it occured to me that people who claim
you can't really see anything through relatively gigantic 3" or 4"
telescopes may be a tiny bit spoiled and jaded.
Mechanically, the F50 is pretty nice, with a couple of caveats. One
is the main lens cap: it's lame. Very loose, it easily falls off. The
helical focuser is nice to have, but overly stiff. At 32 degrees
Fahrenheit, it became so hard to turn that I had to hold on with both
hands, lest I unscrew the whole assembly from the diagonal.
Since this test I bought a used 15mm Orion Expanse widefield
eyepiece, looking for an economical way to get a higher power from this
finder. It turned out to be a poor choice, showing highly astigmatic
stars in the outer parts of the field.
Even in my long-focus Questar telescope this eyepiece shows
astigmatism. It's a good example of what you get when you try to go
cheap on a wide-field eyepiece: not much. While usable in the finder,
the view is quite ugly, and does not properly
represent the views which are possible through this little scope. I
find it unfortunate that these finders are made with objectives of f/4
or even faster. It keeps them short and light, but it means they need
eyepieces twice as expensive as the finders themselves to perform at
their best. I vote for f/6.
Overall, the F50 is the most sophisticated, best working 50mm finder
I've seen.
VERNONscope "Brandon" 94mm
Refractor
I owned one of these from 1989 to 1991. It was a handsome thing,
with its baby blue tube, wooden tripod, and classic Unitron equatorial
mount, but ultimately the only thing I really liked about it was the
Christen triplet objective. In other respects I found that it wasn't
well designed for actual use. Permit me to enumerate its deficiencies:
The scope came with an impressive grey graphite case which
nevertheless was too short to hold the fully assembled tube. To store
the scope you had to unscrew the dewcap, remove the drawtube, and stick
them
in separate compartments in the case.
The 2" Unitron focuser looked better than it worked. The clamps were
not very positive and weren't strong enough to lock down the focuser
for any kind of photography. The drawtube was not blackened internally,
but chromed, making the telescope useless when used straight through,
since the shiny tube bounced all manner of stray light around.
The finder was the worst I have seen. Stars were horrid astigmatic
messes, so poor that the finder was nearly useless.
The mount charmed me as someone who still has a Unitron catalog
from the 70s, and it supported the scope adequately, but I still found
it poorly designed. The multiple clamps and slow motion controls were a
confusing forest of stalks to navigate by feel. The declination control
was far too coarse to be of any use for photography. The clock drive
had to take up a lot of slack before it actually began to move the
scope. The mount head came in a cool wooden case though.
This scope would have made a great ornament, and it could certainly
be used for successful viewing, but too many deficient details and
instances of poor ergonomics led me to sell the instrument with only
mild regret. The nice lens was similar in design to the original
Christen triplet, and showed some color, but was good enough for all
but the pickiest user.
Short-focus achromatic refractors have been a bit of a fad for the
past few years, largely due to the popularity of the cheap imports from
China. Since I am wise beyond other men, I have been
using small short refractors for the past 30 years. They all came from
those curious, modest, pumpkin-patch sincere A. Jaegers catalogs,
through which newer amateur astronomers have not been privileged to
pore. Jaegers refractors could not be purchased complete, but only as
parts to be assembled. My first was a 1972 3.25" f/15, my
first serious telescope. The telescope, complete with an Edmund
equatorial mount and two Brandon eyepieces, cost $180 (I would have
gotten a 4" if I hadn't splurged $36 for the pair of Brandons).
In 1974 I built a 3" f/6.5 for targets like the Pleiades nebulosity,
the Veil, and the North America Nebula, objects which amateurs were
just then realizing could actually be seen. It was a fine little scope
which I would probably still have save for a shameful mishap. I managed
to fracture the objective while trying to remove the cell from the tube
(I will say no more). I eventually sold the poor thing as a finder on a
larger scope.
In 1981 I decided to try a longer version of this sort of scope, an
f/8.6, hoping for better performance. It was a decent enough scope but
didn't really suit my purposes, being physically too long to ride
comfortably on the cheap camera tripod I was using as a mount. So in
1983 I sold that lens and adapted the tube assembly to hold another 3"
f/6.5. I still have this scope, my only relic of the days when all my
scopes were assembled by me (since then I've realized that other people
are equipped to do a better job than I am).
The lens is okay, but not as good as the original, showing a
bit of astigmatism at high powers. I have steadily refined the
tube assembly over the years. I recently flocked it and added tube
rings and a dovetail bar. At this point its biggest weakness is the
clunky 2" focuser, which is similar to the old red-knobbed Jaegers
focusers, but came instead from a strange long-defunct company in the
Philadelphia area. I have improved it by adding Teflon tape to take out
some of the slop.
In comparing the scope to a TeleVue Pronto, the Jaegers shows a
noticeably brighter image, color correction which is only barely worse,
and similar levels of planetary detail. This venerable scope's shining
moment came when I used it to stare at the phenomenal beauty of the
solar corona during the 1991 eclipse in La Paz, Mexico. It has also
played a role at various partial and annular eclipses, and served as a
finder on my old 14.5" Dobsonian.
It's too bad today's
observers don't have the option of assembling refractors from Jaegers.
Words copyright by Joe Bergeron.
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