Sunday, September 30, 2007

 

Uncle Rod, Astrovideographer

It ain’t like video technology is new to astronomy. Amateurs have been using TV cameras to capture the sky since semi-affordable vidcams and recorders first became available way back in the 70s. It didn’t really take off until the coming of the inexpensive camcorder in the 1990s, however, when planetary observers began using video to capture the Solar System in astounding detail, putting to shame anything that had heretofore been done by film imagers—amateur or professional. But we—we “astrovideographers” as we were beginning to call ourselves—wanted more. We wanted the deep sky.

The experts were quick to say we were cuh-razy. Video, exposing at a nominal 1/30th-second, didn’t have a prayer of capturing even the brightest deep space objects. FUHGEDDABOUTIT!

Huh! We set out to prove those bright boys wrong. Our first approach was to try what the Solar System mavens were doing with great success: stacking hundreds—or thousands—of individual frames via garageware like Astrostack and, before long, the wonderful Registax. That didn’t work quite as well on the deep sky as it did on the planets but, still, it wasn’t long before some talented individuals were producing at least recognizable images of M13 and M42 and sharing them on the Yahoogroup that served as information exchange, Videoastro (still going strong).

There things remained for a little while. Deepsky videoing was somewhat doable, especially with the help of new CCD chips like the Sony ExView series, which were amazingly sensitive, and which were quickly followed by even more light-hungry silicon. The breakthrough didn’t come, though, until a pair of small companies, Adirondack Video Astronomy and Mallincam, began selling what they were calling “deep sky video cameras.” Not only did these use low-lux CCDs, they were able to integrate for far longer than 1/30-second. Today, there are few deep sky objects beyond the reach of the companies’ current top-of-the-line cameras, the Stellacam III and Mallincam Hyper Plus.

So the Mallincams and Stellacams can image the deep sky? So what? What can they do better than a real CCD camera like an SBIG or Starlight Xpress? What they can mainly do better is present a near live view of the deep sky. Set the Stellacam’s integration time to 256 frames, for example, and the image on the monitor is refreshed about every 10 seconds. There’s no computer processing—or computer—required, either. Any TV or monitor capable of accepting composite video inputs can display the outputs of deep sky cameras. Frame, focus, push the “go” button, and DSOs appear on the screen in startling detail.

I often hear folks extolling the value of video for public outreach, and there’s no doubt about its worth in that regard. I’m sure we’ve all had the experience of trying to show a 6-year-old M13:

“Put your eye right up there, sonny. See it?”

“Uhh…”

“It ought to look like a ball of stars. Don’t you see anything?”

“I think I see something.”

In your heart you know this kid and many like him haven’t seen a danged thing. It’s hard for the itty-bitties (and many adults) to see pea-turkey of the deep sky their first time at the eyepiece. Video cures all that. Not only can they see all those wonderful objects as well as anybody else; to kids those galaxies, nebulas, and star clusters frankly are much more appealing on TV than in an eyepiece:

“Mommy, come look. These stars are real; they’re on TV!”

Another argument for deep sky video is that it helps the average light-pollution-plagued amateur to at least see some stuff from home. That it does. Back when our club was using a badly compromised in-town site for monthly star parties, I struggled to see details in even the brightest Messiers. If you held your mouth just right, a 20-inch might show a hint of M64’s black eye. Video? On the worst nights, My C8 is capable of displaying M64’s black eye, M97’s big eyes, and much more that escapes even the biggest of the Bigdobs under the same compromised skies.

But, like they say on them late-night WTBS commercials, “That’s not all!” Video ain’t just for light-polluted backyards. At dark sites it acts as an aperture multiplier. The Stellacams and Mallincams have the effect of, on average, multiplying your scope's size by about 3 times. Not many of us would care to haul around (or be able to afford) a 33-inch scope. Most of us can, however, afford and transport a C11. No, I’ll admit it’s not exactly like viewing through the eyepiece, but the difference is not as great as you might think. Deep sky video has a “look” that’s closer to the visual than to CCD shots. On video, globular clusters, for example, have cores composed of hosts of tiny stars. In the average CCD image these cores are burned-out blobs.

Not that video is the be-all and end-all. While many astrovideographers capture video frames and stack these into decent images like my shot of the Eagle Nebula above (go to my CCD page and scroll down for more), the best video stills are of lower quality than those from cooled integrating cameras or DSLRs. Video is not standing still, however, and, in addition to longer exposures, the most recent Stellacams and Mallincams feature peltier coolers to reduce noise (color is also here now). For the moment, however, "best tool for the job." If you want stills, get an SBIG or a Canon. If you want live views or video to view and admire at home get a Stellacam or Mallncam. Finally, the chips on both the Stellacams and Mallincams are still relatively small in size, so an f/3.3 focal reducer is de rigueur for an f/10 SCT.

