A Work Dedicated to the Faithless Generation
If men could learn from history, what lessons it might teach us! But passion and party blind our eyes, and the light which experience gives us is a lantern on the stern which shines only on the waves behind.
Samuel Taylor Coleridge (1772-1834)
The first glance at History convinces us that the actions of men proceed from their needs, their passions, their characters and talents; and impresses us with the belief that such needs, passions and interests are the sole spring of actions.
Georg Hegel (1770-1831)
Who loves, raves.
Lord Byron (1788-1824)
Culture: some definitions
The quality in a person or society that arises from a concern for what is regarded as excellent in arts, letters, manners, scholarly pursuits, etc.
A particular form or stage of civilization, as that of a certain nation or period:
Development or improvement of the mind by education or training.
1733: Chester Moore Hall combines crown and flint glasses to create the first achromatic objective.
1758: John Dollond patents the design and begins commercial production of achromatic telescopes. In the decades that follow, these compact new instruments greatly aid mankind in matters as diverse as navigation, surveying, leisure and military applications.
1814: The brilliant German optician, Joesph von Fraunhofer, identifies 560 spectral lines in the solar spectrum using a small achromatic refractor of his own design, thus establishing the powerful science of spectroscopy.
1824: Herr Fraunhofer, having developed new ways of making high-quality achromatic lenses, builds the largest telescope in the world, The Great Dorpat Refractor, and mounts it on a state-of-the art equatorial mount with clock drives. The instrument revolutionises professional astronomy. F.G.W Struve uses the telescope to conduct his grand survey of double stars, discovering 3134 new pairs.
1829: Johann Heinrich von Mädler, using a 9cm Fraunhofer refractor, constructs the first map of the planet Mars.
1834: With the same telescope, Mädler and Wilhelm Beer complete the first exact map of the Moon.
1838: The German astronomer Friedrich W. Bessel uses a modified Fraunhofer achromatic objective of 6.2″ aperture to establish the parallax of the star 61 Cygni, thereby elucidating the mind boggling distances between the stars. Recognising its significance, Sir John Herschel said of Bessel’s work;
[It is] the greatest and most glorious triumph which practical astronomy has ever witnessed.
1844: Admiral W.H. Smyth publishes his Cycles of Celestial Objects.
1846: The outermost planet, Neptune is tracked down and confirmed to exist with an equatorially mounted achromatic refractor by Fraunhofer.
Carl Zeiss of Jena, Germany, founds his optical company.
1847: Alvan Clark of Cambridge, Massachusetts, USA, establishes his telescope making business.
1851: George Biddell Airy installs a new achromatic transit circle at Greenwich (8 inch f/17 specification). Work with this instrument establishes the Prime Meridian, dividing the world into Eastern and Western hemispheres.
1855: Thomas Cooke of York, England begins building fine refracting telescopes of ever increasing size.
1857: Jesuit priest and astronomer, Angelo Secchi, employs 16.5 and 24.5cm achromatic refractors at the Collegio Romano, Rome, to conduct the first visual spectroscopic survey of the stars, allowing him to subdivide stars into four spectral classes.
1864: Using an 8-inch Clark refractor, English amateur astronomer, William Huggins solves the riddle of the nebulae. On the night of August 29, his diary records, “I turned the telescope to a planetary nebula in Draco (NGC 6543)…. I looked into the spectroscope. No spectrum such as I expected! A single bright line only!” Huggins had shown that this was not an unresolvable grouping of stars, as was widely believed, but a gaseous object.
1867: Having used a number of fine achromatic telescopes, the eagle eyed British observer, William Rutter Dawes, establishes his so-called Dawes Limit in regard to the resolution of double stars. That visual limit is still the best empirical formula available to astronomers today.
1868: British amateur astronomer, Richard A. Proctor, publishes his highly popular astronomy text: Half Hours with the Telescope. The book is written around what can be seen in a modest 3-inch achromatic refractor and is very well received by a growing number of amateur astronomers across the British Empire.
British amateur astronomer, Norman Lockyer discovers helium using a fine 6″ Cooke refractor.
1870: S.W Burnham acquires a 6 inch Clark refractor to begin a systematic survey of double stars.
1873: Burnham publishes his first work. An article appears in the Monthly Notices of the Royal Astronomical Society entitled, Catalogue of Eighty One Double stars discovered with a six inch Alvan Clark refractor. It is a stunning piece of work by anyone’s standards and establishes him as the greatest double star observer in history.
1877: Asaph Hall, staff astronomer using the 26-inch Clark refractor at the U.S. Naval Observatory, discovers the two tiny asteroid moons of Mars – Deimos and Phobos – during the August opposition.
The same instrument is still in active service.
1880: The great era of planetary study is in full swing, with essentially all of the lunar and planetary features sought out by amateurs today having been discovered and characterised by skilled observers using the classical refractor. Bolstered by the bogus theory of Darwinian evolution, some notable astronomers – Schiaparelli & Lowell in particular – sensationalize the planet Mars as the likely abode of intelligent extraterrestrial life. Other observers of note; the Christian astronomer, Edward Emerson Barnard, in particular, express scepticism about these claims, calling for intellectual restraint in making such audacious remarks.
Pennsylvanian, John A. Brashear, founds his optical company.
1886: The French brothers, Pierre Paul Henry and Mathieu Prosper Henry, produce the first photographic images of Jupiter and Saturn through an achromatic refractor of their own design.
1891: The Henry brothers and Paul Gautier complete the Great Meudon photovisual refractor. With an aperture of 33 inches and a focal length of 53 feet, La Grande Lunette becomes (and still remains) the largest refractor in Europe.
1892: E.E. Barnard uses the 36-inch Lick refractor to discover the tiny (mean radius 83 kilometres) Jovian satellite, Amalthea – the last satellite to be discovered by visual means.
1897: The largest refractor in the world, the 40-inch at Yerkes Observatory, William’s Bay, Wisconsin, sees first light. The limitations of the refractor design are reached, causing all future telescope builders to consider larger reflectors over their refractive counterparts.
1900: S.W. Burnham publishes his magnum opus, A General Catalogue of Double Stars, consolidating the prestige of the classical refractor in the noble pursuit of double star astronomy. A veritable treasure trove of truth, 1290 new pairs are documented.
1909: New observations made by the world’s foremost visual observers, E.M Antoniadi, using the superior resolving power of the 33 inch refractor at Meudon, France, and the work of E.E. Barnard, working with the largest refractors on the planet in America, disprove the fanciful canal theory of Lowell, suggesting that they were instead optical illusions.
In the same year, the American amateur astronomer, William Tyler Olcott publishes his, In Starland with a Three Inch Telescope.The work becomes highly popular among amateur astronomers equipped with a small classical refractor, across the literate world.
