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Uncle Rod and the Rescue Telescope

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Again in her pure component…

Sounds just like the title of the subsequent Disney Channel animated collection,
don’t it, muchachos? I wager you thought Unk could be writing in regards to the comet
nine-day-wonder, Comet 2022/E2 ZTF, dincha? That can come. To date it’s been
too cloudy or too chilly and the comet has been rising approach too late (early, that
is) on your lazy Uncle. Right this moment, the topic is Uncle Rod’s newest rescue telescope.

What in pea turkey is a rescue telescope?! A “rescue
telescope” is most frequently a contemporary iteration of the Division Retailer Telescope that
has fallen on laborious instances, has fallen about so far as a telescope can
fall. Possibly it started as a Christmas or birthday current to a youngster or an
impulse purchase by an grownup. It was shortly discovered to be poor in that its photographs
didn’t rival these of the Hubble Area Telescope. It was beneath the celebs a number of
instances and introduced its proprietor a fairly Moon however was quickly discovered to be Too A lot Hassle.
The briefly beloved scope, its splendidly gaudy field lengthy discarded, finds its
approach right into a closet the place it sits bereft of starlight for a protracted, weary time.  

The scope’s descent doesn’t cease there. Ultimately, it
turns into an annoyance, taking over room in that closet, crashing to the ground each
time the proprietor retrieves their galoshes, and making a normal nuisance of
itself. Typically it’s given away and the story up to now repeats itself. Most
usually, it’s placed on the curb, to be both plucked by the trash pickers or despatched
to its last demise. Typically it will get fortunate, although; the proprietor donates
it to a charity thrift retailer and typically, simply typically, somebody comes alongside
and offers the poor factor a second likelihood.

Anyhoo, one latest Thursday night, Unk discovered himself
arriving just a little early for a radio membership assembly held at a Goodwill Group
Middle adjoining to a Goodwill Thrift Retailer. The earlier week I’d discovered a Simpson
260
multimeter in there for the grand sum of 9 {dollars}. With just a little
time on my palms, I needed to see if I’d get fortunate once more and headed for the
again of the shop the place the electronics are saved…however didn’t get that far.

At first Unk thought he was going loopy(er). I gave the impression to be
listening to a plaintive little voice. A bit of feminine voice: “HELP ME,
UNCLE ROD! YOU’RE MY ONLY HOPE!
  My
puzzlement turned to understanding once I noticed a 4.5-inch Newtonian sitting beside
the aisle on her spindly tripod.

“Good day, baby. How lengthy have you ever been right here?”

Oh, Unk, I’ve been right here the longest outdated time!”

“Nicely, let’s take a look at you.” What was earlier than me was a present
Division Retailer Telescope (DST). You thought they have been gone? No, they, the telescopes
in-between toys and genuinely severe however cheap scopes just like the Orion
Starblast, are nonetheless with us.  They’re
nonetheless bought in precise malls, but additionally in passion outlets and, in fact,
on-line. Most of them are the ever-present 114mm (4.5 inch) Newtonians, 60mm refractors
being much less quite a few than they as soon as have been.

How is the present crop in comparison with these of yore, just like the
well-known Tasco 11-TE? In comparison with 60s – 70s DSTs,
they’re largely worse. The large and debilitating drawback is their mounts are
shakier (they usually weren’t the Rock of Gibraltar approach again when), picket tripods
having given approach to extruded aluminum jobs barely ample for low energy. Eyepieces,
nonetheless, are undoubtedly significantly better now. Most are pretty good 1.25-inch
oculars that blow the doorways off the .965-inch horrors of the previous. Finders have
improved, too, purple dot jobs having displaced small-aperture, stopped-down optical
finders or the dreadful “reflex” finders Jason-branded scopes as soon as sported.

That wonderful field promising wonders…

“However how in regards to the optics?” 
They’re typically well-made, BUT… Again within the wonderful
day, 114mm reflectors from Japan, and, afterward, 114mm reflectors from China,
had spherical main mirrors, yeah. However in addition they had focal ratios of f/8.
At f/8, a 4-inch spherical mirror is sort of near ¼-wave of wavefront error
and might carry out very properly. Alas, most DSTs now possess f/5 – f/6 spherical
mirrors. At that focal ratio they strategy a half-wave of error. Not horrid,
maybe, however worse. Why the transfer away from f/8? I suppose f/5 tubes could also be
cheaper to supply and trigger much less stress for at the moment’s pitiful DST mounts.

