Archive for February, 2012

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SkyWatcher 90mm Mak unboxing

February 29, 2012

The Sky Watcher 90 mm Backpacker telescope that I ordered last week was delivered today. I wasn’t sure what all to expect in the box–the list of included items on Amazon is maddeningly unformatted and cuts off midstream. I thought I’d do a series of unboxing photos to document what’s in there for anyone who is considering buying this scope while it’s on sale.

Inside the usual plain-Jane shipping box is the actual product box with pretty pictures.

Inside that box are a backpack, the mount base, the warranty, and–yep–another box, all in their own plastic bags.

I was expecting to find the mount inside the backpack and the telescope inside the box, but I was wrong. The backpack contained the telescope tube–still swaddled in packing material in this shot–and the smaller boxes containing the accessories.

As with all the scopes I’ve bought new recently, the tube was wrapped in tissue paper to protect the finish, then cocooned in bubble wrap, then put in a plastic bag. Note the enclosed silica gel pack and “don’t blind yourself” warning tag.

Accessories, left to right: 90-degree prism diagonal (I was hoping for a mirror diagonal), 8×20 optical finder, and eyepieces. The eyepieces are 25mm, 12.5mm, and 6.3mm Plossls, all with silver barrels and stamped “Multi-coated”.

The back end of the scope, showing off the finish–which is insanely gorgeous–and the little descriptive plate with the scope’s specs. Note that the meniscus corrector plate up front is coated, not multi-coated or fully multi-coated (these are classes of anti-reflection coatings that improve light transfer through the scope; fully multi-coated is best).

Inside the smallest of the nested boxes: the mount, an L-bar adapter, the controller and cables. The L-bar was a nice surprise. Pictures of the assembled scope show the scope mating directly with the mount via its dovetail bar. The L-bar allows one to mount the scope upright instead of on its side, or to mount other devices with 1/4-20 mounting bolts, like cameras, binocular mounts, and other sport optics. Some thought went into the other accessories, too: there are a couple strips of sticky-backed Velcro so you can hang the hand controller on the side arm of the mount.

Everything set up, with an ink pen and the spare eyepieces (1.25″ barrel diameter) for scale. Note the leveling bubble on the mount. I was pleasantly surprised by the tabletop base. It looks plastic-y in pictures but it’s a nice big piece of aluminum with big rubber feet at the corners and a knurled hand-knob underneath for turning the 3/8″ bolt that goes into the bottom of the mount itself. That means the mount can go on any platform with a 3/8″ bolt, which includes most of the better photographic and surveyors’ tripods.

I had little time this afternoon and didn’t want to mess around with putting batteries in the mount and learning how to use it, so I put the scope on the Manfrotto CXPRO4 I use for museum photography and birding. This hall-of-mirrors shot is a typical view down the guts of a Mak. Incoming light passes through the meniscus corrector plate up front, bounces off the primary mirror at the back of the tube, then off the secondary mirror–not a separate piece of glass but an aluminized spot on the back of the corrector–then through a hole in the center of the primary mirror, then either straight into the eyepiece or, more commonly, off a mirror or through a prism that bends the light path by 45 to 90 degrees so you can look down to observe instead of crouching behind the tube to peer through it. The white dot farthest in is my ceiling light coming down through the translucent dust cover on the vertically-facing eyepiece. If you got lost among all of those reflections, no worries–see the ray-tracing diagram for a Gregory Maksutov here.

Outside, ready to go. Note the purplish color of the meniscus, caused by the magnesium flouride anti-reflection coatings. On refractors, the best fully multi-coated lenses look like dark-green holes, they just swallow incoming light like you wouldn’t believe. From what I’ve seen and read, catadioptric scopes like Maks tend to have correctors that are almost invisible if they have top-of-the-line coatings. This less well coated corrector shows some reflections, but in truth the difference is slight, just a few percent of the total incoming light. To see some photos of the correctors on other 90mm Maks, including a Questar, see Ed Ting’s 3-way comparo here.

I was all set up to take some pictures of the male hummingbird who sits in the top of our neighbor’s tree, but the little sod must be psychic. Every time I got the camera settings right and the camera to the eyepiece, he’d fly away. My time was limited and eventually I had to give up and go do other things. You can see some birding photos I got through my old Orion 90mm Mak, including what might be the same hummingbird, here.