The three inch refractor proves especially popular with the ‘gentleman astronomer,’ like this model, owned by Albert Einstein – a telescope he brought with him to America from Germany.
1911: Leading British astronomer, T.E.R Philips, pays a visit to Meudon Observatory, Paris, where he describes the view of Jupiter though the great telescope.
1912: Using the 24 inch refractor at Lowell Observatory, Arizona, Vesto M. Slipher obtains spectra of some nearby galaxies and in so doing notes that their spectral lines are shifted toward the blue end of the spectrum (for M31) or (for other galactic neighbours) towards the red end of the visible spectrum. Thus, Slipher discovers the phenomenon of the ‘redshift’. More spectra obtained with larger reflectors lead Edwin Hubble to enunciate that the Universe is expanding and is therefore not eternally old as was widely believed. The cosmos had a definite beginning in space and time.
1918: Robert Grant Aitken publishes his book, The Binary Stars, in which he announces that the Lick refractor could resolve equally bright pairs down to an incredible 90 milliarcseconds. He offers a new formula for these pairs; 4.3″/a beating the Dawes formula 4.56″/a, where a is the aperture in inches.
1925: American amateur astronomer, Leslie Peltier, uses his 6″ f/8 achromat, a.k.a the Comet Catcher to discover his first comet. Peltier would go on to use the same telescope to discover many more variable stars and comets
1933: British actor and amateur astronomer, Will Hay, uses his 6″ f/12 Cooke refractor at his home observatory in North London to discover Saturn’s Great White Spot.
1946: Walter Scott Houston begins writing a monthly column on deep sky observing for Sky & Telescope magazine. Houston employs his favourite instrument; a 4-inch Clark refractor, to view the majority of objects he showcases in his Deep Sky Wonders, which he continued to write until his death in December 1993.
1954: With World War II over, the US Optical company Tanross (later Tasco) is established as a major importer of fine Japanese optics. Many amateurs cut their teeth with beautifully crafted 60mm refractors but their larger aperture refractors remain prohibitively expensive for most.
1960: Fuelled on by the Space Race, many new optics houses emerge offering the amateur finely crafted lenses. High quality achromatic refractors are marketed by Swift, Unitron, A. Jaegers, Sears, Mayflower and( the much older) Broadhurst-Clarkson.
1981: Stephen James O’ Meara uses the 9 inch Clark refractor at Harvard College Observatory, MA, to make the most accurate timing of Uranus’ rotation period before the arrival of Voyager 2.
1987: D&G Optical, Mannheim, Pennsylvania, begins production of fine achromatic lenses and complete telescopes.
2004: The first econo-ED refractors are heavily marketed which promise to take the observer ‘to a whole new level of experience’. Nothing new is actually revealed with these telescopes however and yet the consumer is forced to pay more and more to receive less and less.
Interest in achromatic refractors begins to wane, despite huge strides to reduce the cost of their production. Advances in computer optimised production techniques offer the amateur finely figured achromatic lenses that are generally superior to the finest ‘antique refractors fashioned by the famous 19th century opticians and at a price that almost everyone can afford.
2005: Dr. Mike Palermiti, a professional in the field of optics, publishes a short article where he stresses that the use of expensive exotic glasses in apochromatic refractors is completely overkill for visual use and that skilled observers have no need to over indulge. His advice is ignored by the consumers of fancy glass.
2010: The lead author publishes his book on refractors, raising awareness amongst the amateur community of the importance of achromatic refractors that had satisfied their users for decades and centuries.
2011: American observers, John Nanson and Greg Stone launch their superlative website, Best Doubles, dedicated to visual double star observing. John, a.k.a, Der Admiral, employs classical refractors of various sizes in the pursuit of his colourful celestial booty.
2012: An ornate, all-brass refracting telescope, fashioned by master British instrument maker, I.R. Poyser is chosen as the principal gift to the citizens of Japan from the British people to commemorate four centuries of friendly diplomatic relations between the two countries.
The lead author uses his Astrophysics Traveler to satirise the state of affairs in amateur astronomy.
A thriving online community of amateurs – observers and collectors – maintain an active presence discussing the charms of the classical refractor. Many more amateurs begin collecting these precious instruments from yesteryear for pleasure.
A Spokesperson for the US Naval Observatory explains why the classical refractor is still the best choice for double star astrometry.
Sky & Telescope favourably review a very fine 102mm f/11 achromat by Astrotelescopes – the first such review in over a decade.
The Oddie II Telescope, featuring a modern achromatic lens, is reinstated on Mount Stromlo Observatory, Canberra, Australia in the aftermath of a terrible bush fire.
The Celestron C102 4-inch f/10 achromat goes on sale for less than $100. In a frenzy, many savvy amateurs acquire one and almost universally report excellent image quality.
Restorative work begins on Lowell Observatory’s historic 24-inch Clark refractor.
2016: The lead author sets to writing his new book: Tales from the Golden Age.
The lead author looks back on the rise in popularity of the achromatic and, with great personal satisfaction, sees that it is good.
My Favorite Telescope
by Terra Clarke, Kentucky, USA
I’ve collected quite a few classic telescopes over the last few years since I retired from a career in higher education. So when I was asked to write an essay on my favorite telescope, I briefly found myself in something of a quandary over which telescope to write about.
My collection initially came about quite by accident, or what Jung would call, synchronicity. I had just read an article in an astronomy magazine extolling the virtues of the classic 60mm long focus achromat. That had set me to thinking that I really would like one to complement my modern 80, 102, and 120mm refractors. (A 60mm refractor was the first telescope I had ever owned.) Then, while I was out of town, my partner called me on my cell phone to tell me that she found one for me at a thrift store. It was a 60mm equatorially mounted Monolux in its original wooden cabinet, and it was waiting for me on the dining room table when I came home. It was very dirty, but almost totally complete. It just needed a good cleaning and a couple of easily replaceable parts (dust cap and visual back). When I cleaned it up, I saw that it was a real beauty, made by Royal Astro. We set it up in a corner of the dining room a display scope, but we soon found that the scope performed wonderfully out on the deck under the stars. Small, lightweight, and very functional, it was a perfect grab and go telescope, ready to exit the kitchen door in an instant. It put up picture-perfect, defraction-limited views.
There is much to recommend in these old classic achromatic refractors. Aside from their beautiful craftsmanship they typically have excellent optics and near apochromatic like performance. They deliver crisp images of superb contrast; stars look like diamonds cast on black velvet. Their extensive focal depth make it easy to achieve sharp focus and excellent performance can be attained with simple eyepieces (orthoscopics, Plossls, Kellners, Erfles). Showing pinpoint stars and sharp well defined Airy disks; they are a delight to use under conditions of poorer “seeing” and light polluted skies. They are quick to achieve thermal equilibrium and are wonderful for instruments for viewing double stars, planets, the sun and moon in an urban environment.
