# Stabilizers/dampers for refractor telescope

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I have a basic refractor telescope. It's pretty light and so it catches vibrations and they never really settle down. Can I attach some dampers on it to cushion these?

It depend where vibration are. Often (if you have a good mount for the telescope) all the structure vibrate and there are some good anti-vibration feet that can be useful. If the tripod isn't the problem and the vibration are only near the telescope, probably the problem is the mount that is under-sized for you telescope. In this case the only good way is change the mount with a sturdier one.

Depending on the root cause, vibration damping pads may or may not help. Some telescope vendors sell sets of three for $50 or so; an Internet search also yields a few do-it-yourself recipes using silicone caulk, sorbothane insoles, etc. Other home remedies are possible, such as adding weight or shims to the mount, or hanging a chain from the optical tube assembly. ## Telescopes - Instruments for Observation of the Sky Bresser offers beginners, advanced amateurs as well as specialists and researchers appropriate telescopes. Beginners find the perfect start in astronomical observations with our complete systems. These systems contain every accessory that is needed for an immediate start. Advanced observers will find the appropriate telescope in our Bresser Messier range - these telescopes stand for high quality at fair prices. Would you like to order from us as school, university or public institution? Would you like to order from us as a school, university or public institution? Please direct your enquiry to info(at)bresser.de, stating the invoice address (delivery address if applicable). Delivery is made on account. This also applies to a value of goods of more than 1000.00 Euro. #### Biological Microscopes Biological microscopes (life science microscopes) are available in monocular, binocular and trinocular versions as well as in digital version with one screen. These microscopes are used for sample analysis (incident or transmitted light) at magnifications between 20x and 1000x. Applications include biology, botany, research, gemmology, entomology, mineralogy and botany. Biological Microscopes ## Stabilizers/dampers for refractor telescope - Astronomy Subtotal ( Items) .00 Have a promo code? Enter it during checkout! The most popular accessories for your new telescope! Start here to find the perfect telescope for you! NEW: Nature DX ED Binoculars Celestron’s award-winning Nature DX binocular gets a major upgrade with the addition of ED objective lenses. NEW: Elements ThermoTank 3 On the trail, at the job site, in the classroom, or simply sitting at home relaxing – the Celestron Elements ThermoTank 3 will keep your hands toasty. NEW: Elements ThermoTorch 5 This rugged, 3-in-1 device features a true tactical 3-mode flashlight, a hand warmer, and a portable power bank for recharging your personal electronics on the go. ## Astro-Physics Starfire Refractor Astro-Physics Starfire Refractor> Ever since reading Alan Dyer’s article Astro-Physics Refractors Big & Small in the 1993 September issue of Astronomy magazine, I have dreamt of someday owning an AP-155 f/7 EDF Starfire refractor. Well, it’s taken a couple of decades but I finally acquired Astro-Physics Starfire Refractor a few months ago, courtesy of one of my oldest astro friends, Terence Dickinson. Terry, as many amateur astronomers will recall, is the author of the bestselling book Night Watch, and along with Alan Dyer, the all-time favorite The Backyard Astronomer’s Guide. Terry was willing to sell me his treasured 6.1” apochromat so that in his words “It can continue to be used under the much clearer and transparent skies you enjoy near Flagstaff, Arizona”. Naturally I did not argue with that! Fig. 1 The 155mm f/7 Starfire EDF housed in my observatory, with a piggy back mounted TMB-92 f/5.5 all on a Losmandy G-11. To quote from Alan’s 1993 review “Optical performance of the 155EDF was impressive. It produced nary a trace of false color even on Venus. Equally impressive, this scope provided superb images as soon as it was set outside. Even in sub-freezing temperatures, image quality, though not perfect at first, was surprisingly sharp from the start. In cold weather, after a modest settle-down time of 30 minutes, in-focus star images were textbook Airy disks with a well-defined first diffraction ring and a trace of a second outer ring. There was no sign of spherical aberration, lens figure changes, heat plumes, or distorted Airy disks due to tube turbulence.” As stated on the Astro-Physics website with reference to this 1990s vintage scope, the Astro-Physics Starfire Refractor was initially designed for film-based photography, including 35mm and medium format cameras. For the 6࡭ film format, it offered an oversized 4” focuser and a 2 element field flattener. This, in combination with the 155mm objective lens tripled, served as a 5 element wide-field f/7 astrograph, with a 3.2 x 3.7 degree field on medium format film. They go on to say “At the urging of our customers, we also offer the same excellent 155mm f7 lens in a lighter weight tube assembly with our 2.7″ focuser”. Fig. 2 Close-up of the imposing lunar crater Clavius, shot at f/28 under very good seeing. Some of the smallest features resolved are about a mile in diameter. This Astro-Physics Starfire Refractor model can be used photographically with a 35mm (or equivalent format) camera at prime focus or at a fast f5.3 with AP’s optional flat-field telecompressor. My telescope is equipped with the 2.7” focuser and the above reducer-corrector. It is permanently mounted in my observatory on a Losmandy G-11 and coupled piggy-back with a TMB-92 f/5.5 refractor (Fig. 1). I can alternate this rock solid combination as primary imaging instrument and/or guide scope. Remembering that AP-155 was designed over 20 years ago both for visual work and film-based astrophotography (and sadly is no longer in production), how well does it stand up today? I was especially curious to see how it would perform with my Hutech modified, full-frame Canon 6D, a ZWO ASI-120MC webcam and of course various modern eyepieces. Visual Performance I tested the Astro-Physics Starfire Refractor with several of my favorite eyepieces, both 1-1/4 and 2-inch diameter, with and without a quality 2-inch Barlow lens. These included the following: 3.8mm Orion Lanthanum 8 and 14mm Meade ultra-wide 24mm Tele Vue Panoptic 23mm Celestron Luminos 82 o 30mm Explorer Scientific 82 o . I even tried a 1980s vintage 12.5mm eyepiece. Fig. 3 Section of the lunar surface extending from Albategnius at top to the Hyginus Rima at bottom shot at f/14 under good seeing. orthoscopic eyepiece for good measure. As one might expect, the grand