Jumat, 15 Januari 2016

Amateur Astronomy the Old Fashioned Way with Shelley and Me


?The best telescope is the one that gets used the most.? ?The older I get, the lazier I get.?  Ain?t both of those things the freaking truth, and especially the latter, muchachos?  As Gaia has rolled around ol? Sol yet another time, I?ve found myself increasingly less likely or willing to set up my 12-inch Dobsonian or even my 8-inch SCT for a quick backyard gander at the Moon?or anything else.

Something else that has increased as the years pass is my nostalgia for the things of my youth?or the things I wish I?d had as a youth. Like those luscious Unitron refractors of yore with their long, gleaming white tubes. You can?t go home again; the stream of time flows on carrying the past out of reach. Sometimes, however, you can unexpectedly get a taste, a whiff of that past. Which happened to me via an unexpected gift.

As you learned here a few weeks back, I received a semi-vintage and somewhat spiffed up Celestron C102 from my old friend Pat Rochford some months ago. Not long after we moved into the New Manse in May. A C102 ain?t a Unitron. But it is at least in the spirit of those icons of refractordom, which your old Uncle, like every other space-smitten little kid dreamed of owning in 1965 but could never afford.

?A Celestron refractor, Unk? I thought Celestron was all about SCTs.? Not at all, Skeezix, not at all. Celestron?s C102 goes all the way back to the early 1980s. In them days, Celestron was selling considerable Vixen gear. That Japanese manufacturer was highly regarded by amateur astronomers of the time, and Celestron had begun selling Vixen?s Super Polaris mount with one of its C8 models. Before long, the company expanded their Vixen offerings to include a couple of that company?s Newtonian reflectors and several refractors including a 4-inch achromat, the C102.

Despite the 1980s being the age of Dobsonians and SCTs, the C102 was highly regarded. While it was an achromat and suffered from excess color?purple halos, that is?on brighter objects, its reasonably long (by today?s standards) focal ratio of f/10 kept that to bearable levels. The only fly buzzin? in the C102 ointment was that the Vixen Super Polaris mount, which was more than sufficient for the C8, was stressed by the long tube of the 4-inch refractor.

It took a while for Celestron to rectify that shortcoming, but rectify it they did in the early 90s when they began selling the C102 on Vixen?s improved medium German equatorial, the Great Polaris, which is the ancestor of all the Chinese ?GP clones? with us today including Celestron?s CG5s and VXes.  The mount, while not overkill, was more than sufficient for the C102.

?And the C102 lived happily ever after, continuing to meet the wants and needs of decades of achromatic refractor fans.? Not exactly. By the mid-90s the bloom was off the Vixen rose for Celestron. Prices for the Japanese maker?s gear were climbing at the same time the Mainland Chinese company Synta was coming on strong. In 1998, Celestron replaced the Vixen Great Polaris, both for the C102 and for its GEM-mounted C8, with the ubiquitous Synta EQ-4, which Celestron dubbed the ?CG5.? They didn?t stop there. Henceforth, Synta would also make the refractor?s tube assembly.

Was this new C102 an improvement? No. It was a cost saving measure, and there was good and bad in the new model (which looked almost identical to the GP-C102). The good was that, almost unbelievably for those of us who?d thus far looked askance at Chinese refractors, the optics in the Synta-made C102 were virtually indistinguishable from those in the Vixen. The OTA itself? The focuser was no great shakes, but it was an OK rack and pinion. The dirty little secret? The Vixen focusers weren?t so hot, either.

The mount was a different story. The early manual CG5s have little to do with the latter day goto CG5 so beloved of cost-conscious amateur astronomers. The wooden tripod was history, replaced with an extruded aluminum job just this side of flimsy. What little smoothness there was in the declination and right ascension axes was attributable to the infamous Chinese glue-grease, which was applied in large dollops. The mount was workable for the new C102, but just barely.

Nevertheless, thanks to its consistent optical quality, the C102 OTA just kept on trucking year after year, hopping on different mounts as time passed and occasionally undergoing minor styling revisions, but staying good, very good. Whether on one of the NexStar goto mounts, or, as today, on Celestron?s non-goto CG4, ?C102? spells ?Celestron? every bit as much as ?C8? does. One nice change to the Chinese C102 a few years after its introduction was that the original 1.25-inch rack and pinion was replaced by a 2-inch job.

Want a C102 today? Celestron?s CG4 ? C102 combo is nicely priced at $499.95?the scope is not over-mounted on the CG4 GEM, but the mount is sufficient for it. What?s truly amazing, however, are the periodic C102 OTA sales you can find, especially from OPT, Oceanside Photo and Telescope in Cally-for-nye-ay. Right now, you can get an OTA for 170 dineros, and last year they were selling the scopes for the astounding price of 50 bucks. At any of the above prices, the C102 is an incredible buy.