That 60mm Monolux wet my appetite for another, larger classic telescope and in a short time a beautiful near mint, complete, 3 inch Sears just fell into my lap for very little money. I had wanted a scope like this when I was young and now, many years later, was my chance to get one. That is how I began as a vintage collector. I had always loved Unitrons so the 60 mm and the 3 inch were added next to the collection. Of course, no collection could be complete without a Zeiss, and when I found a nice Telementor T1, I acquired it as well, and then a T2. At this point, I could see that I had not one hobby, but two. I was not only an amateur astronomer, but also a telescope collector. I found a little 80mm Unitron spotter in great condition, at a great price, and I already had a spare Unitron alt-azimuth mount for it, and so I got it. Then another 60mm Unitron, (a very early one) came my way, and ultimately a fantastic old Unitron 4” equatorial, which I had the amazing good fortune to receive as a gift from a wonderful and generous person that I met through the hobby. Over the past several years a fairly rare 3” refractor made by Goto Optical of Japan in the 1950s and a classic Edmund 4” F15 refractor have come my way as well. I love little 60mm refractors, and with limited storage space, they don’t take up much room so when I found a complete little 50-year-old Tasco 60mm, wooden cabinet and all a thrift store for 20 dollars I picked it up. Most recently a very lovely, and totally complete 60mm Swift telescope in nearly mint condition was found while on an autumn weekend trip several states away.
Most of these telescopes came to me serendipitously. It was almost as if they had chosen me, rather than I choosing them. Often I made friends in acquiring them. I learned their stories. In some cases, we took long road trips to get them. But the most amazing journey of all was when the first telescope I had ever owned came home.
The 50s and 60s were such a great time to grow up. It was the “atomic” age, we were in the middle of the space race, it seemed like there was a different science fiction movie to see every week, and if you were a kid who loved science, these were heady times indeed! We even had a bright comet. I will never forget Comet Ikeya-Seki back in my first astronomy winter of 1965. In the 1960s everything was analog, we appreciated what we had, and we made the best use of it. We learned the night sky, learned to find what we wanted to see by star-hopping and using binoculars and star charts, and sometimes using setting circles. If the scope was driven, it was typically only in R.A. We looked in awe at the astronomical object we saw rather than critiquing the view with regard to chromatic aberration, pinpoint star patterns across the field, etc. And I should add that in my opinion anyway, the skies were much better then, fewer contrails, and less light pollution. It seemed to me then that is was much more about the sky and much less about the equipment- or perhaps that was just the exuberance of youth and living in the “space age.”
I had gotten interested in astronomy when I was 14 when one summer evening we went to visit some family friends who lived in the mountains of Southern California near where we lived. We were there for dinner and their son, who was about my age had a 3″ Edmund reflector. (The Space Conqueror I believe). After dinner, we went outside to look through it while the parents visited. From that point on I was looking up. I got a copy of the little Golden Book, The Stars, by Zim and by October, I had talked them into getting me a pair of binoculars, some Japanese 8x40s that my dad ordered from one of his sporting goods catalogs. I also got a copy of The Stars by H. A. Rey and I was off and running. At Christmas I got the Peterson Guide and by the following birthday, I got my first real telescope. It was a Japanese-made (APL) Mayflower 60mm x 700mm yoke-mounted alt-azimuth refractor. I got it in 1965 for my 16th birthday. I had wanted a 60mm Unitron alt-azimuth refractor (Model 114) but that was out of the question, the Mayflower cost about half as much at our “big box” store back then and we were a union, working-class family. I remember that crisp October night many years ago like it was yesterday. I even remember it was a Saturday. I was not disappointed! The first thing I looked at was Saturn! Then I split the “Double-Double” as Lyra was going down. I stayed up late to see the Andromeda Galaxy, the Hyades, the Pleades, and then the Orion Nebula and the Trapezium! Zowwie! I was in love! I was hooked on Astronomy for the rest of my life after that. I even also saw my first comet with that little telescope two months later; Comet Ikeya-Seki in December of 1965.
That little telescope knocked around with me for what seemed to be forever. I always kept it because the tube was built like a tank and the objective was superb. Over much of that time it was often my one and only telescope. It is very portable and presented amazing views for its aperture. The Mayflower always stayed in its box when it wasn’t being used so it remained in good shape and was always ready to go, and go it did. It was the family scope, the travel scope, the grab and go scope for over 30 years. My two daughters grew up with it. With it we saw solar and lunar eclipses, comets, the transit of Mercury, and the S-L impact scars on Jupiter. I indoctrinated my two girls with that telescope to the point that one of them, now a filmmaker has made an astronomy themed Sci-Fi short film and the other one named her son Orion. Oh the memories that scope holds! The wooden box and the wooden tripod legs had been refinished a time or two due to all the use, The tube has had to be touched up, but it is still dent and ding free; the optics pristine.
Eventually I got a couple of more modern refractors of greater aperture and the little scope got less and less use. Then, about 10 years ago in one of life’s upheavals, I loaned the Mayflower to some good friends and moved out of town. Up until a couple of years ago, I thought it was gone for good. Then strangely I received a phone call from the friend that I had loaned it to. She said she had run across it in her attic, that it was unused and unneeded and was calling to ask about its disposition. I asked her if I could swing by her place the next time I was in town and get it, and she said sure. So the little telescope came home. It was kind of a sad sight. The old yoke mount that had been showing its age for some time was finally shot. The gear housings for the worm gears were broken. The tiny finder was gone, so was the accessory tray. But optically, it was still perfect; the 0.965” eyepieces, diagonal, and other accessories were still present, and the tube and focuser, the wooden box and legs still in good shape. I resolved to put it back in good order.
I had some rings and a mounting plate made for it, and I bought a Unitron alt-azimuth mount, tripod and spreader from a friend and member on here. I also still have a vintage GEM that I bought from Edmund Scientific Co. a year after I got the Mayflower. I have placed that mount on the original Mayflower legs so my little first telescope can ride on this mount too, just as it sometimes did, many years ago. I also put a 6 x 30 finder on the little Mayflower that was way better than the tiny original, and I added a 1.25″ Vixen visual back so that it can use a larger prism diagonal and 1.25” orthoscopic, Plossl, and Kellner eyepieces. I use the little telescope a lot these days for quick solar viewing out on my deck. Recently I was using it to view sunspots with a 1.25” Intes white-light solar diagonal. It held at 93X just fine with a 7.5 mm Plossl eyepiece. Not bad for daytime seeing.