Wanting on the waif earlier than me, I famous the label on her
(plastic) focuser learn, “Celestron 114-AZ SR D=114, F=600, F=5.2, MADE IN
CHINA
.” I nearly walked on, realizing the limitation that will impose given
the spherical mirror I knew this little lady would have. However I didn’t. I’ve
seen Celestron 130mm scopes with spherical mirrors do OK on the Moon and different
topics at related focal lengths, so why not?

I’ve additionally gotta admit the Celestron tugged at my coronary heart
strings, trying unhappy and pitiful together with her banged-up metal tube tarted-up with
paint to make it seem like carbon fiber. 
And I’m all the time looking out for scopes to cross on to enthusiastic younger
undergraduate astronomy college students. Additionally, there was the worth tag on her, “$19.99.”
Lastly, paraphrasing Charlie Brown, I mentioned out loud, “Moreover, I believe this
little telescope wants me
.”

The Celestron, who informed me her title was “Tanya,” begged to
be taken dwelling: “Uncle Rod, my purple dot finder alone is price 20 bucks. PLEASE
GET ME OUTA THIS PLACE!
” I took a have a look at her main, which appeared
shiny and clear, and surveyed the remainder of her. She appeared full with a
couple of low-cost Plössls, one in her focuser and one in her little eyepiece tray.
Nicely, nearly full; her aperture cowl was lengthy gone. I scooped the lady up
and headed to the checkout, “Oh, thanks, Rod! I do know we’ll be nice
pals!”

A tough-knock life.

Again dwelling after the radio membership assembly, Miss Dorothy wasn’t
too stunned to see me are available in with yet one more wayward scope in my arms. She was
quite stunned by the 20-buck value, although. 
You recognize, so was I. Sitting within the kitchen, Tanya appeared far
higher than she had beneath the cruel fluorescents on the Goodwill retailer. Subsequent
step was seeing exactly what was up with the lady.

My preliminary examination confirmed one of many two eyepiece
locking screws was jammed. It was so tight I needed to resort to (rigorously) unscrewing
it with a pair of vice-grips. To my shock, it wasn’t cross-threaded and
stripped, simply screwed down terrible tight. When it was free, I used to be capable of extract
the 9.7mm Plössl (each eyepieces being Celestron’s extra-cheap ones with metallic barrels
however plastic our bodies) and look at the secondary mirror. A glance within the now empty
focuser confirmed a number of large blemishes on it. Would possibly simply be filth or is perhaps
harm to the coating—there isn’t any telling what a child who acquired a telescope
as an alternative of the battery-powered scooter they actually needed will do to torture the
poor factor.

In any other case, it was clear Tanya had certainly led that proverbial
hard-knock life. There have been a number of small dents and dings on the tube, and
one thing—who is aware of what?—had been sprayed on it right here and there. There was additionally
loads of the dreaded Chinese language glue-grease (apparently fabricated from ground-up weasels),
which had migrated from focuser, to tube, to mount, to tripod with the help of
younger fingers.

There was a crescent Moon within the sky, so naturally I acquired little
Tanya into the yard for a glance. Earlier than doing that, I gave each her oculars
cleansing—they have been filthy. How was that Moon? Not dangerous. It was sharp
sufficient given the apparent mis-collimation of the un-cooled-down optics, poor
seeing, and the one honest high quality of the eyepiece (these plastic-bodied Plössls
are used on a lot of Celestron’s/SkyWatcher’s lower-priced scopes). Anyhow,
Tanya did properly sufficient I declared she had potentialities and informed her we’d get
her cleaned up within the morning.

That morning, if not too early that morning, I set
off to acquire one thing I knew I’d want, paper-reinforcers to make a middle dot
for her main mirror so I might collimate her. To my astonishment, Publix had
none. Neither did Walgreens. Nor did the Walmart meals retailer. I lastly turned
some up at CVS medicine. Is there a paper-ass*&^% scarcity or one thing?