Not that your old Uncle necessarily believed that when Pat dropped the C102 off at the New Manse. Oh, I remembered how Mr. Pat had raved about another 102 he?d owned years ago, how it literally tore up the dark night sky at the Chiefland Astronomy Village one cold winter night in 2001 (the year the Winter Star Party was canceled and many WSP refugees wound up at the CAV). Still, I wasn?t quite convinced. An achromat, a 4-inch at f/10?

To get the cursed color purple down low on a 4-inch, you have to go to f/15 or f/16, like those long, long Unitrons. On the other hand, I recalled having had a hell of a lot of fun with my old Short Tube 80, Woodstock (who has since gone to live with Unk?s son, Chris), and that 80mm f/5 certainly wasn?t lacking in chromatic aberration.

The bottom line on excess color? It bothers some people more than others. Me? I am not overly troubled by it, whether it?s around bright stars or turning lunar shadows a deep purple instead of inky black. The question would not be whether it would disturb me, but how much?if any?sharpness it would steal from the C102?s images. That is the real problem with chromatic aberration. At high levels, it blurs the image. Howsomeever, I well remembered one cold night in 1999 when I watched a triple shadow transit on Jupiter with Woodstock. I was amazed at how sharp the planet was. So, I was willing to give the C102 a tryout.

What with all that was involved in getting settled in the New Chaos Manor South, it took some time for me to get around to giving Miss Shelley a tryout. ?Shelley?? I don?t name my telescopes, y?all. Oh, they all have names, but I don?t give them names, they tell me their names, eventually. It took a while but my C102 finally whispered that she is to be called ?Shelley.?

Anyhoo, what prompted me to give Shelley a go was that I had come to favor refractors for my quick backyard observing. I can waltz one out of the sunroom and onto the deck in 15-seconds flat. Not that Shelley didn?t have competition there. My 80mm APO does a fantastic job on everything in that role, and Miss Dorothy?s Explore Scientific AR102 does too, and with a little more aperture. Unk got to thinking, however, that it might be nice to have a little more aperture to play with than with the APO and a little less color than presented by Miss D?s f/6.5 telescope.

The results? You can read all about it at the link above, but for visual, Shelley takes the laurels. But not by much. While the C102 threw up a dadgum impressive star test, the 80mm APO, Veronica, does too, and despite her smaller aperture doesn?t fall far behind in visual performance. If she does at all. There?s more to a scope than just performance, though; there was something about the C102?s long tube towering above me. It was if at least some of those daydreams I dreamed while mooning over the old Unitron catalog as a sprout were finally coming true. Color? There?s purple, but it is bearable.

I did quite a bit of touring of the bright deep sky objects with the C102 on the moonless nights that followed, but there?s only so many times you can look at M2, M13, M92, and the rest of the showpiece gang before getting a mite bored. Oh, the summer and fall Messiers were as beautiful this autumn, my 50th autumn observing them, as they ever were, but no matter how pretty they looked in my ?new? telescope, I wanted some variety in the backyard. What else could I do with Shelley? What would she be good at?

One afternoon I was shelving some books that had come over from the old Chaos Manor South in a box, and ran across a real blast from the past, Herbert Bernhard, Dorothy Bennett, and Hugh Rice?s New Handbook of the Heavens (1954). It was one of my favorites in the hallowed day, not only because of its clear prose and the observing lists at the ends of its chapters, but because it had come in the box with my Palomar Junior. Surely if Edmund Scientificincluded the book with their scopes, it mustbe a dang good one.

The New Handbook is actually a follow-on to the original Handbook of the Heavens (1935), but while it is an update, there is no question it is still about the old amateur astronomy. An amateur astronomy where the deep sky took a decided backseat to other pursuits.

Take a look at the Handbook?s table of contents and you?ll find you have to scan down almost to the bottom to come to the ?Star Clusters and Nebulae? chapter. The authors do do a good job describing what there is to see of the deep sky with a small telescope, and at the end of the chapter, there?s an outstanding list of 60 of the best of the best DSOs for little scopes.  Most of the Handbook?s space is devoted to the things most amateurs of 1950s - 1960s observed more often than even the bright Messiers, however. The emphasis in the book is on the Moon, the planets, and double and variable stars. 