old Starfire lived up to full expectations. Its apochromatic triplet consisting of 2 crown and 1 ED elements was essentially color free, exhibiting incredible contrast and exquisite detail on the Moon, Mars, Jupiter and Saturn, all of which have been prominent the past several months. The only hints of extraneous color on the three planets, was atmospheric dispersion due to their low elevation in the sky. That was easily dealt with, however, by inserting a ZWO atmospheric dispersion corrector in front of the eyepiece. On one night of particularly good seeing even the Encke division on Saturn’s well extended rings was easily resolved. Perhaps most pleasing with lunar and planetary viewing was the pastel-like subdued coloration on Jupiter and Saturn. Likewise with deep sky viewing both at f/7 and f/5.3 with the focal reducer, images were tack sharp with pin point stars and superb contrast under good transparency. Under good seeing, stars exhibited well defined diffraction patterns and test objects like the Double Double in Lyra was an easy target. Imaging Performance Since my primary passion and enjoyment is still astrophotography, I was naturally anxious to put the Astro-Physics Starfire Refractor to the test. Having had Fig. 4 Mosaic of the M-8 and the NGC 6559 complex imaged at f/7 without field flattener, with a modified Canon 6D and LPS-V4 filter. Each half of the mosaic is a composite of 4 x 3 minute exposures at ISO-6400. an excellent TMB-130 f/7 for many years and recent access to a friend’s AP-150 f/8, of pre-Starfire vintage, I had an ample collection of images for comparison. Although I am certainly not an accomplished lunar and planetary imager, I recently obtained a ZWO ASI-120MC camera for that purpose. I opted for the color version of this easy to use camera to learn the basics of webcam image capture and processing, and not be encumbered with RGB filter wheels and related requirements. For lunar imaging I simply use the grayscale option and always shoot through a deep red filter to minimize the effects of atmospheric turbulence. The resultant AVI capture sequences were processed first in AutoStakkert!, sharpened in Registax-6 and finished in Photoshop CS6. In order to obtain the largest practical image size, when seeing is fair to good, I double stack two 2x Barlows, for an effective focal ratio of f/28 and focal length of approximately 4000 mm. If seeing is only fair, a single 2x Barlow is used. The results so far have been most pleasing (Figs 2 & 3). Fig. 5 M-31, 32 and 110, imaged at f/5.3 with the AP telecompressor and modified Canon 6D with LPS-V4 filter. This is a composite of 5 x 5 minute and 3 x 3 minute exposures at ISO 6400. For deep sky imaging, I use a Hutech modified, full frame Canon 6D, typically in combination with an IDAS LPS-V4 filter. This coupling is particularly well suited for emission nebulae and/or under moderately light polluted skies. Thanks to this camera’s effective noise suppression capabilities, I generally shoot between ISO 3200 and 6400, with 3-5 minute exposure times. A half dozen or more exposures of this duration are then stacked in either Registar or Photoshop. As can be seen in Fig 4, a mosaic of overlapping images of the Lagoon nebula region taken at f/7 prime focus, stars appear only slightly distorted at the edges of the frame even without a field flattener. At f/5.3 with the reducer-corrector in place, stars are tack sharp to the edge of field and the effective field of view is 1.7 x 2.4 degrees, wide enough to encompass M-31, M-32 and M-110 in the same frame (Fig 5). So, how well does this nearly 25 year old telescope design perform in the digital age? Superb optics and construction still rank it as top contender by any measure. I have observed and photographed with some of the best telescope designs in my nearly half century as an amateur astronomer, including classics and some of the best modern brands, but have yet to see a better 6-inch apochromatic refractor. Kudos to Roland Christen and Astro-Physics! Might one hope for a sequel? Klaus Brasch, Ph.D. is a retired bio-scientist and a public program volunteer at Lowell Observatory. He joined the Royal Astronomical Society of Canada in 1957 and has been an avid amateur astronomer ever since. A frequent contributor to Astronomy Technology Today, JRASC, Sky News and Sky & Telescope, he enjoys astrophotography from his observatory near Flagstaff, Arizona. And to make it easier for you to get the most extensive telescope and amateur astronomy related news, articles and reviews that are only available in the magazine pages of Astronomy Technology Today, we are offering a 1 year subscription for only$6! Or, for an even better deal, we are offering 2 years for only $9. Click here to get these deals which only will be available for a very limited time. You can also check out a free sample issue here. By the end of this article, you'll know whether the MaxUSee 70mm Refractor Telescope Review is the right scope for you. ### About The MaxUSee 70mm Refractor Telescope is a sturdy, lightweight and easy to use telescope for astronomy beginners. "Out of the box, you'll be confronted with one of the best beginner optical astronomy instruments in the telescope industry" claims MaxUSee. For it's price range, the MaxUSee Refractor Telescope is probably one of the best deals on Amazon right now. Click the link below to view the lowest price on Amazon. ### Reasons for Purchase The MaxUSee is one of the most experienced companies in manufacturing and engineering advanced optical equipment for both beginners and experts. The benefits for purchasing the MaxUSee Refractor Telescope. • Most Portable telescope in the industry. A great option for astronomy beginners. • Large 70mm aperature lense. • Magnification Range from 16X to 200X. • Twointerchangeable eyepieces. (20mm and 4mm) Furthermore, the MaxUSee Telescope's portability makes it extremely easy to be operated by newcomers and astronomy beginners. ### Price Range For individuals entering the hobby, it isn't recommended to splurge on an advanced telescope without prior knowledge. It's a better idea to purchase a lower-end telescope before purchasing more advanced equipment. The MaxUSee 70mm Refractor Telescope is a terrific piece of technology that can serve as ones first telescope. ### Comes Included With The MaxUSee 70mm Refractor Telescope comes with these additional items: (Free of Charge) • Four magnification eyepieces • Durable and Easy to Use tabletop tripod • Phone adapter included for video camera and photo capturing. ### Conclusion Overall, for$50 dollars, the MaxUSee 70mm Telescope is the best option for beginners. It's portablity makes it easy to travel with. Furthermore, an in-depth manual comes with the telescope giving you step by step instructions on how to view certain objects.