I knew from the online UPS package tracker that the scope was coming today. For the past week, Weather Underground was predicting clear skies tonight. But sure enough, the New Scope Curse struck, and about sunset the sky went from a few scattered clouds to completely socked in. So the only views I got through the scope today were of a distant treetop to get the finder aligned, and a few seconds’ observation of that rotten hummingbird. Everything looked good and I didn’t see any obvious problems, but starlight will be the real test, as it is for any scope. Not tonight, unfortunately!

In lieu of a first-light report, here’s what I learned from the unboxing and my few minutes outside with the scope:

HOTS:

  • The scope is real purty. Fit and finish are very nice.
  • Mechanics seem good. Focusing is smooth with no detectable backlash, at least at the low magnifications I was using during the day. Stay tuned.
  • Given my extremely limited time out with the scope, the optics seem fine. At 50x with the 25mm Plossl, I was counting scales on a tiny pollen cone in the top of a tall pine tree half a block away. I had no problem focusing directly to a crisp image, without having to flop around on either side of focus until I got it right–again, under the forgiving, low-mag conditions I was using it in today. No false color detected, but I haven’t really put it to the test yet.
  • I haven’t used the supplied mount yet, but it gives a reassuring impression of solidity and has some nice touches I didn’t expect, like the built-in bubble level, included L-bar adapter, and Velcro strips for hanging the hand controller from the side arm.

NOTS:

  • I’m disappointed that the diagonal has a prism rather than a mirror. Mirrors tend to be much sharper, especially at the high magnifications Maks are capable of delivering. Now, most Mak spotting scopes come with 45-degree prism diagonals so this one isn’t behind the curve, it just seems weird that essentially all Mak-makers (Questar excepted, obviously) hobble their scopes as shipped with inferior diagonals.
  • I knew this coming in, but the supplied finder is tiny, and uncomfortable to use since I have to crouch behind it. Unfortunately I don’t have the 6×30 RACI anymore that I used to use with my little Maks. For review purposes I will use the supplied finder, but when it’s just me using the scope for pleasure I am either going to have to move the 9×50 over from one of my bigger scopes or buy another optical finderscope (or, just maybe, see if I can get along with dead-reckoning using a spare red-dot finder I have laying around). Also, the finder bracket is not one of the convenient two-bolts-and-a-spring models but an old-fashioned six-screw job, which means that getting the finder aligned takes about 5 times as long as I’m used to.
  • The choice of eyepieces is odd, because each one is a factor of two away from another one. One of the most common astronomical accessories is a 2x Barlow lens, which effectively halves the focal length of any eyepiece. Eyepieces are often sold in staggered pairs to take advantage of this. For example, my first scope came with 25mm and 10mm Plossls, which when Barlowed gave me four focal lengths to choose from: 25mm, 12.5mm, 10mm, and 5mm. If they were similarly staggered, the three eyepieces included with this scope could have yielded six magnifications when Barlowed. Instead, they give just four: 25mm, 12.5mm (both natively and with the 25mm Barlowed), 6.3mm (both natively and with the 12.5mm Barlowed), and 3.2mm. So the 12.5mm eyepiece is superfluous if you have a Barlow. On the other hand, this bundle is clearly aiming for everything-a-beginner-needs-in-one-box completeness, and if you don’t have a Barlow yet, having three eyepieces is very convenient. Most other Maks come with just one (although some C90 packages come with two); advantage SkyWatcher.
  • The optics are coated rather than multi-coated or fully multi-coated. I haven’t had a chance to see if this makes a detectable difference at the eyepiece. It only strikes me as odd because I have seen so many affordable Chinese-made scopes that are multi-coated that I had started to assume that was the new baseline.

I see that I went on at much greater length about the nots than the hots. Don’t read too much into that, it’s mostly whinging about accessories which are just as good as or better than those shipped with most other 90mm Maks. The only criticism that applies to the scope itself has to do with a level of lens coating that may not make much difference in actual practice. Remember that these are all first impressions; I have not yet had the scope out under the stars. Until I have done that and reported back, take this post for what it is: a list of parts.