Why did amateur astronomers tend to restrict themselves to those subjects when a mere 4-inch refractor or a 6-inch reflector will do one heck of a job on the deep sky? Because most amateurs, even in the 1960s, didn?t have a 4-inch refractor or a 6-inch reflector, with the refractor being a particularly tough nut to crack for most of us. Edmund Scientific?s reasonably priced 4-inch refractor, for example, was $247.00 (their 6-inch Newtonian was 50 bucks less).  Depending on how you calculate such things, that is equivalent to at least $1370.00 today. A high-toned refractor like a Unitron? Don?t even ask, Bubba, don?t even ask.

Because of the way-out prices for store-bought scopes, amateurs in the 1960s, and not just kids, often made do with 2.4-inch refractors and 3-inch reflectors. Yeah, you?d think from what the old timers down to the club say that everybody back then was grinding and polishing 6-inch mirrors, but that was most assuredly not the case. Then as now, most of us, and especially us sprouts, were amateur telescope buyers, not amateur telescope makers. Accordingly, astronomy authors tended to restrict themselves to objects within range of our small scopes:  double stars, the planets, the Moon, and the brightest deep sky wonders.

Its focus on the bright stuff made the New Handbook of the Heavens, Unk thought, just about the perfect guide to what I would enjoy with my 4-inch lens-scope from my light polluted backyard (limiting magnitude at the zenith not much better than 5 on a good night).  There was also just something romantic about pursuing the old amateur astronomy, the amateur astronomy of Patrick Moore in his heyday, with a long-tubed refractor on chilly (well, for down here) fall nights. I?d already done a quick survey of bright DSOs; it was now double star time.

I?ve never been the world?s most committed double star observer. I?ve blown hot and cold on binaries and multiple stars over the last half century. Obviously, my contributions to and support of The Journal of Double Star Observations are signs that these stars are an important interest of mine; I?m just a-saying you shouldn?t imagine I go pair-hunting every dadgum night. I still and always will love doubles, however, and was happy to have an excuse to look at the best of the best with Shelley.

Before I could do that, howsomeever, I needed to rectify the finder stichy-ation. As Mr. Pat delivered Miss Shelley, she was equipped with a pretty but too small 30mm finder. I immediately replaced that with a red dot job, which, even in our gray skies, was sufficient for locating the brightest Messiers. To run down medium bright doubles, though, much less dimmer ones? Uh-uh. Luckily I had a 50mm Orion RACI finder sitting unloved in my shop. It was in a Synta mount and would slide right onto Shelley.  I am not a huge fan of right angle finders, correct image or no, but I figgered the RACI would at least be superior to the alternatives.

So it was that I began a survey of Double Star Gooduns on a chilly (40s, y?all) November evening. The sky wasn?t perfect; haze was moving in ahead of a front and one look at Vega showed the seeing was at least semi-punk. But I?d been down in the dumps?for no good reason, really?all afternoon and figgered an hour or two under the stars would help, even if conditions weren?t all they ort-ta be. While I used the New Handbook as a general guide to what would be fun look at, I didn?t try to decipher its small text under a red light. Instead, I loaded up the Astronomical League Double Star List on SkyTools 3 on my Toshiba laptop.

One of the loveliest things about a refractor? Just a few minutes acclimating to outdoor temperatures on this cool night and one is ready to rock. I?d mastered the fine art of moving Shelley from the sunroom where she lives out onto the deck without removing her big tube from her SkyWatcher AZ-4 alt-azimuth mount, and in five minutes I was ready to start looking and she was ready for me to start looking?

Beta Cygni, Albireo

?Two tiny points of light?one rich orange, the other a deep blue?placed close together in the telescopic field?such is the appearance of Albireo?the concealed beauties of many similar stellar objects lie unsuspected until discovered in the telescope.? So says the vaunted New Handbook, and I agree?do I ever. I love Albireo, the blue and gold ?Cub Scout Double,? though I don?t look at it often. I mostly just show it off on public outreach nights, taking a quick glance at it to make sure it?s centered and focused.

On this night, I spent a little time with Beta Cygni. At my finding power, 67x, with the 16mm 100-degree AFOV Happy Hand Grenade eyepiece, the view was scrumptious, and not just because of the deep and vibrant colors as described in the Handbook. What made Albireo doubly outstanding was the tiny perfect appearance stars tend to assume in a good refractor. I stared for at least 15-minutes despite being hunched over at the eyepiece?even at full extension, the AZ-4 tripod is not really tall enough for a 4-inch f/10.