I lost my parents in 2000 and 2001. That Mayflower is especially important to me for that reason. Sometimes, it just takes a while to realize the true worth of things, but as my mentor in grad school used to tell me, “to soon we get old, to late we get smart.” I once threw it over (euphemism) for a 4″ fluorite Vixen, which is now long gone. If someone now offered me the Vixen back in return for the Mayflower, I’d have to say no. The little telescope has gone through some changes, but it is still basically the same little scope with that wonderful APL objective that I have seen so many wonderful things with over the years. And yet, it’s far more than just a telescope. It’s a talisman and a time machine. I will always remember my mom coming out from the kitchen to the backyard to take a look at what ever I was looking at. I can use it now and see her standing right beside me. It will be the last scope I ever let go. Yes, I thought I had lost it but got it a few years ago. But I never realized just how valuable it was to me. I do now, and when I got it back, I vowed it would never again leave me.
For me, it puts me in touch with those feelings and memories of what things looked like, felt like that first autumn and winter nearly 50 years ago when I first saw Saturn’s, Jupiter’s cloud belts, Venus in a crescent, the sparkling Pleiades, the distant Andromeda galaxy, and the glow of the Orion nebula through a telescope as a kid. Its pure nostalgia, and appreciation for the past becomes more and more important to me as I advance into the future. Sure I have modern telescopes (which if I admit it) present better views maybe, but they don’t give me the same feeling when I look through them.
All telescopes are time machines in that they allow us to look back into the past as we span distances across our galaxy and beyond. But classic telescopes are real ‘way-back machines’ that put us in touch with long past amateur and professional astronomers who discovered so much when looking through these elegantly simple instruments; and they put us in touch with our own past as well. For me, when I look through the “little telescope that could”, I am again that 14 year old kid that gazed through the telescopic looking-glass and was filled with wonder and awe. And I can here my mom softly whisper in my ear: “My oh my, just look at that!”
The Visual Virtues of Long Focus Achromatic Refractors
by John Nanson ( Der Admiral), Oregon, USA.
It took me a few too many years to discover the visual magic served up at the eyepiece end of a long focus refractor. Like many others, I was pulled toward expensive short focal length APO’s, primarily because they’re widely advertised, and also because for many years the vast majority of on-line comments about achromatic refractors was negative. Once I got my hands on my first achromatic doublet, a used 80mm Stellarvue Nighthawk that was built like a tank and weighed about as much, I discovered the constant refrain about the horrible CA affecting the visual image in an achromat was way off the mark. One double star observing session was enough to discover the filter I bought to lasso the out-of-control CA was about as unnecessary as a heat lamp in a desert at mid-day.
If I remember correctly, the SV Nighthawk was around f/7, so it doesn’t quite qualify as a long focus refractor, which for the purposes of this article we’ll define as f/10 or greater. Shortly after discovering an achromatic refractor wasn’t a metal tube of visual horrors, I came across an old 80mm Mizar refractor that was sporting a 1200mm focal length Carton lens – as in f/15. It didn’t take more than a few days for the telescope to find its way to my front door, secured in an old wooden box that felt like it was filled with lead weights. The one thing that scope lacked was a dew shield, so a trip to the local hardware store netted a piece of black PVC pipe that fit perfectly after some minor alterations.
A double star that was on my uncooperative list at the time was Theta Aurigae(magnitudes of 2.60 and 7.20 separated by 4” as of 2009), which I believe Neil had first mentioned to me. I had made several attempts to pry apart the primary and secondary with a couple of other larger scopes, but the seeing was so shaky and nervous each time that I never came anywhere close to succeeding. One evening shortly after dusk as Aurigae was hovering in the west, which typically is a rather turbulent part of the sky from my location, I pointed the Mizar tube at Theta just to take a quick peek. I really didn’t expect to see the secondary, but once I realized the seeing was remarkably stable, I increased the magnification until a dot of light budded into view on the rim of the primary. I stared for about fifteen minutes as that impossibly small dot of light clung to the primary as though it was afraid to let go. As the seeing deteriorated to its normal uncooperative self, I sat riveted in place at the eyepiece until the primary swallowed the secondary. I doubt a photograph would have done justice to what I saw, but it doesn’t really matter since the image is etched permanently into one of the many double star crevices in my mind. Since that time, I’ve cracked Theta Aurigae with larger scopes, but the 80mm Mizar view is still the one called up by my memory when I think of that double star.
Another long focus refractor that landed on my front porch is the Skylight 100mm f/13, also armed with a Carton lens. Whereas the 80mm Mizar was less expensive than the SV Nighthawk had been, the Skylight refractor represented a considerable investment. I hesitated on that one for that reason, but once I had it out of the box and on a mount, I became as attached to it as my right arm. It didn’t take long for the 100mm f/13 Carton lens to reveal its magic.
A double star that lures me back again and again is Rasalgethi (magnitudes of 3.48 and 5.40 separated by 5”), located south of the Hercules keystone. Tough it certainly isn’t, but beautiful it most definitely is. The primary is a rich orangish-red hue, and the secondary seems to be a toss-up between pale blue and pale green. I’ve looked at it more times than anyone can count, but the view I had in the Skylight f/13 on a night of better than normal seeing literally welded me to my chair. When I first looked into the eyepiece I was standing up, but as soon as my thirsty eyes drank in the image, I dropped into my chair and melted into it. Both stars were unusually sharply defined – as round as round can ever be — and etched into the black background like multi-colored slivers of glass brought to life by sunlight streaming through a stained glass window. I sat and stared so long I lost track of time. As each single scintillating second of that remarkable view soaked into my memory, I was very conscious of looking at something quite unique and special.
When I think of experiences like the two I just described, I conjure up images of S.W. Burnham sitting at his six inch f/15 Clark refractor. He discovered well over 1000 double stars with that instrument, more than a few with difficult sub-arcsecond separations, partly because he had eyes as sharp as an eagle, but also because he had a very capable instrument. And it was an achromatic doublet, too. Which is argument enough that an expensive triplet is far from necessary for either the casual or the serious visual observer.
When Life Takes a New Turn
by Rutilus, Yorkshire, England
For me, such a thing happened regarding my observing preferences and in particular the type of instrument I use. When I first started to observing the night sky with telescopes, I was using achromatic refractors. These instruments served me extremely well for many years. Then I caught the apochromatic bug which resulted in my purchase of a lovely102mm f/8 Triplet APO scope. I used the APO for around seven years, and was extremely pleased with it.
All appeared to show the same amount of detail as I was observing with my Apo ‘scope.Then, as if by fate, the opportunity to acquire a very well made 100mm f/13 achromatic doublet lens came my way. The lens was purchased and fitted into a tube and lens cell that I made myself. This achromatic scope was used extensively side by side with my APO scope. I was so pleased by the eyepiece views given by the achromatic instrument, I actually went ahead and sold the APO. The money from the sale went into a 150mm f/15 achromatic lens and heavy duty driven equatorial mounting.
When I started observing the night sky way back in the 1960s, the idea that one day I would own an excellent 6 inch refractor seemed nothing more than a pipe-dream back then.
Yet, here I am with such a ‘scope in my own back garden. Looks like I have gone full circle and starting to enjoy again the excitement of those early days.
