Sunday, April 24, 2016
Issue #490: The Refractor Way Part 5: Is One for You?
As you have probably noticed if you are a regular here, over the last year I’ve been revamping my telescope lineup (amongst other things). I don’t just mean I’ve been reducing scope head-count, though I have been doing that. I’ve also been developing a radically different take on telescope aperture and, especially, telescope design.
To recap the past year’s minus column, almost unbelievably my much-loved 1994 12.5-inch Dobsonian, Old Betsy, was sold. Also out the door went three freaking C8s including my 1995 Ultima 8, Celeste, who’d been to more star parties with me than even Betsy, I believe. My old-time classic Criterion RV-6 Newtonian also found a new home. Finally, my C11 may go as well.
The pluses, the newcomers? First there was Zelda, a 10-inch Zhumell Dobsonian. After her came Hermione Granger, a beautiful and bewitching SkyWatcher Pro 120ED APO refractor. Finally, there was Big Ethel, a 6-inch achromat of somewhat uncertain parentage (though there’s likely some JOC in her heritage; she looks an awful lot like the old Meade AR refractors).
What was the why and wherefore of all these changes? In Betsy’s case it was guilt. Guilt that she was sitting in my shop (a.k.a. “The Batcave”) unused week after week and month after month. The ground truth was that even though my friend Pat had done a lot to lighten up the old-style truss tube 12.5-inch telescope, she was still more of a handful than I wanted to handle, even for star parties and other special observing runs.
The C8s? I was holding onto three 8-inch Schmidt Cassegrain OTAs because…well…because I could. Honestly, while I’d had the Ultima 8 OTA, Celeste, out a time or two since I bought my Edge 800 C8 in 2013, it was only a time or two, and the other pair of 8s had not been used at all. Why would I? The Edge 800 (“Mrs. Emma Peel”) is the best C8 I have ever owned or used.
Now for the incoming telescopes. My acquisition of Zelda, a GSO 10-inch Dobbie, is easy enough to explain. I like to have a large—well large for moi—scope in the inventory. 95% of the things I want to see/like to look at are just fine in a 4 – 8-inch instrument. But there’s that remaining 5%, which is comprised of dimmer stuff. And sometimes I also want a little more horsepower on the bright objects, horsepower provided by 10 – 12-inches of aperture, which will make Messiers “spectacular.”
“Well, Rod. You’ve got a C11.” That I do, and I tried to make myself start using Big Bertha more than I have over the last four years. I removed her from her old GPS fork mount and put her on a Celestron CGEM. That did help encourage me to get her out a little more, since I no longer had to lift 66-pounds onto a tripod. But only a little more. The switch to the CGEM just didn’t help enough.
Setting up the 11 and the CGEM is still enough work that I rarely undertake it. Since the end of my observing program of a lifetime, The Herschel 2500 Project, which was mostly undertaken with Bertha, she has, like Betsy, sat unused. I haven’t yet worked up the nerve to sell the carbon fiber C11 OTA, but it’s become evident I am probably not going to use her much anymore.
Enter Zelda. As I mentioned last time, 10-inch Chinese Dobsonians are both affordable and manageable. For 500 bucks delivered, I got not just a scope with surprisingly—maybe even amazingly—good optics, I got a couple of usable eyepieces, a cooling fan, a laser collimator, and more. Best of all, I don’t mind setting Zelda up in the backyard on any but my laziest evenings.
Now the hard part. Has your old uncle gone from being Mr. SCT to Mr. Refractor? Let’s get one thing straight: I’ve actually used refractors for a long time, including a pair of spectacular William Optics APOs, an 80mm fluorite job and a 66mm “SD” (ED) baby. There’s also been a 4-inch f/10 achromat, a 4-inch f/6.5 achromat, an 80mm f/11 achromat, and, the ancestor of all of them, the Short Tube 80 who came to live with me in 1999.
But why do I seem to be emphasizing refractors now? Simple, boys and girls: they are just so easy. My 11-pound 120mm APO, for example, is wonderful on the CGEM when I want to do serious imaging. She is fine on the Celestron VX when I am not quite so serious. And she is usable on my uber-portable SkyWatcher AZ-4 alt-azimuth mounting when I am not serious at all, just wanting a quick peek at Jupiter. The light weight of the scope is just the lagniappe on top of her other refractor advantages, like very little cool-down required and no need to even check collimation.
There is still more to it. Not only are the visual looks I get through the 120 very much on a par with what I see in the Edge 800, they have that almost indefinable refractor je ne sais quoi. Yes, some of that “refractor images are so sharp; their stars are so tiny” business is due to their (usually) shorter focal lengths when compared to SCTs. But, in my opinion, refractor images really are sharper. There’s also more contrast compared to an obstructed scope, and refractors’ thermal characteristics really allow them to capitalize on their advantages.
Even more important to me than the visual advantages offered by a refractor, however, are the imaging characteristics of the lens scopes. That’s a big deal for me now, since I am on an astrophotography jag again—hell, I even have an AstroBin account now. There’s no focus shift or mirror flop to worry about and so no need for add-ons or work-arounds to exorcise those SCT gremlins. There’s also the usual short focal length and wide-field character of APOs to consider. In addition to allowing wider imaging vistas, if that is your bag, the smaller amount of millimeters of the average APO makes guiding mucho easier.