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Two new Astronomical League observing clubs

February 27, 2012

Award pin for the Binocular Double Star Club, from the AL website

My copy of the Reflector, the Astronomical League’s quarterly magazine, arrived in the mail today, with announcements of two new observing clubs: the Binocular Double Star Club and the Analemma Club.

This is exciting news for me. I’m always looking for new lists of things to look at, especially from home. My Herschel 400 project is chugging along, slowly, as I get dark-sky time, but I can’t get to dark sites all the time and I’m committed to observing from home. I really need structured observing lists or else I spend my driveway observing sessions checking out a handful of old favorites and then wondering what else to wonder at. Binocular lists are good because binocular objects tend to be bright enough that I can see them from Claremont with my 15x70s, and double stars are good because they punch through the light pollution pretty well and many of them are strikingly beautiful. I’ve already finished three binocular observing programs (Binocular Messier, Deep Sky Binocular, and Southern Sky Binocular), and I’m a bit over halfway through the observations for the AL Double Star Club and loving it. So a new club that combines binocular observing and double stars is right up my alley. Update Aug 1 2012: As I often do for AL observing programs I intend to pursue, I made up a blank logbook for the bino double star club. It’s free if you want to use it–you can find a link to the PDF on this page.

Award pin for the Analemma Club, from the AL website

The Analemma Club is a little different. You don’t observe a long list of objects, just one over and over: the sun as it traces out its figure-eight path, or analemma, in the sky over the course of a year. That path is created by Earth’s axial tilt and its elliptical orbit around the sun. A Google Image search for ‘analemma’ will show many composite photos created by amateurs that show the position of the sun in the sky at regular intervals over the course of a year. An analemma can also be recorded by projecting the shadow of a gnomon on the ground, a wall, or a globe–the Wikipedia article on analemmatic sundials has a couple of examples, and there are loads of instructions on how to build these things scattered around the web. Once you have a complete analemma, you can do all kinds of things with it:

  • Calculate your observing latitude and the tilt of the Earth’s axis
  • Sketch or plot the path of the sun on the celestial sphere
  • Calculate the Equation of Time
  • Calculate the eccentricity of the Earth’s orbit

All of this requires math–alegbra and trigonometry. And in the Analemma Club, you have to first generate an analemma and then do that math; the list of four things to be calculated and sketched is taken from the Analemma Club page. Now, I realize that following the sun for a year so you can do math is not everyone’s idea of a good time. But I’ve always been fascinated by sky motions and I’m sufficiently interested in analemmatic sundials to have started a project folder for one at some point, so this club may be the kick in the pants I need to actually, you know, do the work.

So, that’s why I care about these new clubs. Why should you care? Well, if you’re in the US and you’re a member of an astronomy club, you’re almost certainly an AL member already, so if you’re doing any regular observing programs you might as well send in your observations and get some bling.

What if you’re not a member of an astronomy club, or not in the US? Well, if you find the observing programs useful, do ’em anyway. All of the requirements are freely available online, and although the bling is a fun perk, the real benefit is in learning your way around the sky, developing your observing skills, and most importantly, seeing a bunch of awesome stuff.

As of this writing, the Astronomical League has 34 different observing programs (and 3 clubs that have no observing requirements), covering everything from Earth orbiting satellites to distant galaxy clusters. Several clubs require only naked-eye observations, several more require binoculars, and the vast majority can be completed with an inexpensive telescope. So whatever your available gear or level of experience, there is probably an AL observing program that would suit you. Go check ’em out.

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The moon, Venus, and Jupiter, as promised

February 26, 2012

A followup from a recent post. Here’s how the celestial trio looked from my driveway last night. Venus is lowest and Jupiter is highest. No scope for this shot, just my old Nikon Coolpix 4500 on a tripod, about a 1 second exposure. The CCD is a little noisy at that length, especially in low light, so the picture is more pixellated than I’d like, but it’ll do.

Here’s a closeup of Venus and the moon, shot through my SV-50 and a 32mm Plossl (7x), unzoomed.

Tonight the moon is up by Jupiter, and even closer to the King of Planets than it was to Venus last night. I got a quick naked-eye look as we were off to dinner tonight, but by the time we were done eating, the clouds had rolled in, the moon was just a bright fuzzy spot in the sky, and the planets were completely obscured. So it goes.