Bottom line for Your Old Uncle? Video has allowed me to see more more frequently than I dreamed possible. I want a look at the Horsehead Nebula? That no longer means a trip to the darkest of dark sites with hbeta filters and ST2000s; it’s just a quick jaunt out to my semi-dark club site where I can view Horsey—and show him to my buddies—any time that silly old nag is over the horizon. That’s, in a nutshell, why I’m getting more and more hooked on deep sky video all the time. Yeah, I still like an eyepiece view, but you know what I like even better? Seeing more.

Wednesday, September 12, 2007

 

Off the Beaten Path: The 2007 ISP...

Sometimes it pays to get off that beaten path—at least when you’re in search of a great star party experience. Sure, we all know about the TSPs, the WSPs, and the Stellafanes, great star parties all and justly famous. But there’s plenty more out there, including some far less well-known venues with great skies that attract smaller crowds and feature more relaxed and informal atmospheres than the big dos can. The Idaho Star Party, for instance.

Idaho Star Party? What does this ol’ boy know from Idaho? Not much at the time I was invited to be the keynote speaker at this year's 23rd edition. Oh, I knew where Idaho was—sorta, anyway—and that they grew potatoes up there (right?). That was about it, though. I pictured something along the lines of a far west Iowa. Lush farmland, but with ‘taters instead of corn.

I didn’t see much of Boise on my first night there. I was delivered into the friendly hands of the BAS (Boise Astronomical Society, natch) after dark after a somewhat punishing and long series of flights from Possum Swamp, and didn’t see one hail of a lot except the insides of my eyelids till the next a.m.

When I was conscious again, more or less, man was I surprised. I was way-out-west. The sparkling clean little city was ringed with impressive mountains, and a slight throb in my noggin signaled “high altitude” (either that or that I needed a drink). That and the clear air (occasionally tinged with the scent of burning from area forest fires) spelled g-o-o-d s-e-e-i-n-g to me. I was beginning to get excited.

Arriving at the ISP’s current site, Bruneau Dunes State Park, about an hour from Boise, kicked the excitement factor up another notch. Sure, dark skies are great, but without good facilities to go along with them what do you have? Not much. Thankfully, ISP’s site is way above average. In addition to plenty of RV hookups (RVs and travel trailers seem to be the favored accommodations for western star partiers), there were a couple of pin-neat little cabins (one of which would be my home for the next couple of days), an observatory containing a 25-inch Obsession, and a modern classroom building perfect for presentations.

The skies? As above, there was some intermittent haze due to area fires (thankfully distant), but mostly very, very good mag 7 (zenith) conditions prevailed much of the time. On that first night, after delivering my first presentation to an excellent, responsive audience, I wandered the field until the wee hours, observing with my trusty Celestron 10x50s or with any telescope I could beg, borrow or—well, never mind. Deep sky heaven? You betcha. I observed until I couldn't observe no more, turning in right after snapping the above shot of the Moon and Venus and a spectacular western Sunrise.

Next morning, I got the stars out of my eyes (temporarily) and took a more-better-gooder look at my surroundings. The site is called “Bruneau Dunes” for good reason. Just to the southwest of the observing fields are mountainous sand dunes. These ring a pair of semi-man made lakes, and are the result of the odd and interesting geology of the site. Basically, the region is the ancient bed of a long-gone inland sea or huge lake.

The most outstanding feature of the ISP, though? The friendliness of the organizers and the rank and file. Your Old Uncle was far from home and feeling a little tentative in his new surroundings. That didn’t last. Barb, Eric, Ray, Fred, and all the rest of the good folks (you know who you are) soon had Rod feeling like one of the gang. I’ve long said the best part of a star party ain’t the observing; it’s spending time with the amateurs you meet there. That was certainly true for ISP—in spades.

Yeah, making new friends and rediscovering old ones is the best part of a star party. What’s the second best thing, though? BUYING ASTRO STUFF, of course. ISP was blessed with several good dealers this year including Teton Telescope and Buyastrostuff.com. You know dang good and well I—and a lot of other happy amateurs—couldn’t resist partin’ with at least a few hard-earned greenbacks.

All too soon, though, I found I’d finished my second presentation of the star party, the kick-butt star-b-que was over, and another night of excellent deep sky observing was begnning to wane. I’m always anxious to get home to Chaos Manor South, but this was one star party I was real sorry to leave behind. Great skies, great folks, great surroundings, no bad surprises (well except for the black widow spider who decided to pay a courtesy visit to Unk in his cabin!). How could I not be sorry? ISPers: thanks for a great experience; hope to see y’all again soon!

Wanna see more ISP pix? Just click!

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