Are the images produced by a refractor better, though? Better than those I can get out of my Edge 800? Optically speaking, probably not that much. Deep sky imaging is pretty forgiving of optics anyway. However, the pictures I can turn out with the 120ED are nevertheless better than the ones I can do with the Edge. That’s because of the inherent ease of focusing and guiding the refractor. A refractor is just a dream for me to use for imaging after coming off 35 years of using SCTs for deep sky work.
So, here is the bottom line: I ain’t that old, but I am well into my spring semester, and I expect the ease of use and portability of the refractors (and the 10-inch Dobsonian) means they are likely the telescopes that will see me into Final Exam Week, if you know what I mean. In the amateur astronomy game never say never, but I simply cannot see myself acquiring larger/more difficult telescopes.
Does this mean I am against SCTs now? No, not at all, not hardly. For many, many of you, especially novices, an SCT is still the best telescope. Can’t help but be. While one is not the best scope at anything, one is good at almost anything. And if you don’t know which area of observing interests you most yet, a Schmidt CAT is definitely the telescope for you. Even if it is not always the best telescope for you, it may be the best telescope for you for a long time. I sure had a good long run with the CATs, 37 freaking years if I date the beginning of my transition to lens scopes to about 2013.
Just because a refractor is the telescope most useful for me doesn’t mean it is the most useful telescope for you, however. Let’s see if one is…
A Refractor May be for you If:
You are interested in wide field viewing and imaging. Sure, you can use an f/6.3 focal reducer on your f/10 SCT to open it up a bit, but you are never going to get the wide open spaces delivered by the average f/6 or f/7 APO. Use an eyepiece longer than about 25mm with your reduced SCT and you’ll get severe vignetting.
Certainly, if, like most of us, you live where light pollution is a factor, you won’t get to exploit this refractor strength often—the sky background will just be too bright at low power—but when you can get out to a dark site, you will be terribly impressed at what a four or five inch f/6 will show.
You are more interested in the aesthetic quality of images than in seeing the dimmest, most difficult details. Only you can decide what is more important to you, the pinpoint stars and high contrast of a five inch refractor or the light gathering power of a 10-inch (or larger) SCT or other reflector. Or you can, like me, have the both of best worlds, and keep a low-cost Dob in reserve for those times when you want “deep” more than “pretty.”
Ease of setup is important. Yes, there comes an aperture point where refractors become difficult. That point doesn’t come until 6-inches, however. A 5-inch can provide most of the horsepower of a 6-inch, however, and can be remarkably easy to mount and awfully forgiving of the mount. And as hefty as she is, I’d still rather set up my 6-inch f/8 refractor than my C11.
You like pretty things. Yes, I think my Edge 800 is a very attractive scope, but, c’mon, there’s just something about a refractor out on an observing field pointed up at the sky in the gloaming that spells a-s-t-r-o-n-o-m-y.
You are into imaging the deep sky and are more focused on medium-size/larger objects than smaller galaxies and planetary nebulae. This is where refractors really pull ahead. As above, they are generally much easier to use for picture taking, particularly by beginners, than an SCT (or a Newtonian). And remember: on extended objects more aperture doesn’t get you “brighter,” it merely gets you “bigger.” The required length of an exposure depends only on the f/ratio of the telescope.
A Refractor May Not be for you If:
You are after the dimmest of the dim objects visually. There’s an old saw you will hear repeated frequently in places where hardcore visual deep sky observers gather: “aperture always wins.” There is no denying that is true. All things being equal (they seldom are), you will see more with a larger aperture scope. Chasing PGC galaxies? You want a 20-inch Dobsonian, not a 5-inch refractor.
You are a planetary imager after the highest resolution images you can get. How do you make high resolution planetary images today? You take thousands of short exposure frames in as short a period as possible. For them to be well exposed, you need plenty of light. The most efficacious way to do that is with a 10 – 14-inch SCT.
You are interested in a turn-key telescope. Something that appeals to beginners who are struggling to keep their heads above water in the murky sea of amateur astronomy gear is the modern SCT. You get a good scope on a fork mount with everything included. There are fewer ready-to-go refractor packages being offered. Usually it is a la carte.
Finally, you may be, as I was for many years, an astro-dilettante. If you want to take pictures of Saturn one night, spectrograms of Rigel the next, and chase the Hershel 2500 the following evening, an SCT could be your scope. In fact, I will say an SCT is your scope.
You know what? There’s actually only one way to decide if a refractor is for you: get out and use one. Join your local club if—horrors—you are not a member, and look through the refractors some of your fellow members are sure to have. Then do some long and hard thinking. If you decide on a lens scope after that, I salute you. Come on in; the water’s fine.
Sunday, April 17, 2016
Issue #489: The Messier Gang 5
What’s a good telescope for the Ms? Almost any will do. You can see all these famous objects with a freaking ETX 60, after all, if you have access to dark enough skies. One good choice, however, one that will reveal plenty of details in all the Messiers under good conditions and not cost much money is the ubiquitous Chinese 10-inch Dobsonian reflector. Not only are these scopes inexpensive, they are relatively portable and from a dark site they are powerful performers.