Again dwelling, out within the Batcave, my radio shack cum-workshop
of the telescopes, I assumed my first job would to be to scrub the secondary.
As you possibly can see within the picture beneath, the secondary’s spider is an integral a part of the
plastic fore-end of the tube, as is the finder mount.  I noticed a number of Philips-head screws and
eliminated these. It was obvious the focuser would additionally need to be eliminated to get
the plastic part free.

I did that, which was simply as a lot of a ache as eradicating the
different screws, since all have been held in place by tiny nuts and Unk couldn’t get
his fingers very far into the tube as a result of thick plastic spider vanes. Lastly,
all screws have been eliminated, however the plastic meeting nonetheless refused to budge. It
was fairly clearly glued in addition to screwed into place. One of many issues
with this and related little scopes is they don’t seem to be made to be maintained—they’re
like Chinese language puzzle bins.

Prepared for collimation.

Quite than attempt to defeat the glue, I made a decision I’d clear the secondary
in situ. With the focuser eliminated, the opening within the tube was giant sufficient
to permit that. To my shock, light cleansing took care of the a number of spots
of filth or no matter (it nearly appeared as if—horrors—somebody had spat on the secondary!).
It was now clear and fairly, and I used to be in a position (with some problem) to get the
focuser again in place.

Subsequent up was collimation, however to do this, I’d need to center-dot
the mirror. I used to be stunned to not see a dot on the first. Even Celestron’s
lower-priced “beginner astronomy class” scopes just like the aforementioned Starblast
have ‘em. I suppose they don’t trouble with these just like the 114AZ certain for
passion/toy/malls.

How do you middle dot a mirror that ain’t acquired one? Seize a
compass, draw a circle the identical diameter as the first on a chunk o’ paper,
fold it into quarters, snip off the apex of the cone shaped, unfold it, place
it on the mirror, and thoroughly make a dot on the first by way of the opening. Middle
the paper reinforcer on the dot. Should you’re as OCD as Unk, you’ll then take a Q-tip
moistened with alcohol and gently take away the sharpie mark.

I collimated the little factor utilizing the Celestron combo
sight-tube/Cheshire I’ve had for years. If you wish to know how one can do Newtonian
collimation, see my weblog entry on the topic.
Having achieved a Newtonian pretty just lately, I didn’t need to reference my very own
article. Denouement? Secondary and first have been each off a substantial
quantity however have been simple sufficient to get “in” in just some minutes.

Achieved for the second with the OTA, it was time to see what I
might do to enhance the mount. The azimuth axis had a wholesome dollop of that glue-grease.
A lot of the viscous stuff the tube tended to proceed shifting in azimuth when
I finished pushing it. A bit of of my favourite remedy, DeOxit, and the appliance
of some Blaster artificial lube freed up the movement fairly a bit. There was solely
a lot I might do, for the reason that azimuth axis was pressed into place and would
have been tough or inconceivable to take away, however it was higher.

Wasn’t a complete lot to be achieved for the altitude axis. A
little lube within the trunnions and that was it. The altitude slow-motion arm
(speak about a blast from the distant previous) didn’t want any consideration.  Lastly, I used some 99% isopropyl alcohol,
DeOxit, and WD-40 to banish the numerous patches of weasel grease on mount and
tripod.

The spider is d a part of the tip meeting of the tube. 

I then returned tube to mount and proceeded to see if I might
do sumpin in regards to the stiff, wobbly plastic focuser. Changing its glue-grease with
artificial lube helped. I used to be additionally capable of make its movement simpler by adjusting
the 2 screws on the rack and pinion focuser’s underside. Nonetheless, it was clear
the main target tube would all the time be floppy. Like the same plastic focuser
SkyWatcher makes use of on its “tabletop” Dobsonians, there isn’t any lock screw, and mechanical
tolerances are giant. I assumed if the scope carried out midway decently, I’d
take into consideration some Teflon shims or one thing.