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## 6 Replies to &ldquoBeginner’s Guide to Astronomy – Refractor Telescopes&rdquo

I think you mean “acrhomatic” and “apochromatic” in this review. Achromatic telescopes are the common department store kind, using lenses made from an achromatic pair of flint glass and crown glass elements. Apochromatic telescopes employ lenses made from at least three pieces of glass with different indices of refraction.

If you didn’t know, “Chromatic” telescopes are okay for casual observing, but an “Apochromatic” scope, although more expensive, is worth the investment! Lens material is part of this equation. Lens can be made out of Fused Silica and Fused Quartz material, which come in Commerical, Optical, UV and IR grades. It goes without saying, but the better the glass and the better the coatings the more a refractor will cost…

My glasses alone produce enough chromatic aberration to render the stars almost invisible. No, thank you!

Having that third lens to reduce chromatic aberration makes a huge difference, even on smaller refracting telescopes. Obviously, as others have stated, the better the lens material the better the image/view, but even the low end ones improve over simple two lens refractors.

Actually, high-quality “ED” refractors using two objective elements made of special low-dispersion glass can give near color-free performance. While 3-lens APOs give a 󈫺” performance, they are the most costly ($400-$1,000 per inch of aperture) and are heavy. Quality ED scopes are less expensive ($200-$300 per inch of aperture) for 80-mm and 102-mm class scopes. I would rate their performance at 𔄡” to 𔄡.5” for visual use (less critical than for those who image). The lenses used in ED or APO scopes will have full multicoatings that cheaper scopes will not. High-quality refractors will also sport dual-speed Crayford focusers. Installing a FeatherTouch or Moonlight focuser will typically add $300 to the cost of a scope with a generic dual-speed focuser. Also note that high-quality refractors do not come with diagonals. A 2-inch dialetric diagonal will cost between$140 and $180. Traditional refractor tubing was steel or thick gauge aluminum. Newer designs are employing carbon fiber, which reduces weight considerably. Quality scopes do not come with eyepieces. (This is a whole other area. Poor eyepieces with a great scope will give mediocre results.) Following is a very good “entry level” ED-scope: >Stellarvue 80ED Raptor (carbon fiber tube) with dual-speed rotating focuser, collar and Vixen style mounting plate, collapsible dew shield, and case:$600
>Stellarvue 2″ dialectric diagonal: $140 if purchased with scope >Vixen PortaMount 2 (a sturdy but lightweight alt-az mount):$330

As you can see, a high-quality ED scope and mount will cost about $1,100 (about 3-4 times of a “budget refractor” that includes the mount), but the setup described above will last with care for 20-30 years and give performance the cheap scopes can never match. Indeed… eyepieces are key! A borrowed$500 TeleVue eyepiece turned my little 4″ Meade S/C into a whole new telescope!

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## Officina Stellare 152 HYPER APO Refractor

This is a mint condition OS 152 - absolutely gorgeous to look at but more importantly totally spectacular to look through. Looking at the moon through this scope feels like you are floating above a three dimensional orb. Deep sky objects at f/8 are also wonderful visually. The beautiful graphite tube was made in Italy and the amazing triplet objective in the LZOS factory near Moscow. The objective design is by Thomas Back. The lens is from OK-4 super ED glass with an outer crown of special dense glass and hand figuring to control any aberations. The OTA has internal baffles from the lens all the way to the focuser laser cut from stainless steel. The carbon fiber is lightweight but also rigid across a wide range of temperatures. The dew shield is retractable for transport and there are internal electric microfans to control any air currents if needed. The focuser is Starlight instruments 3.5 inch with Feather Touch micro adjustment. I am including Officina Stellare (red!) rings as well as dovetail bars above and below the OTA. In addition I had a Pelican 1780 T case made for the scope with custom foam inserts. The cost for all of the above was $14,450. I will sell the package for$9,500 even. Shipping to continental US only please - buyer pays shipping and PayPal fees.

Price is firm. I am the second owner. The telescope was purchased for testing our new telescope piers.

## Astronomy Technology … Yesterday: Rescuing a Storied Cooke Refractor Telescope

Douglas Bullis has lived all over the world in search of perfect skies. He finally retired in the arid Karoo highlands of South Africa, one of the three or four darkest regions in the world. After a forty-year career writing books about business, world cultures, art, and fashion designers, he discovered there’s a left side to the brain, and he’s been writing about astronomy ever since.