Next month Venus will be even higher in the sky and Jupiter will be a little lower, so the two will be even closer and prettier when the moon visits them next. Even when the moon is elsewhere, the two planets reward study with the naked eye, binoculars, and telescopes. Mars is up in the east right after sunset, as close to Earth as it will get for the next couple of years, and Saturn is rising around midnight for the night-owls. It’s a good time to observe the planets. Even if all you have time for is a naked-eye peek, you can still appreciate that these moving lights in the sky–“planet” is Greek for “wanderer”–are worlds, that we know something about them, and that someday–maybe–we’ll go out there and explore them ourselves.

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Yet another target of opportunity: Deep Sky Companions: Hidden Treasures by Stephen James O’Meara

February 26, 2012

I do have bigger ambitions for this blog than just collecting deals on astronomy gear from around the web, but this one might not be around for long, so here goes.

The short version, if you’re in a hurry: Stephen James O’Meara’s Hidden Treasures, the third volume in his Deep Sky Companions series from Cambridge, usually $46, is currently on closeout for $18.40 at Amazon. As of this writing, there are only seven copies left at the reduced price.

The long version: Stephen James O’Meara is probably the most respected visual observer of astronomical phenomena of anyone alive. His achievements are legendary. As a teenager, he saw and sketched spokes in the rings of Saturn. Professional astronomers dismissed the spokes as an optical illusion, because the differing rotation speeds of the rings would disrupt and smear out any radial linear features. Then the Voyager probes got to Saturn and, lo and behold, the rings did have spokes–probably electrostatically charged dust floating above the rings and rotating at the same speed as the planet. For most of us the planet Uranus is a dim blue-green dot if we manage to track it down at all; O’Meara saw white clouds on Uranus and mapped their progress to make the first-ever determination of the planet’s rotational period, which was unknown at the time as no space probes had yet made it to Uranus. Voyager II later confirmed O’Meara’s estimate. The list goes on–there’s a pretty good mini-biography of O’Meara in Timothy Ferris’s Seeing in the Dark that describes more of his exploits and achievements.

O’Meara might just have the best vision of anyone alive–at least, when his vision has been tested, it has been sharper and more sensitive than that of any other person who has ever been tested. These tests, by the way, have included having O’Meara sketch faint stars and then comparing his sketches to long-exposure photographs taken with giant telescopes; frequently O’Meara has been able to see things at the eyepiece that no one else can confirm, even when he tells them exactly where to look. (That must be frustrating!)

By all accounts, O’Meara is not only a tremendously accomplished observer but also a darned nice guy. In addition to the Deep Sky Companions series and his other books, he has written observing columns for both Sky & Telescope and Astronomy (and probably others I don’t know about), and his writing is always full of wonder at the night sky and encouragement for his readers to get out and see these things for themselves. One might expect the world’s best visual observer to put on airs and tell the rest of us lesser mortals what deep sky objects really look like. But O’Meara takes the opposite course. He always emphasizes that visual observation of the night sky is an intensely personal experience, presents his impressions of deep sky objects as just that, his impressions, and encourages his readers to get outside, see for themselves, and form their own impressions.

The Deep Sky Companions series now includes four books: The Messier Objects (1998, 318 pages), The Caldwell Objects (2003, 500 pages), Hidden Treasures (2007, 602 pages), and The Secret Deep (2011, 498 pages). The Messier and Caldwell volumes cover the 109 objects on each of those lists in detail. The newer volumes also cover 109 deep sky objects apiece, in homage to the Messier and Caldwell lists, but don’t represent formal observing lists. Instead, the objects are chosen by O’Meara to help observers find and explore some of the lesser-known gems of the night sky.

I haven’t yet seen The Secret Deep, but of the first three volumes, each is better than the last. The Messier Objects introduces the basic format for the series: each of the 109 objects in the book is the subject a multi-page essay that includes its observational history, mythological history (if any), current astrophysical understanding, and visual telescopic appearance, plus a black-and-white astrophoto and an eyepiece sketch by O’Meara. I can’t remember if this is true of the Messier volume–I don’t own it but have only borrowed it from the public library–but the later volumes all have star maps that show the location of each object. The Calwell Objects follows the same format, but the essay for each object is longer and more complete and there is a nice series of appendices, including 20 additional objects readers are suggested to track down and a mini-biography of William Herschel. The Messier volume is a fine book on its own terms, but seems almost skimpy in comparison to its longer sequels.