How good is my Zhumell (GSO) 10-inch Dobsonian,Zelda? Even at a dark site she is not quite as good as my old 12.5-inch truss tube Dob, Old Betsy (sold some months ago), was. There is not a world of difference, no, but there is a difference. Take NGC 4631, the Whale Galaxy, a popular destination this time of year. Compared to the 12.5, the 10 shows a little less detail in the main galaxy, and the companion galaxy, “the calf,” is a mite less prominent. Not like night and day, mind you, but I can see more with a 12-inch.
So, all things being equal, Old Betsy was better than Zelda. All things are rarely equal, however, and that is certainly the case here. Betsy had to be disassembled, the truss tubes detached from the mirror box and the upper cage assembly, for transport. Naturally, she then had to be reassembled at the dark site. And then taken apart when the run was over. Also, while Bets did a fairly good job of holding her collimation following disassembly and reassembly, she would always need to be tweaked.
Finally, as y’all know, I am one lazy mutha these days, and even with all the weight-saving measures my friend Pat applied to Betsy during her last baseline upgrade, her mirror box was still on the heavy side. For me.
Zelda? She’s a solid (steel) tubed scope, so the only disassembly that needs to or can be done is removing tube from rocker. Said tube easily fits into the backseat of my Toyota 4Runner, Ms. Lucille Van Pelt, and the Rocker box goes in the cargo area upright. While the tube is not light, it’s not a problem for even your broken down old Uncle, and all I have to do to get the scope ready to go is place tube in rocker. Oh, and check collimation. While I check it every time, however, it rarely needs even minor tweaking thanks to her solid tube nature. Yes, you could get a solid tube 12.5-inch, but don’t do that unless you fancy wrestling with a water heater, Padawans.
Those are not the only good things about Zelda. While Betsy had a very decent (JMI) Crayford focuser, Zelda’s GSO focuser is better; it’s a two-speed and is smooth and easily handles my heaviest two-inch eyepieces. In a way, it’s not a fair comparison, since I bought the JMI back in 1998, and we’ve come a long way price/performance-wise with focusers, but still…
There’s also Zelda’s fan. She came from GSO with a cooling fan installed on the rear cell. At first I wasn’t sure that was needed, but as below I now believe it can be a help, a big help, in achieving superior images even in my mild climate where indoor and outdoor temperature variations even in winter and early spring are rarely extreme.
So, last Saturday night, which promised to be clear, at least for a while, I was impelled to pack Zelda in the truck and head for our club dark site half an hour to the west of the New Manse, out in the Suburban-Country Transition Zone. While, it did not appear conditions would hold, I thought I’d at least be able to scope out a few Ms, if not any of the subjects for this week, and worse come to worst maybe put in some time with Jupiter, who was now riding high.
Setting up Zelda and checking her collimation (still spot on) was the work of maybe 5-minutes and then it was M-time big-time. First was the bright galaxy pair in Ursa Major, M81 and M82. While the poor seeing and haze didn’t make M81’s arms exactly pop out, it still looked good, as did its companion, M82. Biggest surprise? Even in somewhat punk conditions the less well known third member of the group, magnitude 10.6 NGC 3077 was wonderfully prominent.
Next was good, old M51, the Whirlpool galaxy and its little buddy NGC 5195. This was a test of my somewhat atrophied finding skills, I suppose. Especially since I’d left my tablet, which runs SkySafari 4, at home (by mistake, natch). All I had on me was the smaller sized edition of Sky & Telescope’s Pocket Sky Atlas, which is a little tough for my eyes.
Nevertheless, with the aid of Zelda’s zero-power Rigel Quick Finder and her (included) 50mm right-angle-correct-image finder, I soon found I had nothing to dread. With SkySafari it would have been even easier to get the Whirlpool in the eyepiece, but I must admit that for visual it’s nice to forget about computers and batteries sometimes, even my Asus tablet, a very modest and user friendly computer.
Onward! I guess, like riding a bicycle or copying the Morse code, you never really forget how to star-hop. It took about 15-seconds for me to get on M65, M66, and NGC 6628, the famous Leo Trio. I easily beat a VX mount set up near me to the target. Unfortunately, it was still a bit early and the group was still in the Mobile light dome to some extent. Nevertheless, Zelda easily showed the different shapes of M65 and M66 and revealed the third galaxy (barely).
If I beat the go-to rig to M65/66, I really smoked it on M3. Use the Quick Finder to position the scope in approximately the correct area of Coma, take a look in the finder, which showed the cluster as a fuzz-spot, center that spot in the crosshairs, and I was done. One of the benefits of a 50mm finder is that it will show any decently large Messier from any decently dark site. The cluster? It was down in the light dome, but the power of 10-inches of telescope mirror was apparent; M3 was beautifully resolved in the 13mm Ethos eyepiece.
I looked many objects following M3, but as the night began to grow old the haze began to devolve into real clouds, almost bringing on Big Switch Time. Jupiter was in a sucker hole, though, so I spent some time with him. How did he look? OK, but just OK. The seeing was only enough, just barely good enough, to tantalize with fine details coming and going on the giant planet's disk.