Who doesn’t dream of discovering that a forlorn princess pines away in a forgotten castle for a handsome hero to come to her rescue and take her away to that dream kingdom far, far away? And if the damsel is a forgotten historic 8-inch refractor doomed to the scrap heap by the pitiless hand of time and money, it becomes a fairy tale for astronomy buffs that even Disney couldn’t better.

Figure 1: Port Elizabeth, South Africa Thos. Cooke & Sons 8-inch refractor in 2016. Source: Nielen Schafer, Port Elizabeth People’s Astronomy Society.

And of course, the hero arrives riding a neighing charger (cleverly disguised as an Airbus 380), rescues the forsaken beauty, and they live happily ever after, at least between twilight and dawn. It sounds too good to come true.

But in Port Elizabeth, South Africa, it did come true.

Let’s start with the damsel (Figure 1): Her measurements wouldn’t make the beauty-pageant news. But at 102 inches tall, 16 inches wide, and 63 inches from stem to stern, she is as comely as any astronomer could wish. And who but an astronomer would delight in a shoe size of 38 inches with a two-inch cast iron sole? With shoes like that, you only need one, yet on a lass of 126 years, it looked just right. The best compliment ever paid to her was that she was built like a two-ton Swiss watch.

She really was Astronomy Technology Yesterday – 1891 to be exact. She represented the pinnacle of astronomical optics, mechanics, and instrumentation available to the (very) deep-pocketed amateur astronomer of the Belle

Epoque era between 1880 and 1914 (Figure 2).

The Cooke catalog’s title page conveys no real sense of what a true professional-level turn-of-the-century “Gentleman’s observatory” actually looked like if one were to step into the past and pay a call. Then one day in February 2015, this author and a couple of other South African amateur astronomers walked through the door of an unpromising dark-gray building and beheld a sight that could as easily been seen in February 1885 or even 1915. The huge mechanical device before us was both a bewonderment and disheartening. (See these Flickr pages: https://www.flickr.com/photos/[email protected]/albums/72157659849343183 for the full image set taken on that visit.)

But as we got over the feeling we’d walked into a time warp, it dawned on us that hidden inside the down-at-the-heels building was a double-door multi-shelved cabinet of original brass and glass equipment that had lain practically unused since the 1950s. The Pepos Observatory was so crammed with 1890s technology that we concluded nothing like it had been assembled intact in one place since the 1910s. To wit:

• 8-inch (203mm) f/15.1 (3048 mm f.l.) Fraunhofer objective.
• Cast-iron pier and German equatorial mount with gearing for lunar, solar, and sidereal rates, plus manual slewing capability.
• Working clock drive in glass-windowed metal enclosure, running time approximately eight hours.
• Low-dispersion stellar spectroscope in custom mahogany box (Figure 3).
• High-dispersion solar spectroscope in custom mahogany box.
• Filar micrometer in custom mahogany box (Figure 5).
• 5-inch diameter Ronchi grating.
• Astronomical protractor in custom mahogany box.
• Spirit level in custom mahogany box.
• One of the Troughton & Simms 1839, 42-mm portable transit telescopes dispatched by the British Royal Navy in connection with the Venus transit of 1882. (This effort was intended to establish an accurate time base of geographical locations so that, although the Sun might never set on the British Empire, the Royal Navy would be aware of where exactly in the sky that Sun might be at any given hour anywhere in the world.)
• Six original Ottway Huygens eyepieces (draw-tube diameter 30.06-mm or 1.2 inches) in a wood box (Figure 4).

The first glimpse was enough to make any astronomer’s heart soar. The second glance was enough to clip that soar’s wings. This magnificent collection was facing the worst end an astronomy devotee could imagine: Her exquisite lens in a musty museum all the rest of that gorgeous workmanship melted down as scrap.

The dwindling membership of the Port Elizabeth People’s Observatory Society was at wit’s end with a seemingly insoluble dilemma – the telescope was too valuable to sell, too big to move, and too expensive to restore.

A diligent search undertaken by the country’s professional body, the Astronomy Association of South Africa, turned up no person or organization in South Africa with the financial base, technical expertise, and desire to restore such a complex piece of equipment. Pepos was the most beautiful albatross the spirit of astronomy could devise.

Then came the really big problem: Where do you put one of these with some assurance that the place won’t be light-polluted out of existence in a decade or so?

Rehabbing a telescope of the Cooke’s antiquity and deteriorating condition is much more than a gallon of Brasso and a lot of elbow grease. Brass and iron came very cheaply in 1800s Britain, and it showed. Astounding masses of brass were foundry-cast and precision-machined in those days, yet each individual piece was unique.

A lathe operator might turn out individual screws for hours by hand, then be assigned to gears, or handles, or knurled focuser knobs. Parts matched yesterday by lap-grinding might not thread into today’s threads. Over their 125 years, the brass surfaces had become begrimed with dust mixed with sea humidity.

Thin films of recent hydrocarbon soot and rubber tire particles lay atop a crust of amorphous corrosion. The original black-painted OTA and mount housings had been repainted with a dense lead-based gray coating, which had so badly crystallized that cracking the seal of screws sprayed splintery shards in our faces and all over our hands some simply refused to budge, even with a torch.

Figure 3: Stellar spectroscope (prism not in place).

