Sunday, June 24, 2012

 

The Herschel Project Night 34


Every amateur astronomer deserves one once in a while. A good night, that is. After a couple of months of not much, your old Uncle was finally rewarded. About time too; I was all antsy to get the Herschel Project back on the road for its home stretch. Muchachos, I am pretty much done with The Project except for picking up a few strays in Coma-Virgo, which I hoped to do this past Saturday if it was clear enough to attack the list—I had my doubts.

Anyhoo, Saturday morning dawned clear, but rapidly devolved into scattered clouds. What did the dadgum Weather Channel say? They didn’t much know, predicting in wishy-washy fashion “clear to partly cloudy.” Good thing was I had plenty of time to make up my mind whether to go or stay, since Mr. Sun does not set for our longitude till 8 p.m. now. Not that there was much mind-making-up to do. I am continuing to abide by my rule:  “If it ain’t raining, head to the dark site.”

Since I wanted to do Herschels, and I wanted to do them seriously from our semi-light-polluted dark site, I would be using video. Specifically my C8, Celeste; the CG5 mount; the Mallincam Xtreme; and SkyTools 3. What if the skies obviously would not cooperate to the extent required to snag magnitude 13 and dimmer galaxies? I had a Plan B.

Synta, Celestron’s parent corporation and the maker of the Atlas/EQ6 GEM recently released a new firmware version for Atlas mount. I’ve often complained its SynScan hand control is less sophisticated than the Celestron NexStar H.C., but this new (beta) SynScan firmware goes a ways to rectifying that. It at least adds an Atlas-Sirius version of the AllStar polar alignment routine so beloved by Celestron GEM users. If I couldn’t do Herschels, I’d go visual with C8 and Atlas and see how the new software performed.

By 6 p.m. I was pretty sure I would not have to exercise that Plan B option. There were still a few clouds drifting around, but it seemed sure we would get “mostly clear” for the balance of the evening. Hell, it even felt relatively dry and cool, as if a weak cold front had passed through. I loaded up the 4Runner with the ton of gear I need for an Xtreme run and headed out at 6:45 in order to give myself plenty of time for set up.

Arriving at the site, your old Unk was doubly pleased. Not only had the kind folks who own the land we observe from mowed a nice big patch for us, that patch of grassy heaven had begun to fill up with club members. The Possum Swamp Astronomical Society is not a big outfit. There are maybe thirty folks on the rolls, about half of whom at best may show up at meetings. Dark site observing? Maybe three of us on any given New Moon run. This evening? There were five cotton-picking telescopes on the field, a major star party for the PSAS.

Before I did anything else, you can bet your bottom dollar I turned on the Thermacell bug zapper. I figgered the recent torrential rains would have spawned hordes of biting skeeters. Did they? I don’t know. The Thermacell kept me almost completely unbitten all night—the only time I became someone’s supper was when I walked away from my observing position to look through a buddy’s eyepiece. What an improvement over that lousy battery-powered Off gadget I tried a few weeks back.

When you are dealing with as much gear as I need for a video run, set-up is never Real Fun, but it wasn’t bad this evening. It still felt kinda dry and coolish, so I was not sweating. And I was excited, since I would get to try out two new additions to my equipment lineup: a full-sized Toshiba laptop and Orion’s new StarShoot Digital Video Recorder.

I’ve mentioned a time or two in recent weeks that I’ve replaced my Asus netbook for most astronomy use (I still like it for running the DSLR). The reason for that was that, much as I liked the little feller, I was tired of trying to read the small screen, especially when it was red filtered. I glommed onto a Toshiba lappie with a 17.3-inch display.

The digital video recorder was also added because of weariness. I was real tired of lugging around and powering a full-sized home DVD recorder. Not only did it suck down even a deep cycle marine battery in a hurry, it was prone to disk errors, probably due to me using it on always damp and sometimes cold observing fields. The little Orion records (for hours) on an SD memory card and will do that powered only by its rechargeable internal battery. Would the quality of its video be as good as from the DVD recorder? I intended to finally find out. I’d had the DVR for months but the weather gods had prevented even a single field test.

Got Celeste mounted on the CG5, roughly aligned the mount on Polaris when he peeped out, and cabled up mount, telescope, and the Mallincam Xtreme on the rear cell. Got the laptop going, too, but I did not connect it to the CG5. I had some problems with Celestron’s NexRemote software last time out, and while those are likely fixed now, I didn’t want to do anything that would waste time. I wanted to grab as many of the remaining Leo-Coma-Virgo Herschels as possible.