As above, I found the scope’s fan helped. Given the night’s steadily falling temperatures, the fan ensured my higher power images were as good as they could be in the messy seeing. Instead of just running the fan for half an hour before beginning the run, I had it on all night and I believe that is the way to go when the temperature is changing much. The fan, mounted on the mirror cell, will go almost forever on its eight AA cell battery pack and doesn’t introduce any obvious vibration, so there is really no reason not to let it run.
So much for the preliminaries; now for the good stuff. Let’s have a look at this installment’s deep sky treats.
Well, I don’t know if I’d exactly define Messier 28 as a treat, but it is an M, and it is an at least interesting object, if not spectacular. Its basic problem? Not that it’s too small and too faint, not with a size of 13.8’ and a magnitude of 6.9. It’s its declination, almost -25 degrees. That puts it down in the trash for many of us much of the time. The fact that it’s fairly compact, a Shapley-Sawyer Type VII, also doesn’t help when you’re trying to resolve it. It’s not that bad for me down here at 30N, but it is certainly no competition for nearby M22.
One thing you will not have to worry about is locating M28 if you don’t have computerized pointing. M28 is a mere degree northwest of bright Lambda Sagitarii, the teapot’s "lid" star. Once you have the glob in your field, what do you get for your troubles however minimal? This is what I got with Big Bertha, my C11 one fair but not great night at the club site:
Interesting little globular that benefits from higher magnification in the C11. At 200x it wants to resolve. But is still basically a gray, round ball with a few stars winking in and out with averted vision.
Messier 29 is a sparse open cluster in Cygnus, a little group shining with a collective magnitude of 7.5 and covering 10.0’ of sky. Under suburban conditions, a 4-inch telescope will reveal maybe 20 stars on a superior night. A larger instrument will show more, but not many more. And yet, and yet… I’ve always liked this cute little sucka. Maybe because its stars are arranged in a distinctive dipper-like pattern, like a miniature M45:
M 29 is immediately identifiable in a 22mm Panoptic eyepiece in the C11. Basically a small dipper asterism with 8 prominent members and perhaps twice that many dimmer ones that might be members of the group. Going to 220x pulls out more a few more stars. Fills about half the field of a 12mm Nagler. This cluster is attractive and stands out well tonight at high power, but it's best at the lower magnifications.
Good one alert! Good one Alert! M30 doesn’t get tremendously high in the sky in the Northern Hemisphere. It’s situated in Capricornus at a declination of -23, but its magnitude of 6.9 coupled with a modest size of 12.0’ means it remains prominent.
I’ve always called this one “the Goat Cluster,” and not because of its location in the Sea Goat. On any passable night with a 6-inch or larger scope, you can see two streams of stars coming off the core that—amazingly—resemble the horns of a goat. While the cluster doesn’t offer tremendous resolution for an 8 - 10-inch telescope, plenty of stars are still resolved. One of my very favorite fall objects.
Good God, what can you say about this awesome thing? It is high in the sky for northern observers and is shining at magnitude 4.3. Unfortunately, it extends a huge 2.6-degrees. That doesn’t harm its brightness; I could often see it naked eye on a clear, dry night from old Chaos Manor South in Mobile’s Garden Historic District downtown. It’s not brightness or lack thereof, but that enormous size that makes “Andromeda” less than impressive in larger telescopes.
What you’ll see in your 8-inch, even at low power, is a bright ball, the central condensation of the galaxy enwrapped in bright haze. Slewing around shows lots more haze, but it admittedly it doesn’t look much like a galaxy. To make it do that, you need wide, wide field. My 80mm APO and my 25x100 binoculars are my favorite M31 instruments.
Not that larger telescopes don’t have their place with M31 when you want to zoom in on details—and there are plenty of details to be seen here. Everything from a tiny, star-like nucleus, to a massive star cloud with its own NGC number, NGC 206, to a huge system of globular clusters, the brightest of which are visible in an 8-inch scope as slightly fuzzy “stars.”
M32 is the brightest of M31’s satellite galaxies. It is analogous to our own Large Magellanic Cloud, and is impossible to miss 24’13” south of M31’s center. It’s bright and it’s slightly oval, but beyond that, details are hard to come by. It’s an elliptical galaxy, so technically there really shouldn’t be much detail to see here. On the best nights at high magnifications with apertures of 10 – 12-inches, I occasionally think I do seem to be able to make out some sort of very subdued dark features in its halo. This is, however, more than likely averted imagination.
From the suburban backyard, beautiful and graceful M33, The Triangulum Galaxy, can be tough, with only a small round central condensation being visible. That’s not surprising since the galaxy, while relatively bright, extends a whopping 61.7’ x 31.3’. I can almost always find it even from yucky skies, however, if I am careful in positioning the scope 4 degrees 15.0’ northwest of Alpha Triangulii, the apex of the triangle.
From darker skies, M33 is an entirely different story. Not only does a 10 – 12-inch easily pick out its loose spiral structure, several HII regions, most notably NGC 604, a huge analog of our own Orion Nebula, become visible. This is one time you might want to use a UHC filter on a galaxy. It will dim M33, but make its nebulae pop right out. Further enhancing the view (without the filter) are numerous dim stars sprinkled across the galaxy’s face.