Decades-old grease had oxidized so badly that it had lost its lubrication and transformed into a thick, sticky gum more like tapioca in Jell-O than emollient grease. The hand-machined screws, nuts, bolts, braces, and brackets required ultra-thin-blade screwdrivers available only from specialized hardware purveyors (at $49.99 for a set of 6!). The thread diameters, pitches, and face angles of 1891 relied on a now abandoned standard called the “RAS thread,” which corresponded to no other system in use today – Whitworth, Imperial, SAE, or Metric. Luckily, the glass of the objective showed no chips or surface scratches visible to the eye. There were small patches of seaweed-like hyphae mold that could be easily removed with alcohol. Yet even with this modest glimmer of hope, the overall picture was summed in a word: Bleak. No one in South Africa could undertake such a demanding – and costly – task. One look at this website, http://www.ulo.ucl.ac.uk/telescopes/fry/ , tells us why. Figure 4: Set of six Ottway eyepieces dating from the late 1920s. The author’s star test of these in his 7-inch Russian Maksutovs yielded up apparent fields of view ranging from 45° to an ab-stemious 18° and a paean of gratitude for computer-generated eyepiece design. give away the tale before the telling, Pepos was put up for international auction. To the rescue charged a hero named Daniel Mobati, a telescope restorer living in Oakland, California. His modern weaponry is screwdrivers and ratchet-wrenches in lieu of the more traditional dragon-slaying gear. He responded to Pepos’s plight with a proposition no damsel could refuse: “I will take you to my most beautiful land of the Napa Valley, and there I will build for you a magnificent observatory, where the world will come to see your stars. Your friends will be the Clarks, the Grubbs, the Brashears, and a sweet old uncle named Dollond. You will live happily ever after making the world as happy as you.” An Inauspicious Beginning The Port Elizabeth Cooke went by the name of Pepos, but it wasn’t always thus. She started life as the bottom of a broken whiskey tumbler found on a rubbish tip by a curious young man. He thought she might be perfect for his grand dream: A telescope to look at the stars and planets and moon. Figure 5: Cooke filar micrometer. The young man was Thomas Cooke, a cobbler’s lad born March 8 th , 1807, in the Yorkshire village of Allerthorpe. His formal education was two years in an elementary school before his father summoned him to the workbench. Thomas’ interests lay elsewhere. Inspired by the exploits of his namesake – Captain James Cook – young Thomas wanted to explore. He taught himself mathematics and navigation. At the age of 17 he was all set for a life at sea, but was dissuaded by a fretful mother to instead take up teaching at a village school. From 1829–1836, he taught local youngsters. He used his spare time to advance his studies in math, optics, and mechanics. Around 1832, Cooke made himself a small telescope from the bottom of a broken whiskey tumbler. Its tube was a sheet of tin. The telescope worked tolerably enough that it inspired local Yorkshiremen to “peer at the planets.” Thomas showed it to John Phillips, curator of the Yorkshire Museum and a member of the British Association for the Advancement of Science. Phillips encouraged Thomas to think bigger. At the age of 28, he made a 4.5-inch telescope using hard-to-get optical crown and flint and brass bought from his savings. He made it entirely by himself using knowledge he picked up in libraries. The telescope introduced Cooke to the much larger world of the British scientific community. Thomas was encouraged to embark on a full-time career as an instrument maker. He borrowed £100 from his wife’s uncle and rented premises in York. His wife Hannah worked in the shop and took in lodgers to help with the rent. He built his own screw-cutting lathe and lens grinding and polishing machines. Refractors of 4 or 5 inches were a rarity at the time and quite costly by our standards. His 4.5-inch was so optically successful that Cooke promptly pushed the boundary. In 1851, he built a 7.5-inch equatorial for Hugh Pattinson of Newcastle. Pattinson was a friend of Isaac Fletcher, a well-known astronomer who recommended Cooke to Sir George Airy, the Astronomer Royal. Figure 6: Price list from 1886 Cooke catalog. One £ sterling was equivalent to US$140.60 to-day

Young Mr. Cooke may have been a neophyte to the world of astronomy, but he was no babe in the woods in the fundamental requirement of modern manufacture: marketing. Witness the1886 Cooke catalog, shown in Figure 6.

To reduce the bottlenecks that hinder consistent product quality – unreliable suppliers and uncertain quality control – Thomas built his factory based on end-to-end flow-path production. Half a century later, Henry Ford called the same method an “assembly line.” Cold-rolled sheet iron, billet brass, and glass blanks arrived at one end. A diversified, self-consistent, high-quality product line emerged from the other.

Cooke perfected two virtues inherent in end-to-end thinking. One was standardizing the design of large assemblies, such as GEM mountings and gear-sets, which lowered unit costs. They were also scalable. One mount design could be used for many different optical tubes. Cooke’s no-frills 1850s German mount could carry OTAs with 6-inch to 12-inch f/15 objectives.

Figure 7 – State of the art: A deluxe model eight-inch Cooke refractor, ex-works, c.1885. Source: Cambridge Observatory Library.

A less-visible cost-control benefit was just-in-time control over small parts. A small-parts machinist would mill as many screws and bolts as the current pipeline demanded, then turn to gear cutting until the bolts ran low. The flip-side was slight mismatches in parts used in each successive telescope. Cooke also standardized the big bits: The 8-inch scope was over-mounted in the Port Elizabeth instrument, but not if the same mount held a 10-inch or 12-inch scope – precisely what Cooke intended.

Nipping at Cooke’s heels was Thomas Grubb of Ireland, likewise no loafer when it came to product proliferation led by quality control. He started off as a billiard table maker and ended up producing the largest telescopes of his time. By 1860, both names were a byword for precision. Cooke’s 1886 catalog listed five full pages of spectroscopes alone, comprising 101 different models. The United States was no slowpoke in producing its own rising stars, the forerunner Henry Fitz, trailed closely by Alvan Clark and John Brashear.