The Story of Andromeda, my 5-inch D&G
by Dave Tinning, Central England
I have always loved long focus refractors and they don’t come much better than D&G American made lenses. The lens on this scope is pristine. The scope came from Osborne Optics in Newcastle, but I’m unsure whether this was a D&G built OTA or a UK built tube around the D&G lens. I suspect the latter is the case but I hope to ascertain for sure by contacting D&G themselves.
This ‘scope had been in storage for most of the past c12-13 years since it was bought by the seller. It has been securely kept in a large, robust shipping tube with the lens and focuser securely sealed. It has a few very minor marks on the tube but is essentially as new. It has a simple, but good quality and very smooth R&P focuser which can accept both 2″ and 1.25″ eyepieces. It came with a nice black 50mm finder but I have attached my own Stellar Vue 50mm RACI which I think suits the scope well.
My main concern was mounting the scope. My trusty CG-5 is a good mount but this is a very large OTA and really and truly it would be best on an EQ6 – something I can’t afford at this time; however, with the upgrades I have added to the CG5, including the ADM puck and saddle upgrade, and a longer counterweight bar, with a heavy duty WO mounting plate, the set up is more rigid than I could have hoped for. The OTA itself weighs only around 20lbs.
I almost sold this mount recently and am so glad I didn’t now! I hope you like the pictures and I will post a proper first light once I get one! I have high hopes of this scope for the bright planets and double stars.
In June 2014, I went to the Astro show in Leamington and met Mark Turner of Moonraker Telescopes. I had a good chat with him, especially about the focuser, and possible binoviewing. The standard Japan made R&P focuser was fine, quite smooth, but I always felt that the lens could take higher powers than I could properly use with the original focuser, with very fine adjustment being critical at powers of ~300x or more. Mark recommended the Moonlite range (in fact I’d had an old one a while back and knew that they are great units), and advised that he could machine me a new flange plate for the back of the OTA tube, so that a Moonlite dual speed focuser could be attached to it.
The other issue we discussed was in-focus. I knew that binoviewers could give great views, but the downside for me was always that they normally need to be used with a Barlow lens on a refractor. Since this is a long scope (1905mm focal length), even a 10mm eyepiece delivers x190 magnification, so the thought of doubling that or more with a x2 or x2.25 Barlow was not attractive to me. In the past I’ve always resisted chopping tubes to gain in focus; this time it was different. I felt that ‘Andromeda’ (as I’ve called the ‘scope) was worth the effort, and also as I get older, I know my eyes aren’t quite as good as they were years ago, and I just felt that using both eyes to view would be more relaxing and help me see more.
So, having all this going around in my head, I thought about it for some weeks and then decided to go for the focuser upgrade with Mark’s flange, to see how that was. I was genuinely delighted with the new focuser, but again in the few chances I had to use the scope with it, I still hankered to be able to use a binoviewer without a barlow. So I again spoke with Mark and decide to go the whole hog and send the whole tube (all c2metres of it! to him in London to completely revamp it for me. Here is what he did:
- Chopped 130mm off the tube and square off both ends to ensure the lens and flange would be completely square to the focuser.
- Drilled new finderscope holes either side of “straight ahead”, to allow the use of a finder on either side, or one each side, as I wished.
- Sent tube to powder coats to be stripped, repainted with multiple coats, including dewshield.
- Completely rebuilt new ray traced knife edge baffles (x3) with retaining rings and fit (the old ones were up to 10mm out of square alignment)
- Completely flock the whole tube with Protostar material, including the dewshield. It’s now like the black hole of Calcutta down there!
- Reshaped the base of Tal finder mounting bracket to fit the OTA perfectly
I received the tube back about 2 weeks ago and put her all back together again last weekend. I found a lovely vintage Yamamoto (Perl brand as sold in France) 60mm F6.6 refractor to use as a super finder, and it fits onto the Tal finder bracket perfectly.
For my first light, I turned to Saturn, a favourite object of most of us. Sadly, this year, it’s not been well placed, being rather low down: here in the English Midlands, although my local light pollution isn’t too bad, we are surrounded, within 10-25 miles, by a ring of large cities including Birmingham, Tamworth, Coventry, Leicester, Derby and Nottingham. So there is a ring of orange glowing around us in all directions, and I would judge that only the highest c40% of the sky is relatively dark and unaffected.
This means that Saturn was caught in that glow quite noticeably, but I have to say that, given that fact, the views were beautiful. A very clear Cassini division stretching all around the planet, a clear equatorial thick belt, and at least one other suspected at lower powers. I could also see two moons (I think Titan and Rhea) clearly, and another suspected.
Contrast was good, given the skyglow, and there was no glare from the planet, no light scatter, and no CA whatsoever.
I then turned to Delta Cygni, a favourite close double and not at all an easy split in anything less than a good 4” lens. In the D&G it was so easy! Clear, dark sky between the primary and it’s companion, (most of my previous views in 4” scopes tended to show the secondary sitting on the diffraction ring of the primary, but not here..). I also felt that the primary showed a suggestion of colour (very pale blue) which I had not noted before. All this bodes very well indeed for the scope to be a consummate star splitter!
Next up was the double double in Lyra, which by now was fairly high up. The striking thing here was the contrast, simply superb, with a jet black sky in my Leica Zoom at c x150, and two lovely double bulls’ eyes, each pair at right angles to each other.
Close by of course is Vega, that searchlight of the summer skies, and I wanted to see how much Chromatic Aberration would be visible: after all, this scope is an achromat. Well, I’m delighted to report that there is only the slightest tinge of violet from Vega; overall impressions are of an almost white, bright star with just a hint of violet which is actually quite pleasing. The same can be said of Deneb, in Cygnus close by, and even less obvious, since the star is not as brilliantly bright as Vega.
One of my favourite stellar quick view sights is Mizar in Ursa Major, and this one is truly lovely at low power in the D&G…(I should say here that “low power” is a bit of a misnomer here..at F15 with a 5” lens, the scope has a focal length of 1905mm, so my lowest power eyepiece, at 40mm is about x47 – not truly a low power experience, but as good as it gets with this type of scope. The contrast is what you notice with this scope, and the higher the magnification goes, the blacker the sky background gets.
The lunar surface is jaw-dropping in this instrument using the Baader Maxbrights and Takahashi LE 18mm pair.
This is not a deep sky scope, but, like anyone else, I will want to look at everything I can with Andromeda, and so I turned her to M13, the showpiece globular cluster in Hercules, on one of my all too short sessions: the high power nature of this long refractor actually enhances the contrast views you can get of quite small objects such as M13 in Hercules. Moreover, the Leica Zoom gives it’s widest field of view at higher powers, so I was able to view M13 at around x260, with a black background peppered with myriads of scintillating points of light which seemed just to pop up in ever increasing numbers, the longer I looked at the object. Truly beautiful!