To that end, I hooked up the CG5’s hardware hand control. Which is not the controller that came with the mount; it shipped with the old not-so-hotsky, non-upgradeable H.C. The programmable hand paddle I bought for it a couple of years after that has worked very well. The only problem I’ve ever had with it was the result of me dropping it one night. The LCD display came unglued and assumed a tilted angle. Took the thing apart, straightened out the display, and glued the LCD back down with hot glue.

The single non-stock configuration tonight was an H.C. extension cable. The hand controls Celestron ships now have crazy-short cables, and while one on my programmable NexStar ain’t that short, it is short enough. With the extension in place I can have the hand paddle lying on the observing table right next to the laptop, which is almost as convenient as running NexRemote.

Since I’d be doing video, I had to set up the video monitor and the recorder, natch. While my new DVR has a built-in display, it’s only 2.5-inches across, and I figured it would be impossible to focus with that given my ever-weaker middle-aged eyes. I had a plan, though. I rummaged around The Old Manse and found a video switcher leftover from the analog cable TV days. It has five positions, but I would only need two. Run the video output of the Mallincam to it, and switch that video between the monitor for focusing and framing and the recorder for, well, recording.

My “monitor” has not changed; it’s still my little old portable DVD player. Its LCD display is big enough to be legible, its video outputs can be switched to “input” to use that LCD as a monitor, and it runs off either AC or DC. In the interest of making my setup even more portable, I thought I’d power the DVD player from its internal battery and see how long that would go. If it ran low, I’d switch it to the 12-volt jumpstart battery and inverter I would use to power the laptop. The Toshiba is pretty power efficient even given its 17.3-inch display, so I figgered it would go the rest of the evening on the full charge it would have acquired from the jumpstart battery pack.

Hokay, the brighter stars were shining their little hearts out, so it was time for go-to and polar alignment, which things, given your Unk’s forgetful and fumbling ways, are always an adventure. Honestly, though, What Could Happen tonight? I was using the hardware hand control, for god’s sake. Ha!

Started out pretty good. Fired up the Mallincam, booted the Xtreme control software on the laptop. When the camera’s 3-minute “safety timer” ran out, I checked the box that overlays a set of crosshairs on the video screen. Began two star alignment. The CG5 picked Spica over in the south-southeast and started moving that-a-way. Funny…the CG5 didn’t seem as loud as normal. Yeah, she was still making her weasels with tuberculosis sounds, but at a lower level. That was OK. What wasn’t OK was that when the noise stopped Celeste was pointing due north. What the—?

Had disaster struck? Was I done before I got started? First thing I did was power down and start over. No dice. Pointed right toward the freaking Little Dipper again. What now? All the cabling seemed secure. Didn’t get any No Response errors from the mount. Should I do a Reset to Factory Values in the H.C? Then a little voice said, “Unk, SLOW DOWN! Think about what you are doing!”

OK. I thought. The problem, it occurred to me, was that the mount was moving in right ascension but not declination. That was why the mount was quieterthe declination motor wasn't running. The OTA was pointing north because that is the dec home (starting) position. When you have declination problems, and only declination problems, the first thing to check on these mounts is the cable that runs from the declination motor housing to the mount control panel. Could it be bad?

It was bad—in a way. A month or two back I’d done my annual preventive maintenance on the CG5, which involves cleaning cable and receptacle contacts. One look at the mount’s control panel showed what had happened. When I was done with the declination cable I’d plugged it back in, yeah. To the autoguide port. Doh!

Powered off, plugged the dec cable into the dec socket, and we were off. Did a two-star alignment, ran the “point at Polaris” polar alignment routine (what came before AllStar), and repeated the 2+4 alignment when that was finished. Looked like I was in for a pretty good night of go-toing, since alignment star number two was in the field of the Xtreme when the slew stopped.

Only a go-to can be the proof of the dadgum pudding, though. Turned off the crosshairs on the video and mashed “M003” into the H.C. When the weasels stopped their whining, there was the cluster smack in the center of the screen. Leaving the Xtreme set at the x128 “sense up” exposure (equivalent to about 2-seconds), I focused up using Celeste’s JMI Moto-focus. That went real easy, testament to the good seeing we were experiencing now and then. When the stars around the cluster’s center were as tiny as I could get them, I bumped the Xtreme up to 15-seconds of exposure for the first (test) shot of the night.

