Sunday, September 14, 2014

 

Destination Moon Night 7: Obscured by Clouds


No, you can't always get what you want
No, you can't always get what you want
No, you can't always get what you want
But if you try sometime, you just might find
You get what you need…

Jagger - Richards

One thing I swore when Miss Dorothy and I moved out of glorious old Chaos Manor South, the original Chaos Manor South, the Old Manse, was that I would make up for all those long years where my observing had been limited due to work and the skies and trees of downtown Possum Swamp. I won't say I’ve been out with a telescope every cotton-picking clear night since we relocated to Hickory Ridge, but near about (not that there've been that many of them since spring). I’ve even done some fairly ambitious work from my backyard here at the New Manse.

That includes some things I hadn’t done from home in twenty years. Like prime focus deep sky imaging. Yeah, I did a fair amount of lunar and planetary photography from the Garden District till the trees finally hid the sky in the late 90s, but deep sky? No way. I wouldn’t have dreamed of trying. Out here in the suburbs, it’s an entirely different kettle of fish, y'all.

I found out soon after we moved in that I could do plenty of video work. The bright objects were no problemo, as my Mallincam Xtreme /AstroLive snap of M57 shows. On those so far rare occasions when I get a cloud and haze free evening, I can go considerably deeper. Yes, I have to use a filter, the Orion Imaging filter, a mild light pollution filter like Lumicon’s old Deep Sky filter, to tone down the bright background a hair, but I expect the Mallincam may surprise from the backyard with the clearer (maybe) skies of fall and winter.

Ring with Xtreme...
Assured that I could see something with the video camera, I began to wonder about prime focus DSLR imaging.  A Sky & Telescope assignment impelled me to stop wondering and see what I could get with my Canon from home. Verdict? Not too shabby. I probably should have imaged at an ISO a stop faster than I did, but my results were surprisingly good given the presence not just of haze, but a near full Moon.

Let me also say rat-cheer that the new PHD Guiding, PHD Guiding 2, shore didn’t hurt none. If you don’t have a copy of the latest edition of amateur astronomy’s best-loved autoguiding program, get it right now. It’s still free, y’all.  Impossible as it may be to believe, PHD 2 is even better than the original; it just LOCKS ON to that consarned guide star.

Assignment done, I lollygagged through quite a few evenings—most of them cloudy and none of them good enough for pitcher taking—till one night when I began to think about my good, old Atlas mount. Last time I’d used my much-loved heavyweight GEM at the Possum Swamp Astronomical Society dark site, the previous winter, I’d had problems.

On that night, I’d gotten inconsistent results while using the EQMOD program to control the mount. The goto alignment would work OK, but shortly thereafter, the mount would get confused, pointing every which-a-way. Which was disturbing, since I had never had a minute’s problem with EQMOD.

What’s that, Skeezix? You don’t know what an “EQMOD” is? Have a look at this old blog entry from Unk’s vault of moldy oldies, but, in short, it’s like NexRemote. It is a program (technically an ASCOM driver) that takes the place of the hand control and adds many new features to the Atlas EQ-6 (it will also work with the Sirius HEQ-5, the AZ-EQ-6/Atlas Pro, and Synta’s new EQ-8 and the Orion version of that big mount). It even lets you use a wireless gamepad as your “HC,” just like NR.

I have almost always used EQMOD for imaging with the Atlas. It works well and I'd never had to give it a second thought  till that last time out. I believed the troubles I had at the dark site had nothing to do with EQMOD, however. I was convinced a loose power cable connection was the culprit and took pains to add some strain relief to the power cord at the mount.

Shortly after I finished the S&T assignment, I decided I’d try some prime focus imaging with the Atlas and my old C8, Celeste. I hadn’t turned the mount on since we’d moved in, and I wanted to assure myself the power cable fix had done the trick. I set up C8, Atlas, and computer, but wimped out on EQMOD. The sky looked iffy, and I figgered it would be easier to just use the SynScan HC. It worked perfectly—I had no trouble getting 10-minute guided subs of good, ol’ M13.

Still, I thought it would be a Good Thing to make sure EQMOD was again firing on all cylinders. The next semi-clear night that came, I hit the backyard with the Atlas and C8 once more. Since I just wanted to try EQMOD, I left the Canon in the gadget bag and hung my Mallincam Xtreme on the scope’s rear cell. At first ever’thing was ducky. M13 was in the center of the video screen right where he belonged. But, as before, things suddenly went south, with the Atlas not being able to find its rear end with a flashlight.

It was pretty clear now that there was something wacky with EQMOD, and I was purty sure that something was either the EQDIR module (which converts serial data from the computer to levels the mount likes) or the serial cable. Since the EQDIR and cable are both going on seven years old, I don’t have too much heartburn about replacing either one or both of them if further troubleshooting dictates I do so. Stay tuned.