The truth is, I don’t feel that, as yet, I have scratched the surface of this scope’s potential. I’m a happy chappy and so pleased to have Andromeda sitting, waiting, ready to cruise the heavens with me!
The Aesthetic Joys of Long Focus Refractors
by James Curry, St. Louis, Missouri, USA
My observing has evolved to the aesthetic presentation being “the all” of an evening’s time out. I enjoy a twilight setup of a long tubed refractor, its’ light collecting element well above the lingering ground effects. If I’m using a manual equatorial, first I get the scope carefully balanced with tube weights trimmed, mount clutches adjusted followed by a few star checks to see what the atmosphere is like. A walk around the scope is next, alternatively taking in the beauty of the instrument with glances skyward to monitor the firmament’s darkening. Taking my seat I glance around to be certain I have what I will need at hand; notepaper, pencil, light, etc. A few minutes for a 2 element achromat, perhaps twenty or so minutes for my 4 element Petzval to stabilize and I’m taking advantage of that atmospheric null time of steady air for solar system observing. Assuming a now stable weather system has ensconced itself over the region, this null time can vary in length but can stretch out to 2-3 hours. If it’s a good night 50x per inch is in store. Anytime I can reach above 50x per inch is a great night when observing from the middle of the continent. Truth be told, 125x – 175x is the normal maximum useable magnification for solar system studies no matter the aperture.
I spent decades with reflectors. My last one, a 10” Cave, sits forlorn in my man cave. Moving up the scale 4”, 8”, 12.5” I realized my sweet spot was in the 8”-10” range. I had a near religious experience on M42 with my 8” Parks during a cold winter’s session. But when it was time for a new scope I looked into the refractor market.
My first refractor was a Vixen 140 Petzval. Gone were the diffraction spikes, soon forgotten was the collimation issue and immediately noticed was the quick setup and temperature acclimation providing reliably steady views for an entire evening.
Tube currents became a forgotten malady. I took up the H400 challenge with this scope and methodically worked my way through it over two years. Fainter members of Markarian’s Chain, Stephan’s Quintet and brighter members of the Deer Lick Group and other challenge objects were checked off my observing bucket list with this scope. On nights of crystal transparency I was detecting galaxies to 13.5 magnitude, on nights of rock steady atmosphere Jupiter looked like hand painted calligraphy on the lens.
Next on my refractor journey was my 4” f/12 Istar build. 6 months or so of design combined with on-off shop time and I machined up the fittings to mate lens cell and focuser to my powder coat painted tube. The f/12 ratio seemed to provide a steadier, “smoother” image than the f/5.7 Petzval. Star testing it on its first night in public our club optical expert declared the lens “functionally perfect”. “This looks like it was turned on a lathe” he declared as he released the chair to anxious club members waiting their turn. The lens is advertised at 1/6 wave and he said it’s there.
Building on this initial success my follow-on project was a 6” f/12 build. Again, functionally perfect achromatic optics provide picture perfect views. Within minutes of first light I dialed in 300x on close double stars in Cassiopeia revealing perfectly concentric rings, clean hairline gaps and with the lens 7’-8’ off the ground an un-quivering view. One memorable evening in that early nightfall null of temperatures I was able to get a steady, detailed 360x on the moon.
Somewhere along this refractor journey I stumbled upon a 60mm Unitron rescued from the dump. Within a white tube permanently discolored by grease stained hands lay an optical treasure. This is the little telescope that could.
As a challenge one frosty winter’s eve I checked my Jupiter chart and realized there would be a double moon transit. I felt confident the shadows would be prominent but what amazed me was both moons remained in plain (concentrated) view for their transit duration. This experience whet my Unitron whistle and I’ve been on a quest to collect excellent examples of the 3” and 4” equatorials with a suite of accessories. While I still have a few, the 60mm-er’s no longer hold my interest for use observing.
Back to the aesthetic presentation theme. My 4” Unitron 155c is my “Venus” instrument, an object of admiration even set up in the house. Perfectly proportioned, I feel the Unitron line is the pinnacle of the amateur scientific instrument art. The 4” represents the largest portable scope of the line before you journey into the rarified air of the 5” and 6” observatory units. I have yet to meet an amateur astronomer whose head doesn’t swivel to the set-up of a 3” or 4” equatorial Unitron on the observing field. Even the “civilians” are irresistibly drawn to it at a public star party. The proportions are universally pleasing and the views will not disappoint. This is a telescope.
Further exploring the aesthetic theme, one summer’s eve I set up next to a 16”, high end, brand name Dobsonian. Almost immediately after the lens cap was removed my 4” was throwing up etched views of Saturn with its rings and Cassini division in sharp definition at 175x, about the limit for the atmosphere that night. The 16”, after having cooled with multiple fan assistance for an hour at that point, showed a smudged, current-smeared image with no shading on the disk and ill-defined rings. We packed up about 3 hours later after a heavy dew drop. That night the dob was all sob, it never produced a good planetary view plagued as it was by a mirror that would not keep up with the slightly falling temps. It could definitely reach deeper, showing fainter stars and out-resolve me on the globular clusters but those stars were not the pinpricks they were in the refractor.
A combination of a pleasantly proportioned instrument and those highly acclaimed refractor views are what I mean when I say I enjoy an aesthetic presentation.
by Bill Nielson, Florida, USA.
As a young child in the 1950’s I was fascinated with telescopes. I pleaded with my parents for a Christmas telescope. Sure enough one showed up under the Christmas tree and I remember it as my best present ever.
It was a humble, low priced Sears offering. A short tube 60mm achro with a Barlow and a sliding eyepiece that allowed 15x-60x magnification. I loved it! Showed a great blue enhanced view of the moon. The most blue moon I’ve ever seen. The CA was bad but I loved using it to observe the moon, birds, and terrestrial targets.
At around 11 years old I had a paper route and bought a Sears 60mm with a better mount and a much superior lens. Saturn was stunning, Jupiter too. The moon was no longer blue! This was my first quality achromat.
Bounce forward 40 years or so. After owning several scopes of different types I yearned for the simple pleasure of the telescopes of my youth and the ones I couldn’t afford at the time. So now I have four achromatic refractors that serve me well. I love the simplicity and the beautiful engineering of my Polarex (75mm) and Unitron (60mm) telescopes. I also have a classic 60mm Lafayette on a sweet, perfectly matched equatorial mount. I can pick this scope up with one hand and carry it outside,
Beauty, simplicity, quality, and great optical performance are what I enjoy.
Compared to APO’s, my ‘scopes stand up on their own considering price point.
I have other telescopes but my achromats are my favorite for visual, planetary, lunar, and double star observations. I use larger Newtonian reflectors for deep sky objects.
I live in a terribly light polluted urban area. The sky is milky white. However my long focus achromats deliver a dark background and near perfect star and planetary images which are very pleasing.