Alpha Ursae Minoris, Polaris

As is often the case when I?m chasing double stars, Polaris was one of the first pairs of the evening. It?s a good test of conditions. As usual, it was easy but not that easy. The secondary was visible, but I did have to look for it in the seeing, which was definitely tending to ?poor.? It soon showed itself as a little white spark beside the strongly yellowish primary. Since the separation between the two is 18.4?, you?d think resolving Polaris would be like shooting dadgum fish in a barrel, but it is not so. I could see the comeswith the 16mm eyepiece, but I needed the 7mm to make it really stand out. Polaris is tough because of the difference in magnitudes between its primary and secondary which are, respectively, at magnitudes 2.0 and 9.1.

Epsilon 1 and 2 Lyrae, the Double Double

Since I was in the area, figgered I might as well check in on the famous Double Double, Epsilon 1 and 2 Lyare. Epsilon 1 is at magnitude 4.7 and Epsilon 2 at magnitude 5.1 and they are separated by a huge 208?, hardly a challenge?the split was trivially easy in the 50mm finder. That ain?t the challenge, though, the challenge is that each of these two stars is itself a close double.

Epsilon 1 Lyrae is composed of a magnitude 4.7 primary and magnitude 6.2 secondary separated by 2.6?. Not usually a problem for medium aperture scopes at medium magnifications on nights of good seeing, but more than close enough when, as on this evening, the air doesn?t want to hold still. Epsilon 2 is a magnitude 5.1 and 5.5 pair, and is a wee bit closer together at 2.3?. Again, not a huge challenge, but enough of a challenge when the seeing sucks. What helps is that both pairs? stars are fairly close to each other in magnitude.

Anyhow, despite the relatively lousy atmospheric conditions, Epsilon 1 and Epsilon 2 were split at 143x in Shelley with my 7mm William Optics Uwan eyepiece. I could see that the stars were elongated at 67x, but only barely. Only when the seeing would change and they?d briefly stop shimmering and dancing around.

Gamma 1 Andromedae, Almaak

Almaak is another one of the very best doubles. The ?end? star in Andromeda?s eastern chain of stars is a nice, easy split at 9.0?, which also puts the primary and the companion close enough together that the pair really looks like a double star at medium powers. The primary is a beautiful deep golden color and shines brightly at magnitude 2.0. It is made even more lovely by the contrast provided by the secondary, which stands out well at magnitude 5.0 and has a light blue-green tint.

Despite Almaak being over the house and in the extra poor seeing caused by heat rising from the roof, Shelley did a fine job. At 67X I coulda drove a truck between primary and secondary. Other observations? Mainly that the secondary star looked bluer to me than it does in my SCTs. Whether that is due to the smaller aperture of the refractor, or to the fact that it is a refractor, I don?t know, but the difference was noticeable.

Eta Persei, Miram

Miram is a famous double star, but not one that?s really a showpiece in this old boy?s opinion. The separation, 28.9?, makes it an easy but relatively wide one, and at magnitude 7.9, the secondary star seems somewhat lackluster. The mag 3.8 primary was easy to spot, even in the eastern horizon light dome from consarned Airport Boulevard, and is an obvious deep gold-orange. The secondary? From the first glance, the secondary seemed a pale blue. Not the ?very blue? the Handbook claims, but blue, not white as it?s appeared in my C8.

Since I was in the neighborhood, I bopped over to the west to have a look at the Double Cluster, just a little less than four and a half degrees away. Despite still being in the heavy light pollution and in increasing haze, the two companion open clusters were wondrously beautiful in the Happy Hand Grenade. There is just no way to make ?em look bad, y?all. But, as I watched, they began to do a fade out. The occasional bands of thick haze were morphing into genuine clouds and it was time to throw the Big Switch.

Throwing that Big Switch took all of maybe two minutes. Objective cap on the scope, pick her up, and back into the house we went in nuttin? flat. Grabbed the eyepieces off the patio table and we was done. I didn?t have to pack up the Toshiba, since I?d set up the laptop in the sunroom so I could duck inside and warm my old bones when scoping out the next target star with SkyTools.

Yeah, double stars were great in the refractor, muchachos, but that is hardly all she can do. In addition to a surprisingly good job on the deep sky, she has made a believer out of me when it comes to the Moon, and I originally intended to clue y?all in as to how Luna looked in the achromat. Unfortunately, I see it is time for me and Shelley to run along before we wear out our welcome this Sunday morning. You will hear more about our adventures soon, and not just on the Moon, but on the planets?King Jupe is on his way back into the evening sky, and I am curious what my new friend of a telescope will accomplish there.  

Next Time:  Unk's Astroware Top 10? 




reff : http://uncle-rods.blogspot.com/2014/11/amateur-astronomy-old-fahsioned-way.html


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