Hidden Treasures is better still. The star charts are larger and more detailed, the essays are longer and more absorbing, and there is more reference material at the back, including a multi-page table that shows the overlap between the objects included in the book and those on several popular deep sky observing lists, like the Saguaro Astronomy Club’s 110 Best of the NGC.  The mini-biography at the back is of Caroline Herschel, whose formidable achievements in astronomy have been overshadowed by those of her brother William and nephew John. Once again there is a list of 20 bonus objects for readers who want to go beyond the 109 objects covered in detail. The book is a beast, 600 pages long and about 4 pounds. The paper is glossy and the reproduction of the photos, drawings, and maps is very good.

One point of particular interest is an introductory essay in which O’Meara explains how he chose the 109 objects to cover in the book. There were three main sources: O’Meara’s own list of personal favorites, objects combed from several popular “best of” observing lists, and–most interestingly to me–historical lists from the 1700s. There weren’t that many deep sky objects known before William Herschel started his all-sky survey in 1782, and all of them are relatively bright and easy to see in small scopes (otherwise they would not have been discovered in the scopes available at the time), so O’Meara included all of them that aren’t on the Messier and Caldwell lists in Hidden Treasures. Therefore, if you have those three books, you have eyepiece descriptions, up-to-date astrophysical data, charts, sketches, and photos for every deep sky object in the northern skies (i.e., above -10 degrees) known before 1782. That’s pretty cool.

One more point of continuity among the books: O’Meara used a 4-inch refractor from the slopes of Kilauea in Hawaii to observe, sketch, and describe the visual appearance of all of the objects in at least the first three books (except for a few Caldwell objects in the deep southern skies). So observations and sketches among books are directly comparable, having been generated by the same person using the same scope under the same conditions.

I find it interesting and encouraging that O’Meara chose a small telescope to make his observations. Now, O’Meara has the best eyesight of anyone ever tested; his scope, a TeleVue Genesis, is one of the finest refractors ever made; and Kilauea has some of the darkest skies left on Earth. Nevertheless, there are hard physical limits to what a 4-inch telescope can show. O’Meara is humble and forthright in reporting his observations, and when he couldn’t see something–a dark lane in a galaxy, known gas filaments in a planetary nebula–he says so. Anyway, if objects are visible and detailed in O’Meara’s Genesis from Kilauea, they should be observable in commonly available 6- to 10-inch scopes in the more average viewing conditions experienced by most amateur astronomers. So the books are not reports of observations impossible for average stargazers, but guidebooks to help average stargazers make exceptional observations.

I’m happy to recommend all of the books in the Deep Sky Companions series (although I haven’t seen The Secret Deep yet, given the quality of the others I’m prepared to recommend it on faith). If you’re interested in the books, getting Hidden Treasures for less than twenty bucks is an opportunity to test the waters without stressing your wallet. It’s an engaging read on a cloudy night, an enlightening look at how scientific and popular knowledge of celestial objects has changed over the last three centuries, and a genuinely useful guide to finding and observing a host of bright deep sky objects beyond the Messier and Caldwell lists. I ordered a copy when I saw the discounted price, and I’m very, very happy to have it.

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Don’t miss the moon and planets at sunset this weekend

February 25, 2012

From bottom to top: the moon, Venus, and Jupiter, on Feb. 24, 2012.

Venus and Jupiter are both high in the evening sky at sunset right now. Just look west right when it gets dark and they’ll be the two brightest stars in the west. Venus is the brighter and lower of the two.

For the next couple of nights they’ll be joined by the waxing crescent moon. Tonight the moon was just below Venus, so the three bodies were stacked up the sky from lowest and brightest to highest and dimmest.

Early next week the moon will pull away from the planets as it continues on its monthly eastward trek around the sky, but Venus and Jupiter will still be there and looking good.

A close-up of the moon at the same time as the photo at top.