Ho-hum, it’s a ho-hummer. I’ve never been a big fan of M34. It’s just too large at 34.0’ to be very striking in an 8 or 10-inch telescope. It’s also set in a rich field and the cluster stars don’t jump out at you as much as you’d think they would even in a wide field instrument. And yet, I must admit that with a 35mm Panoptic eyepiece in Zelda, M34 can be striking, showing maybe 40 bright stars, many of them arranged in curving arcs. “Striking,” yeah, but not “blows you away.”
We’ll end on a high note. Gemini's M35 is one of my superstar open clusters. Not necessarily because it is the most beautiful of the Messier galactics—it’s very rich but a little large at 25.0’ across when compared to nearby M37. It’s that there’s a bonus object here, little NGC 2158, a much dimmer and more distant magnitude 12.2, 5.1’ group located less than half a degree from M35’s center. With a wide field, you get this tremendous sense of depth while viewing the two. A 10 – 12-inch is able to resolve many faint stars in NGC 2158 at higher power. I could even see a few from Chaos Manor South with Old Betsy.
Next time? Next time Messier wise will be in part the marvelous Auriga Trio, M36, M37, and M38. Before I do that, though, I am still planning on bringing you the latest installment in my (some would say scandalous) ongoing love affair with refracting telescopes.
Sunday, April 10, 2016
Issue #488: The Truth About the Magazines
The truth about the magazines? Those of you who know me might nitpick and say, “Well, maybe the truth about one of the magazines. Sky & Telescope.” I have never written for Astronomy Magazine, you see, the other big U.S. amateur astronomy monthly. However, I do know several of the Astronomy regulars, and even if I didn’t, the things I am going to talk about here are hardly specific to Sky & Telescope. In fact, many of these things apply not just to our astro-rags or the big UK mags like Sky at Night and Astronomy Now, but to any hobby related magazine be that CQ or Model Railroading. And, indeed to magazines in general.
What’s the why and wherefore of this morning’s blog? I frequently get my goat got when I read the wrong and wrong-headed comments about the astronomy magazines I see on a certain astronomy BBS (spelled “Cloudy Nights.”). Certainly, the posters there have the right to their opinions, but often these opinions are just, well, wrong, and are formulated by people who don’t know anything about the magazine biz. The Internet being what the Internet is, however, these opinions sometimes get repeated enough that they assume the mantle of truth: “EVERYBODY KNOWS,” blah-blah-blah…
Disclaimer: The following is just my opinion, and you know what they say about opinions.
These are not Fortune 500 companies.
Some years after I began writing for Sky & Telescope and their (then) sister publication Night Sky, after I had begun to think my future in astro-writing probably lay more in the magazine arena than in doing more honest-to-god books, I visited the old S&T editorial offices on Bay State Road in Cambridge, Massachusetts. I’d known what to expect, sure, but I was still a little taken aback that this world class publication was not housed in some towering edifice like the HQ of Time Magazine in its heyday. Instead, Skypub was situated in a smallish 1960s style industrial building and a couple of old houses next door to that.
No, there is no giant office at Skytel filled with desks and scurrying staffers àla How to Succeed in Business Without Really Trying. The astronomy magazines are a dozen or so full-time staffers backed up by more (but not too many more) regular contributors, “Contributing Editors” in the parlance. Costs go up, head count has to go down, and the product still has to remain good. It’s amazing what gets done by a few committed folks in these latter days.
Yes, both Sky & Telescope and Astronomy are now owned by larger corporations, but their parent companies are still small potatoes, to say the least, compared to Time-Warner or some such giant or former giant. Let this be your guide to what is possible. The two are small hobby magazines serving a very small market—maybe 200,000 somewhat serious amateur astronomers in the USA. That means the magazines’ resources are limited and that is unlikely to change.
Yes, I believe both will continue to adapt and survive, even if that means someday —hopefully far in the future—abandoning print publication for e-only. But unless the population of amateur astronomers suddenly explodes, I believe the status quo will remain the status quo. So, don’t look for big increases in page count. It is just not feasible.
This is not a good time for magazines of any kind, not even hobby magazines.
Have you been to the newsstand lately? Like in Barnes and Noble or Books a Million? Have you looked closely at the magazines there? Some seem to be doing OK, mostly one-shot “entertainment” rags, publications about movies, especially genre movies, and about celebrities. They are fat and glossy. But have you looked at the prices? They are freaking outasight. Gotta be to make these projects marginally profitable. If anybody is doing well in the business, it’s these entertainment magazines, but it is very unlikely that many of them would survive as monthlies without being radically pared down in page count. And even then...
How about the familiar old reliables, the monthlies and the weeklies that have been on the racks since forever? The news magazines are sad and pitifully thin. Those that remain. They will all soon be gone. Hobby magazines like S&T or Astronomy or Popular Photography or Analog or anything similar? They have also shrunk in this day of high publication costs, but not to the extent of a Time Magazine and are hanging on—for now.
What is killing news magazines and anything remotely like them all the way from TV Guide to National Geographic is obviously the Internet. Why buy a cow when you can get the milk for free? The same thing that did in the newspapers. Their time is just passing.