At the end of them there alarums and excursions, I was tired, sweaty (it’s still in the mid 80s at night down here), and put out. I sure didn’t feel like disassembling scope and mount, and just covered Celeste and Atlas with the Desert Storm cover and retired inside to watch the Braves lose another one to the freaking Dodgers.

Late the next afternoon, I decided, given the clouds that had hung around all day, I might as well tear down the Atlas, and proceeded into the backyard. What should I perceive in the gloaming, though? That the sky was trying to clear. It was at  least giving birth to some substantial sucker holes. I further noted that there was a right purty little half Moon in the sky.  Hmm…hadn’t done any imaging for Destination Moon, my crusade to image 300 lunar features, in a while…hmm…

Well, why not? Why shouldn’t I continue my tour of Hecate? Several reasons. I was being eaten alive by the skeeters despite having lit a citronella candle (I hate burning up those rather expensive Thermacell pads and butane cartridges for an informal backyard run) and doused myself with Deep Woods Off. It was also hot, with my iPhone girlfriend, Siri, asserting that the temperature an hour after sundown was 85 and that it “felt like” 90. Most seriously, the sky was crazy-hazy. Nevertheless, on Unk pushed. I already had the scope set up so it was the matter of a few minutes to get the Toshiba laptop plunked down on the table on the deck and hooked up.

Well, hooked up to the ZWO camera anyway. I removed the Mallincam and f/3.3 reducer from Celeste’s rear end (sorry, dearie) and replaced them with my old Meade flip mirror, the 1.25-inch Meade 12mm reticle eyepiece, the ZWO ASI120MC camera, and my time-honored Orion Shorty Barlow.

Where I screwed up was I forgot to hook the serial cable to the SynScan HC so I could send the scope on lunar gotos with Virtual Moon Atlas like I did last time. Just as I was preparing to fire up the cam, I realized I’d forgot all about VMA. Instead of correcting my error, however, I decided to do things the old-fashioned way. Which was a mistake. 

With VMA, I don’t waste time imaging features I already have in the can but have forgotten about—I have notes in the program appended to every feature that’s completed. I can also use the built in ASCOM “hand control” for precise object centering. Oh, well, didn’t look like it would matter much, anyhow…another batch of clouds was suddenly obscuring Diana’s shining visage.

The clouds came, but they also went. Sort of, anyway. It was never really clear, and the seeing was never very good at all, even in the more or less cloud free intervals, but conditions were at least a little better than they had been on Night 6, and the pictures were OK, if not close to what the li’l ZWO can do on those rare good nights.

Werner and Aliacensis

Werner and Aliacensis are two nice, reasonably fresh-looking craters lying just 145km from a large and detailed crater, Walther, which, unfortunately, is not on my 300 list. Werner is a round, 70km, deep formation with steep, terraced walls and a mostly flat floor littered with scattered debris and lacking a real central peak. This young-looking crater dates from the Eratosthenian Period (3.2 – 1.1 billion years ago).

The adjacent crater Aliacensis is a little larger than Werner at 80km in diameter. It is also not quite as deep nor is it as perfectly round. It is older than Werner, having been formed during the Nectarian Epoch (3.92 – 3.85 billion years ago), and looks it, having a distinctly eroded appearance. I picked up a few craterlets scattered across Aliacensis’ floor, as well as the small off-center mountain that serves as the crater’s central peak. What or who is an “Aliacensis”? I didn’t know either. Mssrs. Chevalley and Legrand say, “[He was a] 14th century French Geographer and theologian born in France.”

Faraday, Stofler, Fernelius, Licetus

The next group was just to the south down the terminator, and was quite a spectacle even given the conditions, since going south meant I was approaching the Moon’s feature-rich southern highlands. As I likely don’t have to tell you, craters are everywhere there and figuring out which is which can be quite the challenge. I finally identified my quarry with the aid of VMA, but I sure wished I’d hooked up that dadgum serial cable.

Faraday is a battered 70km diameter crater that just missed being eradicated by two impacts that broke its walls, Faraday A on its northeast rim, and Faraday C on the south.  The main crater has a messy looking floor and no true central peak. Several craterlets are visible. The walls of Faraday are steep and fresh appearing in my picture despite the crater dating from the Pre Nectarian, 4.55 to 3.92 billion years ago.

If Faraday A and C almost wiped out Faraday, Farday’s impactor dang near took out the larger adjacent crater, 126km Stofler. Like Faraday, Stofler also comes from the Pre Nectarian time, and also sports well-defined walls that, unlike Farday’s, appear terraced. Away from the damaged area caused by Faraday, the main features of Stofler’s floor are the many craterlets and Stofler F, a sharp and round crater that has done a number of Stofler’s southwest wall.

On the north slope of Stofler is Fernelius. Due to the low Sun angle in my photos, Fernelius looks fresh and sharp. With a higher Sun, however, it is old and eroded. Coming from the Lower Imbrian time (3.85 – 3.75 billion years), it is a little younger than the previous two craters, but doesn’t look it. Its main features are a mostly flat lava-covered floor and a small crater, Fernelius B, that has broken the northern rim.