Venus is slightly gibbous right now (between 4 and 5 in the diagram below). On March 26 it will achieve its greatest eastern elongation from the sun, 46 degrees, meaning that at sunset it will be halfway between the horizon and the zenith. At that point it will be half-lit as seen from Earth (5). From then on into April and May, Venus will get lower and larger as it goes into its crescent phase (6) and gets ready to pass between the Sun and the Earth. Venus makes that passage all the time as it transitions from being the evening star (east of the sun as seen from Earth = above the western horizon at sunset, 6 in the diagram) to the morning star (west of the sun as seen from Earth = above the eastern horizon at sunrise, 1 in the diagram).

Phases of Venus as seen from Earth

Because the orbits of Earth and Venus are not precisely in the same plane, Venus does not usually pass directly between the sun and the Earth but passes above or below the sun as seen from Earth. This time will be different; as happens only a couple of times per century at most, the orbits are lined up just so and Venus will pass across the face of the sun as seen from Earth. That’s the transit of Venus I’ve been so het up about. Stay tuned for more on that, and keep looking up at sunset for the next few weeks to see Jupiter and Venus continue their tango.

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More crazy scope deals at Amazon

February 23, 2012

I honestly can’t figure out why I haven’t blogged about this sooner. As happens from time to time, right now there are some screaming deals on scopes at Amazon. The two best are 90mm Maksutov-Cassegrains, a rugged, portable design that has been popular for decades.

The first is the Celestron C90. This scope has been around under the same name since the 1970s, but with three different designs. The first incarnation was a short, all-metal job sold in orange or black livery–you can see the orange-tube version I used to own on the left-hand tripod in this photo–that you focused by rotating the barrel, like a camera lens. The second incarnation was a longer, rubber-armored version more obviously intended to be used as a spotting scope, still with the rotating-barrel focusing mechanism. That one seems to have been discontinued just a few years ago in favor of the current version, which is a very attractive near-clone of the 90mm Synta Maks sold by Orion and SkyWatcher, with a more typical focusing knob at the back. There are differences among the models but they are mostly cosmetic, and the optics for all three brands are made by Synta.

This latest version is the one currently on sale at Amazon. I’ve been watching it for a while and prices have been all over the map, from a low around $140 to a high around $200. For reference, Orion’s StarMax 90 TableTop has an undiscounted retail price of $200 ($210 shipped) so for the sake of this post I’ll define a good deal as anything under $200. As of this writing the C90 is going for $172 with free shipping, which is a steal. UPDATE: OPT has this scope for $179.95 with free shipping right now (Feb. 26, 2012), so if Amazon is out or the price has gone up, check OPT. I’ve bought three scopes from OPT and the customer service has been outstanding, so I’m always happy to send them business. I know the scope is also on sale at other places around the web, but so far I haven’t found any deals as good as Amazon and OPT have on this scope–please let me know if you find a better one!

Most importantly, the C90 has gotten very good reviews, both at Ed Ting’s telescope review site and on Cloudy Nights. Some of the photos of Jupiter taken with these scopes are just astonishing–see this and this (NB: I think both of these are not single exposures but stacks of multiple frames, which brings out more detail).

The other crazy good deal right now is the Sky Watcher 90 mm Backpacker, which is the same tube as Orion’s Apex/StarMax 90 on a tabletop tracking mount. The mount can be put on top of a tripod to function as an alt-az head, just like the unmotorized mount on Orion’s StarMax 90 Tabletop, or you can pull the tube off and put it on the mount of your choice.

I haven’t used this mount so I can’t speak for it, but I’ve heard that it’s popular with daytime photographers because it can remember several pre-programmed points and slew to them on command, which helps people make panoramic photos and such. The tube I can speak for, because I used to own the Orion version, and it is a wonderful little machine, solidly built and typically with very good optics. (If you’re wondering why I don’t own that scope anymore, I sold it to buy a vintage orange-tube C90, sold that because the rotating barrel focuser was a pain to use at high magnifications, and since then I’ve been without a small Mak–until now!)