Some of the classics like Unitron/Polarex are collectable and demand a high price. They are highly crafted complete packages with superior mounts and accessories. They are worthy of display in any home. However there are many other small used achromats out there that are tremendous bargains. Some are almost given away at garage sales. Many have optics the equal to the expensive classics. But they usually come with less than desirable mounts. No worries, there are used and new mounts available to turn one of these great “finds” into a wonderful, cost effective telescope.
My 6” f15 D & G Telescope
by Andy Jackson, Perth, Australia.
About 20 years ago I became interested in telescopes and visual astronomy. I thought that telescopes were too expensive and difficult to get as there was only one local vendor and most Australian telescope shops were on the east side of the country. My sister visited Melbourne and was able to get a set of reflector mirrors for me. They allowed me to put together my first telescope, a 110mm f7.5 reflector. At that time I was into boat building as a hobby so I made the scope out of thin ply and Australian hardwoods. It worked well enough to show me the basic sights of the night sky and gave me a passion for wooden telescopes.
As this interest developed I learnt more about the differences between reflectors and refractors. I obtained a copy of Richard Berry’s book Build Your Own Telescope. I tried making other small reflectors and had a lot of fun. Eventually I began to lust after a good refractor. At the time I could not afford an apochromat and I had read good things about D&G achromat lenses available from the USA. I followed Richard Berry’s concept for the 6” f15 in his book and added my own touches based on my experience from making the reflectors.
The telescope that resulted from all this has proved to be an exceptional instrument. It is large and bulky but performs to a very high standard and is very basic and reliable. I have found it to be ideal for the variable conditions found here in Perth. It can be set up in a few minutes and is virtually maintenance free. It holds collimation and never needs adjusting. I like the fact that it will never need re-coating unlike the reflector mirrors. I still have an 8” Meade Newtonian mirror that needs re-coating however the cost of sending it to Sydney to be re-coated is more than the cost of a new mirror.
The 6” f15 performed so well that I got the bug and kept making more telescopes for fun. I have too many now and don’t have the time or space for all of them! I have also acquired some nice apochromats up to 4” f8 and enjoy using them especially when travelling as it is not so easy to transport a long bulky refractor.
During my ‘scope journey I have been inspired by many others that also enjoy the long focus achromat. Some great books include The History of the Telescope by Henry C. King and Epic Moon by William P. Sheehan and Thomas A. Dobbins
The Tasco 20TE Comes Back Home
By Mike Carman, Bellevue, Nebraska, USA
Every so often, the Midwest strikes a coupe for the patient hearted. Back in 1977 the Omaha Astronomical Society received a donated Tasco 20TE from a local MD physician. I was given the ‘scope to store in my townhouse garage for two years. At the time I was building my 6″ f/8 Jaegers and had no interest in this old “relic”. In 1979 the club attempted to sell the scope but one of the club patriarchs came forward and purchased it for $500. He then donated it back to the club around 1993. The club then put it away in storage after several outings with club members by 1995 or so. Things become sketchy owing to membership turnover and lack of records and the like. But basically the club had no use for it. Then in 2008, the 92 year old patriarch and his second wife died. The club then decided to put it up for sale again. I had re-joined the club in 2007 after leaving for personal reasons in 1982. The few members that had seen the scope weren’t real positive of its pedigree and I put two and two together and thought this must be the same scope. Sure enough it was and they agreed to sell the instrument to me for $125.
Some people can appreciate the labor of love that must go into a total restoration of a telescope like this. Others can simply be enlightened. This newly acquired telescope of mine was a nightmare. This was the result of 12-15 years of complete neglect. Membership changes in my local club and lack of records caused some problems with an accurate timeline of events.
Anecdotal evidence suggests that this ‘scope was locked away in an inoperable ROR observatory since 1993 at our club’s rural observing site. Here follows some but not all pictures that I’ve documented.
Optically this scope is in a league of its own. It literally is a step above my Sans & Streiffe 76mm x 1200mm. I was viewing Castor the other night. You could definitely see the different subtle hues….and talk about diffraction rings….and this was at 400x!! The Moon was near the Zenith at half phase and I could not detect any purple in the crater shadows at 400x! Now you can say bull but I couldn’t detect any. At the limb of the Moon you could just detect that something just wasn’t quite correct about this “reflector” like image. I was simply blown away with this lens. Then I go over to the 8-inch and the stars are softer due to the seeing which had a slow boil and a much brighter view of course. The lenses have not been touched. Some dust on back and front sides but no sleeks or scratches or coating flaws.
Thank God they received little active duty and were well capped. After a lot of extensive cleaning; the telescope was proudly displayed on its equatorial mount, where it now enjoys a new life under the stars.
A Short Tribute to Alvan Clark & Sons
By John B, Mid Hudson Valley, New York State, USA
I am a great admirer of old school refractors. The 5-inch equatorial Clark I had in my possession for a number of years way back when gave absolutely exquisite images for its aperture. In fact, over the years I’ve had the opportunity to view through quite a number of the pre-Lundin era Clarks and each produced images that exceeded those found in modern-era telescopes, refractor or reflector. The very finest was the 12-inch in the possession of the late Leslie Peltier of Delphos, Ohio. With it I can only liken what one saw of Jupiter to images rendered by Hubble or modern spacecraft orbiting that planet. The view was so tack-sharp and with detail far beyond anyone’s possible abilities to draw that for the one and only time in my long observing career I got the impression I could literally reach out and touch the planet, as if it were a globe hanging right at the upper end of the telescope’s tube.
Leslie Peltier’s wonderous 12-inch 15′ 7″ focal length Clark I had the opportunity to use several times came as a gift from Miami University of Ohio in 1959. A vintage 1868 instrument, its objective lens was supposedly figured by Alvan Clark senior himself. When originally finished and just before delivery to Wesleyan University (its first home) it was tested by Professor Winlock of Harvard Observatory in Cambridge, Massachusetts, who declared that it “performed admirably.” Leslie, himself, offered that with the Clark “star clusters like M13 are gorgeous quite beyond belief, together with the Ring Nebula and the faint and difficult hot blue star in the center of the ring.
It is right and proper to endeavor to preserve these instruments for future generations.
My Zeiss AS80/1200
By Alexander Kupco, Ricany, Czech Republic
Zeiss AS lenses are one of the legendary objectives made by the company. Having been designed by Dr. August Sonnenfeld in the first half of 1920’s, these popular lenses were in production until the 1990’s when Zeiss closed its astronomical division. At the speed of f/15, they were meant to replace the longish type A Zeiss apochromats. The AS doublets were based on the short Flint glass KzFS combined in Steinheil configuration with regular crown BK7. The resulting color correction was about 50% better than for the doublets made out of standard flint and crown glasses. In particular, the AS80/1200 lens was classified by Zeiss as semi-apochromatic.