These telescope makers’ embrace of product diversity may sound like the Japanese SLR camera industry in the 1970s, but in fact, the late 1800s manufacturers were following an already well-trod path. In the 1770s John and Peter Dollond produced somewhat standardized telescopes of many varieties and prices, plus sextants, octants, theodolites, and surveying instruments. So did Robert-Aglaé Cauchoix and Georg Merz & Sons of France and Joseph von Fraunhofer and Georg Friedrich von Reichenbach of Germany.

All of these were legatees of the European Enlightenment’s emphasis on logic over tradition. Not to mention economics above ecclesiastics – the likes of Fraunhofer, Cooke, and Grubb were not so foolish as to forget an affluent merchant class buys more opera glasses than a lordly ruling class.

The 19 th century has been called “The era of the Grand Amateurs.” Then as now, nonprofessionals made significant contributions to the science. In the 1860s, John Birmingham of County Galway, Ireland used a 4.5-inch Cooke refractor to study “red stars.” Birmingham logged 658 of them. This was long before the Hertzprung-Russell Diagram came along to show that many stellar processes could be bundled into the term “red.” The science of astronomy traced Birmingham’s beloved “garnet hued gems” to the opacity of carbon ash convected to the surface of helium core-burning stars – a process is unromantically described as “third dredge up.”

Figure 8 – Troughton & Simms, London, 1839 42-mm solar transit circle. Source: author pho-tograph.

Export markets were at the heart of colonial economic thinking. The Venus transits of 1882 and 1894 provided a ready excuse to ship small portable solar transits (Figure 8) to the nethermost islets the Empire to draw the time zones so the Empire’s Sun would never set. Transits were soon followed by theodolites and surveying chains to map the terrain. A few of these were literally set up on a beach table above high tide on a remote Pacific island.

The right telescope at the right time can redirect a career. In Bankura, India, one Chandrasekhar Venkata Raman used his 5-inch Cooke refractor to observe Saturn. The aspiring young mathematician wrote, “Not only was the Crepe ring an easy object, but for nearly one hour while the definition was perfect, I made out Encke’s marking in the A ring and held it steadily for practically the whole period.” Chandrasekhar reset his compass toward astrophysics. Early in the 20 th century, he mathematically modeled the energy physics of Type 1A supernovae and won the Nobel Prize in 1930.

Hobby Becomes Science

Cooke’s growing mastery of telescope making coincided with the merger of visual astronomy with exact science. In the late 1850s, Gustav Kirchoff, Robert Bunsen and William Huggins combined theory with observation to define the relations between chemistry, temperature, and the emission and absorption of light in gases. No sooner had the chemical composition of the Sun become known than the Cooke company added spectrometers (Figure 9) to their lengthening list of optical micrometers,

Figure 8 – Troughton & Simms, London, 1839 42-mm solar transit circle. Source: author pho-tograph.

Most of the affluent gentry who bought telescopes used them to map planetary features and systematize the measurements of double stars. Others, though, found new hay to winnow. In 1858, William Huggins had acquired an 8-inch object lens by the famed American optician Alvan Clark, paying some £200 for it (equivalent to US$28,120 at today’s rates). He then commissioned Thomas Cooke & Sons build a tube, mounting, and spectroscope for his intended use, stellar spectroscopy. The fact that starlight could be separated into constituent hues was known as far back as Isaac Newton. Only in the first few decades of the 19 th century did William Wollaston and Gustav Kirchoff notice that the dark absorption lines in the Sun’s spectra corresponded exactly with the bright emission lines recorded by Robert Bunsen in the spectra of specific chemical elements heated to incandescence. When William Huggins learned this, he constructed a modest two-prism spectroscope to observe the emission of planets and nebulae to learn what they were made of. Its dispersion was good enough to show that the Moon’s spectrum contained the same absorption features as the Sun. But there also were absorption bands of iron, manganese, and silicate compounds, which did not exist in molecular form on the Sun. He deduced that the Moon was made of the same stuff as the Earth, but the Earth added a few touches of its own. Today such “telluric” bands are deducted when they appear in stellar and nebular spectra. By 1864 Huggins could summarize one of astronomy’s fundamental theorems: “The entire universe is one chemistry.” Not content to rest on that laurel, in 1897, Huggins directed his Cooke spectroscope on a planetary nebula and on the Great Orion Nebula. He found not absorption or emission lines, but a continuous spectrum. “The riddle of the nebula is solved,” he wrote. “They are not an aggregate of stars, but a luminous gas blending many spectra.” He concluded exuberantly, “So unexpected and important are the results of spectrum analysis of the heavens, this method maybe said to have created a new and distinct branch of astronomical science.” Mr. Bently Makes Good Figure 10: Original RAS accession stickers found on the Port Elizabeth Observatory’s equip-ment boxes in 2015 were definitive proof of the telescope’s provenance leading back to the RAS inventory list, where item 148 states that it was shipped to “Ast. Soc. of S Africa Port Elizabeth, 1948”. Source: author photograph. When the owner of this fine 1891, 8-inch Cooke refractor passed away in 1911, the Cooke was bequeathed to the Royal Astronomical Society “to put it to good use.” (See Figure 10) The RAS catalogued it as Inventory Item RAS 148 on page 229 of the Royal Astronomical Society Instrument Collection 1927–1985 (Q Jl R. Astr Soc, 1986, 27, 212–236). ( 1986QJRAS..27..212H ) There it might yet be mouldering away, but for the interest of a tiny group of eight aspiring stargazers from South Africa. Unless it happens to be your birth year, 1947 is not noted for much. The word “computer” was coined in April that year to describe an electronic digital computational machine. In June, an American aviator named Kenneth Arnold made the first widely reported sighting of an unusual object flying near his plane. Unhappily for the cause of exactitude in science, it looked like a flying saucer. Measurement and misperception have competed for our allegiance ever since. In the somewhat sleepy postwar port of Port Elizabeth, South Africa, a Mr. J Bently had developed a keen interest in astronomy. He was once a fisher who navigated by the stars. When he looked up at night in those LP-free years, there was a lot up there to marvel. The Milky Way was so bright it cast the shadow of his hand on a white surface. On 28 May, 1947, Bently gathered twelve celestially minded colleagues to form an observatory society. Mr. Bently’s group was realistic about their ambitions: They borrowed a 4-inch refractor and an epidiascope used to project images of book pages onto a wall. That set a South African precedent that a proper observatory must have a lecture room in the same facility. Bently made inquiries at the Cape Observatory and learned that a large Cooke Refractor in storage at the Royal Astronomical Society in Britain might be available. The asking price was a pulse-quickening £1,200 (approx. US$40,800 today).