Last item? I attempted to make poor Tanya fairly once more
and was partially profitable. I used to be, with mucho scrubbing and utility of Pledge
furnishings polish, capable of take away many of the nasty-looking spots on the OTA.
Oh, she’ll by no means seem like she did the day excited palms pulled her out of her
Technicolor field, however, yeah, she appeared a lot higher. I picked her up,
cradled her in my arms, and took her to the yard to acclimatize forward of
darkness. You recognize what? The little scope positively glowed sitting there.

Whereas ready, I assumed I’d study just a little one thing about Missy.
It seems she is a at present bought scope retailing for about 100 bucks at—fittingly—Kohl’s
division retailer. Appears to me I’ll even have seen a 114AZ within the Kohl’s up the
road final Christmas.  I additionally solved a thriller:  what the “SR” within the telescope’s mannequin quantity
means. The 114AZ SR is smartphone prepared. What does that imply? As
she got here from the manufacturing facility, the scope was furnished with just a little cellular phone
mount so you might take footage by way of the eyepiece. That mount, which apparently
concerned rubber bands, was not with Tanya at Goodwill, and had little question gone
lacking together with the aperture cowl (and a pack-in DVD of the Starry Evening software program)
way back.

I sat and waited for it to get darkish sufficient. However you recognize
Unk; I acquired “go” fever: “Hail, it’s darkish sufficient to have a look at the Moon.” And it
was. The distinction between bedraggled Tanya the earlier evening, and tonight’s
prom-queen Tanya was greater than palpable. The simply earlier than first quarter Moon was
merely delicious.

At 60x together with her so-so (or possibly not so so-so) 10mm
eyepiece, Selene was a factor of marvel. With darkness having arrived, I assumed
I’d push her a small quantity. I plucked certainly one of Celestron’s barely higher Plössls,
a 6mm, out of its case to see what she might do with 100x, a extra sensible magnification
for observing the Photo voltaic System. With just a little extra energy, the trio of craters,
Theophillus, Cyrillus, and Catharina, was merely breathtaking.

Was the wee scope good? Hardly. Even at “simply” 100x,
there started to be issues. Not with the optics, however with the mount. At that
modest magnification, it started to frame on unusable. Oh, I might get the
telescope in focus, however it was fairly shaky and I needed to train a lightweight contact.
Mix that shakiness with the shallow depth of focus of its quick focal ratio,
and a scope like this challenges the very individuals it’s supposedly designed to
serve, youngsters and freshmen. Nonetheless, it’s undoubtedly at the very least OK with the
two equipped eyepieces, which furnish 23x and 60x.

Feeling and looking significantly better!

Possibly the largest shock of the evening was ol’ Jupe. He’s
not a straightforward object for small telescopes, actually, and is the place many low-cost ones
fall fully aside. “Is that Jupiter or a custard pie?”  With the 6mm in place we headed for the King.
I didn’t count on a lot and was frankly amazed. The 4 Galileans have been sharp,
certain, however the large deal was I used to be seeing banding, loads of it, on the disk, and
possibly the even Nice Purple Spot, too (I wasn’t certain whether or not it was seen or
not; I checked later and it was).

Whereas the sky was starting to haze over, because it had been
since sunset, I simply had to try M42. The Trapezium was simple and
there was as a lot nebulosity on view as I’d count on any 4-inch to indicate on a
less-than-average evening. Oh, we made a number of different stops as properly. The ET Cluster,
NGC 457 was fairly if extra subdued than on night. However we ended on Luna
once more. I couldn’t cease marveling what at what this previously debased little
telescope was exhibiting me.

Frankly, I used to be thrilled I’d been capable of carry this unhappy little
refugee again to life. Sadly, whereas the sky wasn’t trying any worse
than it had, and the winter stars have been glittering bravely within the haze, the one
factor that all the time signifies it’s time for Unk to finish an observing run occurred.
My ft acquired chilly. When that occurs, it’s finish of story, sport over, zip
up your fly. I picked the little scope up, deposited her within the Batcave (her
aperture lined with a bathe cap), and was inside watching tv with
the cats in just some minutes.

When the time is correct, sure, Tanya will undoubtedly go to
some deserving younger individual, however until then, yeah, it’s simply as she mentioned; we’re
going to be nice pals.

 

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