Licetus, another Pre Nectarian crater, is a 75km diameter formation 184km south of Stofler’s center. It’s a nice looking crater, and would appear almost perfectly formed save for two small craters on its southern walls that have caused considerable damage there. In addition to a group of central hills, the floor possesses a small crater, Licetus C, near the steep western wall.

Aristillus, Autolycus, and Cassini

I jogged back north and took a dip in magnificent Mare Imbrium to capture these three remarkable craters, of which Cassini is perhaps the most remarkable looking. In fact, there’s not a more identifiable crater on the Moon. This 58km formation isn’t the largest or the deepest or the youngest crater on the near side (it dates from Lower Imbrian days), but you can’t miss it sitting off the shores of Mare Imbrium not far from the great crater Archimedes.

What makes Cassini so readily identifiable is not its round steep slopes, but its floor. The flat lava-covered floor has one large crater, Cassini A that has a pair of rilles extending from it, and one smaller, but still impressive crater, Cassini B. That description doesn’t sound unusual, but as you can see in my sunrise picture of Cassini, it is just weird looking.

Off to the north, some 211km from the center of Cassini, is a crater I referred to as “Copernicus Junior” when I was a youngun and just beginning my exploration of the Moon. While not nearly as magnificent as the near side’s numero uno crater, Aristillus is still impressive and shares some things in common with its larger cousin, the fractured looking landscape around it, steep terraced walls, and a complex central peak (which you can’t see in my pic; the crater was still filled with night when I snapped it). This 58km diameter crater, like Cassini, comes to us from Lower Imbrian times.

Aristillus’ neighbor, Autolycus, is another goodie, if not as pretty as Aristillus. This nearly round 40km diameter feature is much younger than the other craters we’ve toured tonight, having been formed in Copernican times (1.1 billion years ago – present day). Anyhoo, it features steep semi-terraced walls, and a flat floor with a central mountain (invisible when I shot it).

Triesnecker

With clouds building again, back north I went to the “waters” of Sinus Medii, the small sea near the “center” of the Moon, for a look at Triesnecker. While Triesnecker is a good-looking deep crater, you don’t hear it talked about much. The main draw in this area is the Rilles crisscrossing the Mare, including the awesome Rima Hygenus and a network of smaller rilles, Rimae Triesnecker. The crater itself is admittedly fairly pedestrian. It features steep terraced walls, and, when you can see it, a flat floor with a central peak. Being from the Copernican Epoch, it looks fresh and new.

Goodnight, Moon...
Triesnecker’s image safely resident on my hard drive, the weather gods said, “Fun is fun, but done is done.” Haze and passing clouds morphed into thick, dark suckas, and Diana’s silv’ry lamp flickered and went out. Which was pretty much OK with Unk. I was damp with sweat and had been bitten by who knew how many skeeters (they love me…when we are at the dark site, my mates say Unk is the next best thing to a bug zapper light). How sweet it was to just cover the scope with a desert storm cover, and carry the laptop into the blessedly cool den where much cable TV and Yell awaited.

The next day I did my usual thing:  stacked the frames from the ZWO with Regsitax, sharpened ‘em up with the program’s famous Wavelet filters, and did some minor tweaking with Lightroom and/or Photoshop. I knew there was only so much I could expect given the conditions, but I was reasonably pleased with the results anyhow.

I may make one minor change to my processing procedure, however, muchachos. A lot of lunar and planetary workers, including Unk’s talented compadre Robert Reeves (who has an excellent article on lunar imaging in the current issue of Astronomy), are no longer using Registax for stacking. Instead, they are using a program called Autostakkert, which, they say is better. They still use Registax’s Wavelet filters, but they stack with AutoStakkert first. My preliminary tests have convinced me that AutoStakkert does indeed do a better job and that the resulting images are just better. There's a gibbous moon hanging in the sky now, and if I can get up the gumption to brave the skeeters on another muggy night, I may try to obtain more data for AutoStakkert to chew on. I will let y'all know how it goes.

Total:  74 Down, 226 to Go.

Next Time: My Favorite Star Parties: TSP '99...

Comments:
Hi Rod,
Wow you have a lot of stuff here.
I'll have to dig in
and check it out. Liked
your article in
Sky&Telescope
"Wired Astronomy". I've developed
a slow motion device for Dobsonians, ZLOMOTION,
you may have seen my ad in Sky.
I'm looking for someone to
test my system and publish a review.
Check it out at >zlomotion.com>
and let me know if you are interested.
Regards, Dan Katz
 
Hi Dan:

I'll definitely have a look...haven't I seen an ad for your system in the magazine? Anyway, I make no secret of my email:

rmollise@bellsouth.net
 
I tested out my 6" newtonian, 1986 4" AP apo, and my 80mm zenithstar mod scope on Epsilon Bootis and Pi Aquilae after reading your article. Overall the 4" apo did best. However, the 4" apo usually does poorly compared to my 5" and 130mm apos.

Ralph K.
 
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