Figure 11: The Cooke’s first observatory was an open field. This method of solar observing is NOT recommended. Source: Nielen Schaefer.

By the standards of the time, that was a bargain. With astrophotography in the 1880s, the sands had shifted in the swirling tides of astronomy economics. The cost-vs-science yield inherent in permanent images and large-surface reflecting telescopes had turned most gentleman astronomers into gentleman racing horse owners. The word “astronomy” was understood to mean a fully equipped and staffed professional observatory, not a ATMer in the back yard, no matter how exotic their equipment.

Even so, the numbers of middle-class backyarders ascended dramatically, particularly in America, where DIY is as deeply ingrained as owning an automobile. The Second World War devastated global science budgets after all, entire nations needed rebuilding before observatories might be contemplated.

The cheerful enthusiasts of Port Elizabeth were affluent enough to pursue their love of the stars. Like so many early-adopters, they relied on hand-me-downs. They initiated a public fund-raising drive and within a year had garnered enough private and public funds to order the RAS Cooke. The name “Port Elizabeth Peoples Observatory Society” (Pepos) is a fitting amalgam in honor of so diverse an array of open wallets.

Their glorious new Cooke refractor arrived in two enormous crates in mid-1949. The world was large and getting larger. That same month the packet HMS Pamir was the last commercial sailing ship to round Cape Horn under sail alone. Fred Hoyle coined the term “Big Bang.” The City of Port Elizabeth generously opened its purse to the tune of £2,000 to build a roll-off-roof abode for their pride and joy. By June 1953, PEPOS Committee deemed the equipment, observatory and personnel had been finely honed enough to open the telescope to the scrutiny of all South Africa.

Shown here is the text from the article that appeared in THE HERALD NEWSPAPER in Port Elizabeth, Eastern Cape June 29 1953:

Public Can Peer at the Planets Through City’s New Telescope

The only large astronomical telescope to be set up solely for the public use in South Africa is to be opened to townspeople and visitors to Port Elizabeth on Wednesday night.

Officers of the Port Elizabeth centre announced yesterday that, weather permitting, members of the Society would be in attendance every Wednesday night, starting this week, to enable small parties of interested people to look at the planets. The telescope is the only large professional telescope to be set up solely for the benefit of the public in South Africa.

Only one month earlier, on May 3, the first commercial jet flight service commenced between South Africa and Britain began with the arrival of a De Havilland Comet with 36 passengers at Johannesburg.

During the opening-day festivities, Mr Bently addressed the visitors: “It is my sincerest hope that South African amateur astronomy might one day produce its own William Herschel.” Bently may well have had in mind Lindsay Atkins Eddie (1845 – 1913) a native-born amateur astronomer from Grahamstown, who observed 21 comets and the Mercury transit of 1894. His drawings of the planet Mars were highly acclaimed in the world of planetary astronomers.

South African astronomy had roots as far back as the eighteenth century visit of Nicolas-Louis de La Caille to chart the positions of the southern stars. The 19 th and 20 th centuries brought William Herschel and his 18-inch speculum reflector, the 74-inch Radcliffe reflector in Pretoria, and the Cape Observatory’s fanfare of instruments, which included the renowned 24-inch McClean Refractor (now gleamingly restored to its original condition).

Illustrious names in the annals of astronomy either were born or spent considerable portions of their lives in South Africa. Their papers peppered the professional literature. The double stars which so preoccupied gentlemen astronomers of the late 19th century were not forgotten. Willem Hendrik van den Bos discovered thousands of double stars and recorded tens of thousands of micrometer measurements of such stars, calculating the orbits of a number of binary stars.

At the other end of the megaparsec scale, Anthony Patrick (Tony) Fairall specialized in the large-scale structure of the Universe revealed in filaments and voids. The QSO Fairall 9 is so important that it is still cited in Magellanic Cloud studies. William Cousins, South African by birth, devoted himself so assiduously to improving photometric methods that his UBVRI color photometric system standardized spectral colors used to determine the metallicities of stars and nebulae his work was a major factor in turning the static Hertzsprung-Russell Diagram into today’s Colour-Magnitude Diagrams (CMD).

When the Cooke telescope was offloaded onto a Port Elizabeth dock in 1948, South Africa’s leading astronomer was Andrew David Thackeray (1910 – 1978). He directed the Radcliffe Observatory for 23 years, specializing in stellar spectroscopy. As Port Elizabethan eyes trained on the southern skies through the Cooke telescope for the first time in 1950, Thackary published his first studies of dense, inky dark “globules” that he had spotted in the Eta Carinae complex. He suggested that the interplay of supersonic turbulence, magnetohydrodynamic forces, and gravitation wrote the rules of star formation in chaotic, hot gas structures. This was the first time so many complex physical forces had been discerned at work in one group of very small objects.