Many of my own countrymen who held a longstanding interest in astronomy had telescopes equipped with AS lenses, as Jena were the only available professional opticians available during communist era. Many people have in their homes small Zeiss lenses, mostly achromats – the C50 and C63 in particular – eyepieces, and other accessories. Zeiss refractors were the first proper astronomical telescopes that I have looked through as a kid. When I came across a AS80/1200 lens it was the perfect catalyst to trace a memory line to my youth. So I bought one.
My Zeiss AS80/1200 lens, Fig. 1, came with a price tag people usually pay for one CZJ 0.965″ orthoscopic eyepiece and it also came with two such eyepieces and a Zeiss revolver head.
While for many, the AS80 represents a luxury item, it is for me the cheapest telescope
that I own. The lens came with simple tube. I equipped it with Zeiss helical focuser, new
baffles, and the telescope was ready to go, Fig. 2.
I’m using AS80/1200 regularly for more than three years. It became my primary choice
for winter backyard sessions thanks to its ability to cope with large temperature changes.
I keep the lens detached from the tube at home at room temperature. I just put it out on window-sill before going out. In those ten minutes taken by the preparation for the observation, dressing, and mounting the tube, the lens is ready even for critical planetary
observation at high magnifications. In twenty minutes, I can be done with the sketching
Jupiter including seeing the Red Spot Junior. This is not so trivial accomplishment. My former 130mm ED doublet was just starting to show Great Red Spot under similar conditions after about 30 minutes of being outside. I never had a productive winter Jupiter
session with the large doublet due to the notoriously unstable winter weather. Here is a typical deep sky winter session that documents why I treasure the lens. It was the first opportunity to see stars after 15 cloudy nights. It was clear that the cloudless window is very short. I would not bother to set up my larger 250mm Newton in such conditions.I quickly took out AS80 lens and put the tube on my light alt-az mount. The plan was clear, I wanted to hunt for planetary nebula NGC 1360 in Fornax.
During those cloudy days, I came across an idea to create a list of objects discovered by small telescopes. Planetary nebula NGC1360 was one of the interesting objects I have learnt about thanks to this survey. I have never dared to even look at Fornax area before. From my location, a small town just on the border of 1.5 million people city, I usually cannot see by eye even Eridani. This night was special, the transparency between clouds was excellent and I could easily identify the star by eye.This star was a starting point for the hunt. I jumped from there to a nearby system, o2 Eridani. I remembered from two years ago that it had been a nice triple star with white dwarf and one of the smallest known red dwarf stars. At that time, this was an easy object in my 250mm Newton. In 80mm refractor, it was more tricky and it took me some time and untrivial effort to see the third component. A 80mm lens can show isolated 11th magnitude stars without much difficulty, however this red dwarf is placed only 9″ from the 9.5 magnitude white dwarf. No sign of the third component was seen at 171x. There was something at 235x but I had to crank the power up to ridiculous 465x to clearly reveal the presence of the red dwarf. Next object on the way down to Fornax was planetary nebula NGC 1535. I visited it for the first time, and it was a fine view even in small refractor. I could glimpse its ring structure at 96x and 120x. There was no more time to study it at higher magnifications. It was obvious that the clouds are back very soon.
With next jump, I went directly to NGC 1360. The clouds were already there as the number of visible stars in the eyepiece was changing in time. In moments of good clarity, the nebula started to show itself. At 48x with UHC filter, it was very faint milky cloud elongated in north-south direction. I estimated its size from 8′ to 10′. Then, I checked nearby galaxy NGC 1398 which was also discovered in a small telescope. There was no chance however owing to light pollution as UHC filters are not helping on galaxies too much.
Finally, I quickly turned the scope towards another gap in clouds to open cluster NGC 1662. I had run on it two months ago and I liked it. This evening, I could see the cluster already in the 50mm finder as a hazy star. In AS80, it was very fine group of about 8 brighter stars forming ship with short mast sailing roughly in north-west direction. In between the bright stars, I could glimpse with averted vision another dozen of faint companions.
Fifty minutes ran by quite quickly and the clouds were back. I hope the story documents
why I like my small refractors. They allow me to enjoy even the shortest periods of clear
sky in times when I would not be even thinking of taking out my heavy and long 250mm
Another joy with AS80/1200 comes from observing planets and Moon. The superb optics provides breath-taking views. My feeling is that I’m not able to record properly all I can see even on such small target as is Jupiter, so why to bother with setting up something larger. To get a flavour of what this lens is able to deliver, see my sketches in Figs. 3 and 4.
Of course, f/15 refractor is very suitable tool for splitting tough pairs of stars. Zeiss
AS80/1200 is no exception. Small diameter combined with excellent optics provides text-
book in-focus star images, nice Airy disc surrounded by faint first diffraction ring, quite often. There is no need to wait for nights with exceptional seeing.The lens nicely splits stars above Dawes limit. Due to steady Airy discs I can sometimes glimpse even closer companions. It is fun to notice bumps or smaller discs burried partially in the main disc. Some of the most tough doubles that I was able to detect in AS80 were 2780 (6.1+6.8, 1.0″), tight central pair of Sco (4.4+5.3, 1.3″), or Aql (6.3+6.9, 1.4″).
Thanks to the good optics, tight unequal pairs are no problem for the lens. One of the most extreme example is highly unequal pair Dra (2.8+8.2, 4.8″). It took me five attempts made during one year until I run on favourable conditions and I was able to glimpse the faint companion finally.
With time, I was hooked by the AS80 lens more and more. It made me to want trying
other Zeiss optics. I was lucky enough to find several pieces for very reasonable prices.
Right now, I have another AS80/1200 lens from the WWII era, Fig. 5. The glass is held
in a nice brass cell and the lenses are not coated. My feeling is that the older lens exhibits
even better optics that the lens from GDR time. My main telescope, and my pride, that is mounted in my darker-site observatory, is equipped with lens AS110/1650. When I was buying this lens in beautiful brass cell, I had no idea about its connection to the history of Zeiss AS lenses. The surprise came when the lens was dated by Wolfgang Busch, optician and renowned collector of old Zeiss optics.
His estimate, the latter part of 1924, was quite a bit earlier than the year 1926 mentioned in the books for the creation of AS lenses (R. Riekher, Fernrohre und Ihre Meister ). Wolfgang told me that the first AS lenses were made already in 1923 and that my lens is probably the first AS lens made in this diameter. This little touch of history adds a whole new dimension to my observing pleasure.
There are many ways how to enjoy the wonders of the starry heavens. For me, small refractors, like Zeiss AS80/1200, represent a way to enjoy them even under less than perfect conditions or when I’m simply too tired to grapple with something bigger.
A Grandfather’s Promise
By Dimitrios Barounis
You can read Dimitrios’ story here.