The SkyWatcher package is apparently on closeout. At least here in the States, SkyWatcher has been absorbed by Celestron (both are owned by Synta, who makes the gear) and the SkyWatcher-branded stuff is being phased out (as I predicted a couple of years ago). So this package might not be around for long. Right now it’s $179 plus $20 shipping, so for slightly less than the StarMax 90 Tabletop you get the same tube and a similar tabletop alt-az mount, only motorized and with tracking (not GoTo; the mount won’t find things in the sky for you, but if properly leveled and aligned it will track things once you find them), and 3 eyepieces instead of 2.

There’s one more scope I should mention: the Backpacker 80R has the same tracking mount with a wide-field 80mm refractor instead of a 90mm Mak. It’s a little lighter and a little cheaper at $155 plus $15 shipping. The refractor tube appears to be the same as Orion’s GoScope 80, which has gotten good reviews both on Amazon and at Sky & Telescope. Be aware of the significant design and performance differences between the 80mm refractor, which is specialized for low-power, wide-field views, and the 90mm Mak, which has a narrower field of view but much more capacity for magnification, especially on bright targets like the moon and planets.

Which of these scopes would I choose? Well, I ordered a SkyWatcher 90mm Backpacker earlier today, so there’s your answer. I’ll let you know how it works out. UPDATE: see these subsequent posts for the unboxing, first light, and some additional observations.

What if you read this post after all these deals are gone? Get one of the Orion tabletop scopes–the GoScope 80 (80mm refractor, $110 right now), SkyScanner 100 (100mm reflector, $110 right now), or StarMax 90 TableTop (90mm Mak, $200 right now). They’ve all gotten good reviews, the Mak isn’t that much more expensive than either of the Maks featured above, and the refractor is significantly cheaper (but lacks the tracking mount of the 80R).

One last thing: if you get a C90, don’t just slap it on a cheap photo tripod. It’s too heavy, and at the relatively high magnifications the scope’s long focal length delivers, the shakes will drive you crazy. Trust me, I hated my first Mak until I got a decent mount and tripod for it. You’ll need something like the Orion VersaGo II, Astro-Tech Voyager, Vixen Mini-Porta, or one of the nicer Bogen/Manfrotto units at a minimum, and these can easily set you back as much as the scope did in the first place. If you’ve already got a cheap tripod and two hundred bucks to spend, I’d go with the SkyWatcher unit or the StarMax 90 Tabletop. With their integrated mounts either one might work on top of your existing tripod, which only has to hold the unit up off the ground, and if it didn’t, you could still use it in tabletop mode while you save for a better tripod or whip up a homebrew (like this one).

Thanks to the folks in the Cats & Casses forum at Cloudy Nights for bringing these deals to my attention, and for the astrophoto links used above. The CN thread on these deals is here.

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Possibly my favorite book: Seeing in the Dark, by Timothy Ferris

February 22, 2012

I have a lot of astronomy books. Some are about astronomical phenomena, celestial objects, and other worlds, some are about telescopes and how to use them, and some of them aren’t really books in the traditional sense but observing tools packaged in book form (the Pocket Sky Atlas, for example).

But out of a couple of bookshelves’ worth of astro books, there are two that stand out in particular: Starlight Nights by Leslie Peltier and Seeing in the Dark by Timothy Ferris. These two are personal favorites of mine. I’ve read them both over and over–in fact, I tend to reread them whenever my interest in astronomy goes through one of its periodic flares. The reason I keep coming back to them is that, alone out of all of the astronomy books I’ve ever come across, only these two capture the enchantment of what stargazing feels like.

Starlight Nights is a wonderful book and deserves a post of its own, which I hope to deliver someday. But tonight I want to write about the other book, Seeing in the Dark.

Ferris is a fantastic writer, capable of taking all kinds of complex ideas and relaying them in everyday terms so straightforward you can’t help but follow along and wonder. Coming of Age in the Milky Way is his Pulitzer-nominated magnum opus, a wide-ranging tour of the growth of astronomical science from prehistory to the end of the 20th century. It is a great book, in just about every sense of the word ‘great’, and one reason is that it never bogs down in dry storytelling. Ferris always has an eye out for the quirks, foibles, imaginative leaps, and lucky breaks that characterize science as a very human enterprise. But he also keeps the other eye fixed firmly on the big picture, our place in it, and how harnessing human passion to the cause of science has allowed us to determine those things. The tone of Ferris’s writing is light, which keeps the pages flowing past like water, and generates a calm into which his occasional profound observations fall like thunderbolts. Reading his books makes you glad to be alive; they are best read on rainy days and cloudy nights, because on sunny days and clear evenings they will make you want go outside and experience the universe firsthand.