Not to be outdone by his own feats, in 1952 Thackary presented studies of variable stars in the Magellanic Clouds which suggested that the age and size of the universe as then understood was in fact too young and too small by half.

All this would have swelled the chest of Sir David Gill, HM Astronomer at the Cape from 1879–1907. Gill was a masterful administrator and visionary. His vision of bringing forefront science to South Africa set the direction of South African astronomy for decades. His seedling bore spectacular fruit when the Astronomical Society of South Africa was appointed the monumental task of overseeing the Square Kilometer Array (SKA), which will be the largest radio astronomy centre in the world.

Not farewell. Fare forward

At its peak in the 1980s, the PEPOS sported 81 members. But starting in the 2000s, there was an inexorable decline. Aging was part of it, but more so was light pollution. Once sited in a solitudinous meadow, the Port Elizabeth observatory is now ringed with suburbs ten miles in every direction. Fast food restaurants and mini malls clog the road only a block away. The same thing happened to the observatories in Cape Town and Bleomfontain. But while the professional community had the resources to move their equipment to an excellent remote site in Sutherland, not so fortunate was Pepos in Port Elizabeth.

The historic Cooke telescope was less and less visited. The Port Elizabeth Astronomical Society faced the vexing problem of what to do with a deteriorating telescope in a location with dismal skies. Some members were all for selling it off as scrap metal and be done with it. Wiser heads prevailed.

The most far-sighted was Nielen Schaefer, a long-standing Society member and devoted observer. Mr. Schaefer enlisted a small group of individuals to seek a solution – Ms Kate Cobbing, the professional astrophysicist Case Rijsdijk, Rhodes University professor Marc Schafer, and this author. Initial attempts to find a home for it in South Africa found no one with the experience, wherewithal, and desire to restore such a complex piece of equipment.

Figure 12: What two 70-year-old South Africans can do to a priceless telescope with a screw-driver, crescent wrench, and hay-bale winch.

Then this author came across the Antique Telescope Society, a worldwide forum of some 883 members whose great avocation in life is to put back into use historically priceless astronomy equipment. After a flurry of correspondence with the ATS President Bart Fried, a plan gelled to set up an international auction designed to attract the most qualified historical instrument restorers in the world. The auction took a month. The applicants were few but they presented collecting histories that included prestigious names like Clark, Brashear, Fitz, Fraunhofer, Grubb, and of course, Cooke.

On 28 October, 2015, PEPOS announced that the highest bidder for the 1890s Cooke was Daniel Mobati of Oakland, California. Mr. Mobati was chosen as much for his intentions as for the amount of his winning bid. In his own words: “It would indeed an honor to be the next custodian of this observatory. My plans include restoration and preservation of all the instruments which will be housed on an observatory in the San Francisco Bay Area. The specific location will be in Napa Valley, in the heart of the Wine Country. I hope it will be instrumental in providing access to the interested public (specially the youth generation) with the goal of educating and sparking an interest in the history and the science of Astronomy.”

Figure 13: The damsel saved. Next stop, a two-year restoration, followed by a new home every telescope owner could only wish was their own.

By the end of 2015, Nielen Schaefer and this author had stripped the Cooke telescope down to crate-able size pieces ready for shipping to the USA (Figure 13). In July 2016, the magnificent telescope was loaded into a container in Port Elizabeth. One month later it was offloaded from a semi-trailer truck in Mr. Mobati’s driveway.

This story couldn’t have been told without acknowledging the role of amateur astronomy in the USA. The spectacular success story of amateur astronomy today had its roots in American middle-class affluence after World War II. To the world at large, only in 1957, with the Moonwatch Program, did backyarders become Everyman astronomers.

Throughout the last half of the 20 th century and well into this one, science has delivered more betterment for humanity than politicians. Now in the mid-2010s, the simultaneous achievement of generalized wealth and the

Figure 14: Antique telescope restorer Dan Mobati with his newlywed wife Marcela at their wedding party in October 2015, the same month he successfully bid on the 1891 Cooke Refrac-tor in faraway South Africa. With them is Marcela’s niece and bridesmaid, Shirin. Source: Daniel Mobati.

technology of mass production has given us an astronomy world no one could have dreamed until now.

Where once there was a Cooke, a Grubb, a Clark, a Brashear, or a Merz to choose from – all of them prohibitively dear to the average buyer – today’s lover of the skies has a veritable bonanza of product catalogs to choose from at prices for every budget. Not to mention the classifieds, the clubs, the star parties, the online forums, and thousands of astrophotogaphers churning out images that would have astonished Palomar astronomers just a decade ago.

Mr. Mobati summed up this whole tale better than anyone: “Why look backwards for a Golden Age when we live in one?”

The Astronomy Technology Today editorial staff would like to take this opportunity to remind you of the availability of our Solar eclipse equipment guide – The Definitive Equipment Guide to the 2017 Solar Eclipse. Our goal with the 40 page publication is to provide an easy-to-consume introduction to the technological options for viewing and imaging the Great Solar Eclipse. We cover the gamut of options available including building you own solar viewer, solar glasses, smart phones, DSLR cameras, using astronomy telescopes, solar telescopes, using binoculars, solar filters (including a DYI filter option), CCD astro cameras, astro video cameras, webcams and much more. You can view the guide on our website here – its free and there is no requirement to sign up to read the guide.

## Stabilizers/dampers for refractor telescope - Astronomy

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