Less affected but still affected by the Internet are hobby magazines of all sorts. There are tons of websites where you can get plenty of info about your particular passion for free. Frankly, what is amazing is that both Sky & Telescope and Astronomy Magazine have managed to keep their page counts and quality up as well as they have. There is a reason for this relative success that most of us will acknowledge if we really think about it.
Free sites on the Internet are not (necessarily) a replacement for a quality magazine.
What’s keeping the astro-mags alive is that when compared to the Internet they are just a much more authoritative source of information on our avocation. I’m sure you read the aforementioned Cloudy Nights BBS, and it is great. But it is not Sky & Telescope and it is not Astronomy either. There are plenty of smart people posting on CN, sure, some of the top people in our avocation as a matter of fact. But there are also people posting there who couldn’t find their you-know-what with both hands. It is the nature of an online forum, though, that the views of those who know, and the views of those who only think they do can seem to have equal weight, especially for novices.
Unfortunately, novices are both most likely to need help and advice and are also most vulnerable to being steered wrong. That can be serious business indeed, and has more than once even lead to promising new recruits (something we need badly) dropping out of the hobby.
In the past, I have summed this up, the question of what’s an authoritative source for information on our hobby, with one simple question, “Who would you rather get advice about telescopes from, Dennis di Cicco at Sky and Telescope or Joe Spit the Ragman at Cloudy Nights?” Again, this is not to say CN is a bad thing; it can be a very good thing. But when you need advice you can rely on, you are still well advised to go to S&T.
I know you love Sky & Telescope (or Astronomy) but it is not just your magazine.
One of the complaints I read frequently goes like this, “Why won’t they print the articles we want to read? Like about measuring double stars with filar micrometers (or building Gregorian telescopes or whatever)?” The reason is that the magazines have to appeal to the general audience of amateur astronomers. That doesn’t mean there are not specialized pieces on specialized techniques or interests now and then, just that you can’t expect your pet esoteric interest to show up in every freaking issue. That is what the Internet if for.
Yes, there is most assuredly a place where the Internet, whether Sky & Telescope’s website or Astronomy Magazine’s website or a page you put up yourself, excels: narrowcasting. Serving the interests of the few. Magazines can’t do everything, and expecting them to be able to do everything is silly.
Don’t see what you want? Let ‘em know.
Just because you haven’t seen a story about micrometers in your favorite magazine doesn’t mean there never will be one. The editors of the mags try to keep their fingers on the pulse of the audience, but Mr. Editor is not a mind-reader. Write a letter or an email and let ‘em know what you want. Encourage your double star measuring happy buddies to do the same, and you very well may get what you’re after. In my experience, both magazines listen. They’d be foolish not to.
Advertisers are the lifeblood of any magazines.
OK, I’ll fess up: I am something of a gear head. I don’t put equipment ahead of observing, but I sure like looking at cool new astro-stuff. That means that I like “all the ads.” Some of you don’t, however, and are concerned that the advertisements are forcing the editorial content out. That is not the case. The ratio is still roughly the same as it’s been for a while. And even if you don’t like to look at Acme Telescopes’ full page color ad extravaganzas, realize that advertising is, along with subscribers, what keeps the magazines alive.
Not at Sky & Telescope, anyhow, and I hope and presume nowhere else. There’s an old canard that I hear repeated over and over and over, frequently on Cloudy Nights, “They’ll never give Acme Telescope Company a bad review. Acme runs all those ads in their magazine you see.” Wink-wink. I’ve heard this story at least since the 80s, if not before. And this “fact” is now common knowledge according to some of you. But the thing is, it ain’t true.
I have written reviews, Test Reports, for S&T and I can tell you one thing: I have never been asked to go easy on a product, to tone down criticism, or anything similar. Never. So why do people choose to believe this story? Some people just assume (and you know what they say about that word). Others are children of the Internet, where a review often goes like this, “Damn that fraking Acme. Their equipment is crap. Screw them!” People are now used to over-the-top in online gear “reviews.” They expect it, even if it’s not professional or objective and helps no one. When they do see an objective and professionally written review, they tend to think the writer is going easy on a product.
We remember the magazines as being different from what they really were.
Whether it is the Sky & Telescope of the 60s or the Astronomy Magazine of the 70s, some of us choose to believe the grass was greener back then. The articles were more technical. There was oodles of math. They didn’t talk down to us. Why, it was real astronomy! The truth, you’ll discover if you actually go back and read those old back issues, is somewhat different. I will admit that both magazines are livelier both in style and appearance than they were back then, but that is not a bad thing.
S&T was a fine magazine in the 60s, and I loved it, but I would much rather look at and read today’s product. Was the technical level higher? If it was, it wasn’t by much. Ground truth? Sky & Telescope, which is generally considered to be at a considerably higher technical level than Astronomy, has still never, ever been The Astrophysical Journal. If you need that, trot to your local university library and revel in the ApJ stacks.
The people working at/for the magazines are your allies, not your opponents.