Coming of Age is anything but stilted, but it is an ambitious work that only avoids the description of ‘scholarly’ because Ferris’s prose goes down so easily. Seeing in the Dark is a more personal book, an informal ramble through the history and present of amateur astronomy and through the author’s personal history as well. Many of the autobiographical passages make me smile with recognition (from page 22 of the paperback):

If you’re young and don’t know where you’re going, the highway is an excellent place to be. The police officers I met along the way would sometimes ask, “What’s the hurry?” but there was no hurry. A dedicated high-speed driver isn’t anxious to get somewhere; he’s already there, where he wants to be–at speed, with the car seemingly shrunk to the size of a motorcycle, or the motorcycle to something not much larger than his hands and wrists, screaming down a road that also has shrunk, to the thickness of one pounding vein, in which somehow there is always just enough room to get by, with nothing in his ears and mind but the scream of the engine and the sound of good strong music, bounced off the “ozone.” Endlessly flying up the road–and for some reason, late at night, two-lane blacktops always seemed to be leading upward–peering into the headlights’ yellow eclipse, I was as alone as some future astronaut adrift in the hard vacuum past Titan. But I never felt lonely. I was in just the right place.

Photo by Thad VSoke, from TWAN

Oh man does that bring back memories, of driving across Oklahoma, Colorado, Utah, Nevada, often at night, with the vast empty spaces of the American West lit only by the light of the moon and stars and the tiny almost hearth-like warmth of the headlights. I was also never bored and never lonely. Despite my being jacketed in a car, in a strange way those long drives were and are opportunities for me to commune with nature, to revel in the existence of places that are so big and old and profoundly unprofitable that even in the 21st century they are largely unmarked by hand of man–a yearning that extends smoothly and naturally into the night sky.

Seeing in the Dark is divided into three big sections. The chapters under the first heading, The Shore, deal with  astronomy, amateur astronomy, and amateur astronomers as things-in-themselves, and also with Ferris’s boyhood forays into astronomy, setting up spindly telescope on the roof of his parents’ Florida house to plumb the heavens and watch the occasional Space Race rocket launch. In Blue Water Ferris takes us on a tour of the solar system, from the sun to the comet belts, with each chapter focusing on one planet or class of object and the strange and often hilarious histories of their scrutiny by astronomers both amateur and professional. The final section, The Depths, takes us to the stars, the Milky Way, other galaxies, and ultimately to the edge and beginning of the universe. But Ferris isn’t done yet: the final 70 or so pages of the book include appendices to get one started in stargazing, notes, and a glossary. It’s a smart setup, and one I’ve never seen replicated anywhere else: by the time you finish the book, you’ll want to go stargaze, and right there Ferris gives you the tools you need to get started.

And, as I said, Seeing in the Dark captures that magical sensation, easy to recognize but almost impossible to describe, of what it is like to observe the night sky. From page 50:

I pressed a button on the steel control box, and the telescope glided toward the center of the nebula. I gasped  at the sight: Reefs of brick-red and pearl-gray gas clouds were parading by…. Their light had been traveling through intergalactic space for 180,000 thousand years, dissipating all the while as it spread out, but it was still bright enough to make me squint. I recoiled, and found myself gazing at a stream of light that spilled out from the eyepiece like a flashlight beam. Looking up, I saw that it projected a fuzzy, circular image of the nebula on the inside of the dome.

The night assistant’s voice crackled through the intercom. “Tim, you OK down there?” I tried to speak, but could find no words.

I could go on like this for days, quoting favorite passages from the book, and I probably will do just that in other posts. But for now I will just leave you with one more, and call it good (from page 64):

Stately, self-possessed, a murk of mingled stars and gas clouds presenting itself to the eye in hues of silver to charcoal to India ink, a galaxy is so commodious as to contain, I should think, more stories than anyone, anywhere, shall ever come to know. Although there was no sign of a supernova in this particular galaxy on this night, I lingered a moment before moving on, just to look. I felt absurdly happy, like the early French balloonist who, once aloft, refused to come down.