Sunday, April 03, 2016
Issue #487: Let’s Have Some More Ms
First of all, I was much gratified by your huge response to last week’s article. The emails and Facebook messages I received concerning it were reassuring in that they showed I am not the only one who’s still worrying about the goto wars. More than that, I was happy to hear most of you think the same way I do about the subject. You, like me, mostly think what matters in amateur astronomy is a person’s love for the night sky; everything else is secondary.
But that was last week. This week? The promised refractor piece will run soon, but not this time. Seems that in addition to comments on the go-to wars story, I’ve been getting one heck of a lot of clamoring for MORE MESSIERS, and who am I to say “no” to deep sky hungry amateurs coming off a resolutely cloudy winter?
We start out with a bang. Well, sort of. While the famous Trifid Nebula is one of the highlights of the Messier catalog, its dirty little secret is that it pales in comparison to the nearby Lagoon, M8, just a degree and a half to the south. M20’s listed size, 28.0’, and magnitude, 5.0, make it sound a little more eye-popping than it actually is—in fact, I believe the 5.2 probably has more to do with the open cluster involved in the nebula than the nebula itself. Let’s not dance around the issue: as Messiers go, the Trifid is on the dim and more difficult side.
At least finding M20 is no problem. From a decent site—and “decent” does not mean your magnitude 4 backyard with the Trifid smack down on the horizon—just scan “upward” from M8. Even if the nebula doesn’t quite show up in your finder, you should see a fuzzy something in a low power eyepiece. The exact nature of that something will, however, vary with your aperture and your sky quality.
Undoubtedly you will notice a little bit of fuzziness around the bright double star V3791 Sgr, located near the heart of the emission component of the Trifid. The darker your site and the larger your telescope, the more the view will expand outward from there, from the basic cloud, to the dark lanes radiating from it that give it its Trifid moniker.
In a 10-inch or larger telescope under excellent skies, you may be able to divine that there are actually four “petals” of nebulosity rather than the three implied by “trifid.” And if you have really great skies, you may also see the reflection component, the blue part of the nebulosity, lying on the Trifid’s northern side—ain’t easy, though.
While a medium aperture telescope and very dark skies are best for an impressive look at M20, you sometimes get an exceptional view with a smaller telescope as I had one evening at my club’s (semi) dark site:
NGC 6514 is the cluster involved with M20, the Trifid Nebula. Its slightly sparse stars are fairly attractive, covering some 28' of space. The interest here if, of course, is the nebula. It's remarkably good tonight, with the dark lanes standing out better than I have ever seen them in the C8. Occasionally I get hints of the reflection nebulosity, including hints that it is blue.
The Trifid nebula responds well to a UHC type filter, by the way. Well, the emission component does.
Naturally, a filter totally erases the reflection nebula.
|Ah, those wide Milky Way Vistas!|
It’s slightly unusual for successive Messier objects to be near each other in the sky, but M21 is indeed adjacent to M20, lying about ¾ degree to the northeast of the nebula. What’s it like? I am not a big fan of sparse open clusters, and tend to be somewhat unimpressed by this one. It’s bright at magnitude 7.2, yeah, and relatively compact at 14.0’, but there just isn’t much here. With my 10-inch Dob, Zelda, in the backyard, I can make out maybe 20 – 25 suns sprinkled here and there.
There is, however, a way to make M21 look really, really good: binoculars. Not just any binoculars, but giants. With my enormous 25x100 Zhumell Tachyons from the dark skies of Chiefland, Florida, this whole area is a wonderland, with M8 to the south and M21 to the north bracketing M20. And oh how good M21 looks at low power, a beautiful knot of sparklers at 25x in a wide, wide field.
Oh. My. Freaking. God. When we were talking about M13, I think I mentioned that M5 and M22 are very competitive rivals for the title “Best glob visible in the Northern Hemisphere.” And I believe I at least implied M5 was ahead of M22 in that race. That is true, I suppose, if you live much above 35-degrees north or so. South of that and it begins to be a different story with M22 easily pulling ahead.
At more southerly latitudes, this big, bright, elongated thing (32.0’, magnitude 5.2), just dominates. Shining bravely next to the lid of Sagittarius’ teapot, it draws me in every time I am in the area, as it did not long back when I was taking a visual cruise of the south with my C11:
M 22 is low tonight, but still wonderful. Big oval globular. The central region is loose and large as compared to the halo of outlying stars—the core really dominates visually. Very well resolved. TeleVue Panoptic 27mm, 103x.
One other really great thing about M22? You don’t need a C11 to enjoy it. Years and years ago when I’d just got my Short Tube 80mm refractor, I was out in the semi-dark suburbs seeing what it could do. M13? Not so hot. No resolution that I could see no matter how far I pushed the magnification (100x was really about the limit for the little thing before the optics began falling apart). Not one lousy star. M22? That was different. Despite being far from culmination on a spring night, I could see more than a few stars in its halo. Thanks to its loose (but not too loose) Shapley Sawyer type, VII, this glob is easy to resolve even in my 66mm ED scope.
|Wide field M22...|
Continuing to the north from the Teapot for 4-degrees, we come to our next M, another open cluster. M23 is located at the center of the small Sagittarius star cloud, and that is an important distinction. It is located in the star cloud, it is not the star cloud.
Otherwise? This is a large and relatively dim cluster, magnitude 5.9, 29.0’ across. Some of its stars are in fact dim enough that they masquerade as nebulosity in a smaller aperture telescope, but there is no real nebulosity involved here. In my C8, I see a couple of dozen suns laid out in a fairly shapeless fashion. Frankly, the only thing that saves this one is the basic beauty of the area. Other than that, check it off the list and move on.
The nature and identify of this object has caused a lot of heartburn over the years. Old Chuck Messier described a large 1.5-degree across “nebula.” But the object, the open cluster, that has often been identified as M24 in modern times is a mere 6.0’ across. What the—? It seems certain Messier was not describing a smallish galactic cluster, but something else altogether, namely the Large Sagittarius Star Cloud, a brighter portion of one of the Milky Way’s arms. As with M23, “M24” is in the star cloud, but it is not the star cloud.
So, you wanna see the real M24? Get those binoculars—15x70s do a good job on it from a dark site—and scan to the north-northeast of the Trifid. When you notice what looks like a detached portion of the Milky Way, you are there; you have conquered the object Messier recorded.
If you like, however, you can also have a look at its usurper, NGC 6603, a thoroughly undistinguished open cluster with a magnitude of 11.10 (!). Not that it’s that bad. In the 12-inch under very dark skies, NGC 6603 is a nice, rich, small clump of suns that looks sorta pretty. It’s just not M24.
Searching around on the Internet, you may be surprised you don’t find much about our final Sagittarius galactic cluster for the evening, M25, and especially not drawings of it and log entries about it from your fellow observers. That’s because this magnitude 6.2 open cluster located 8-degrees 12.0’ due east of M23 is on the large side, 29.0’ across, almost the size of the Full Moon. While it is fairly rich, its stars are still somewhat spread out and it is not really very well detached from the starry background. That makes M25 more fun in big binoculars than in your main telescope (in the summertime, I always bring binocs with me when I go out observing). Nevertheless, the cluster still has its charms in a scope:
Nice bright, LARGE open cluster. Best at lower power. 40-50 bright stars visible, filling the field of a 35mm eyepiece in the C11.
Still, the 25th entry is rather staid, with its major claim to fame being that it is one of only two Messiers that don’t have NGC numbers. Maybe Mr. Herschel also thought this one was kinda ho-hum, too.
Crikey! Not another open cluster? Yep, and not a good one. Scutum’s Messier 26, at magnitude 9.0 and 7.0’ across, is small and dim in binoculars. In a smaller scope, 4-inches or less, it looks a lot like a distant, unresolved globular cluster. Or maybe a little comet sans tail, which is likely what got Messier’s attention in the first place.
In an 8-inch or 10-inch aperture telescope, M26 is somewhat better. You’ll maybe resolve ten stars, but that is it no matter how much you crank up the power. How do you find the thing? The easy with is with go-to or digital setting circles, but it’s not overly tough to get on M26’s position the old fashioned way, since it is only 49’ east-southeast of reasonably bright Delta Scuti.
|M27 with a C8...|
Best for last. What’s the best planetary nebula in the sky? Sorry, M57 fans, it is M27, the Dumbell Nebula in Vulpecula. The only bad thing about the Dumbbell? It can be a little hard to locate under poor skies since it lies among the subdued stars of the Little Fox just to the southeast of the magnificent Northern Cross. However, even under fairly poor conditions it’s not too hard to run down, since this planetary nebula is both big and bright, magnitude 7.3 and 8.0’ across its longest axis.
I’ve been observing this one since I was a boy and it has simply never disappointed. Not in my Short Tube 80, not in my 12-inch Dob, not in any telescope I’ve turned to it. It is a wonder, an apple-core shape of nebulosity floating in a rich and beautiful field. There is always more to see here—clumps of nebulosity, tiny stars enwrapped in the cloud, even a doable if not easy central star that shines at mag 13.5.—so I never tire of admiring its lustrous beauty.
Tips? If you want to see more of the nebula, try a UHC type filter (including the Orion Ultrablock). The beauty of a UHC is that it brings out more nebulosity without dimming down the field stars and making the view less attractive. Yes, an OIII will work, but it really tamps down those stars. With the UHC in the eyepiece of my 10-inch Dobsonian, the nebula doesn’t look like a dumbbell or an apple core anymore. The side lobes fill in and suddenly what we have is the (American) Football Nebula.
Eyepieces and magnifications? I like a wide-field for this one, since that just enhances the spectacle, taking in more and more of the rich Vulpecula star field. My Panoptics do a good job here. As for power, that depends. I like to go back and forth between closeup views and wide vistas, hunting for details one minute, and just drinking in this thing’s majesty the next.
And that, then, is it for this time. Going on to the nextun would mean hitting yet another summer open cluster, and I have really had enough of them for now. One nice thing about this bunch? You will actually be able to go outside and take a look at them before long. Right now Sagittarius is not well up over the eastern horizon till after 4 in the a.m., but he is back, and he will soon be creeping into the evening heavens. You’ll be able to marvel at all of these pretty Ms soon. Well, assuming we get some clear skies over the course of an el Niño summer, and I must admit I am a little skeptical about that, alas.