That ol’ granpappy of a spring globular looked great on the monitor. Would I be able to record him, though? One thing I really like about the tiny DVR is that in addition to a standard wireless remote, it has what Orion calls a “one button wired remote.” That’s just what it sounds like, a button that plugs into (non-intuitively) the AV-out jack. Mash the (locking) button and the DVR turns on and begins recording. Release it and the recording stops and the DVR turns off. I could see how that might work for me.

How did that work? Purty dern well from the get-go. With M3 looking just the way I wanted it, I mashed the button on the switcher to send video to the recorder (reckon a splitter might be even better). I pushed the wired remote button, and, pretty as you please, the DVR came on and began saving M3 to its SD card. One surprise? Yes, the screen on the StarShoot is small, but it is also rather sharp and clear. With my highest power pair of reading glasses, I could probably have focused accurately with it. The DVD player’s monitor is nice for showing pretty stuff to my buddies between Herschel faint fuzzies, though.

And so it began, Night 34 of the Herschel Project. I hit the road in western Leo, knocking off any stragglers there before they disappeared over the edge of the world, and worked my way east in the Lion. Standouts? A couple of nice pairs of galaxies, but nothing that really knocked my socks off. I did allow myself a quick peep at M65 when I made my way to the hindquarters area.

How did I work the list with my new equipment? I’d frame the object to my liking if it needed adjustment on the monitor, switch to the DVR, punch the button and record for 30-seconds, write the fuzzie’s number in my notebook, check him off on SkyTools 3, squint at the computer screen for the next one (not much squinting required with the new laptop), enter that into the NexStar hand control, and repeat for just as long as I could go.

One thing that was nice on this night was that I didn’t have to do much adjusting of the mount to center targets. The CG5 was right on the money all evening. Every object I asked for, all night long, from horizon to horizon, was somewhere in the field of the Mallincam, most often closer to the center than the edge.

I continued with Leo as long as possible, knowing that every one of the remaining galaxies I could knock off would be one less I’d need to try for in the gloaming next month. And then the cotton picking clouds shut me down. At dusk there’d been a distant line of something on the western horizon, and that had how grown into a mass extending 20+ degrees up the sky. To top it off, lower clouds were drifting in from the east and heading straight for Leo, naturally.

I cooled my heels for a few minutes, chugging a Monster Energy Drink, but soon gave up on the Lion and moved to Virgo who was riding high and in the clear. When I think “Virgo,” I naturally think “galaxies,” but beyond the bright showpieces, I also tend to think “boring galaxies.” Sometimes it seems The Virgin is nothing but hordes of little elliptical fuzzballs. There are plenty of those, but tonight Willie and Sister Lina led me to some of the best (dimmer) objects in the constellation. Particularly nice was one that flitted through the Herschels’ eyepiece on the evening of March 15, 1784, NGC 4452 (H.1.23). It is the cutest, skinniest, most perfect-looking little edge-on I ever did see. It lies about 50’ southwest of big mutha M87.

Prime non-Herschel target for the night? The bright supernova that had appeared in Virgo's NGC 4424, SN 2012cg. I sent Celeste that-a-way, though I wasn't sure what I'd see, if anything. I hadn't thought to print a finder chart for the SN, and in fact only remembered it because a buddy mentioned it earlier in the evening. Sometimes supernovae are easy to see, other times it's hard to distinguish them from field stars without a chart. The nice recent one in M95 being an example of that. Turned out cg stood out like a sore thumb near the galaxy's nucleus as you can see in my 15-second image here.

11 p.m. had come and gone and I was still feeling pretty good. The Monster had fired me up, and the gear—camera, mount, scope—was not missing a beat. As I’d thought I would, I had plug the DVD player into the jumpstart battery after a couple of hours, but that was the only equipment hiccup. There was one bummer, though. The night started off on the dry side. With the accumulating clouds, though, heavy dew began to fall and Celeste’s tube was soon coated in the wet stuff. So what? The DewBuster kept her corrector bone dry, didn’t it? Well, yeah, but nothing saps your endurance like dew. I felt wet and clammy. The Monster had helped, and chugging a bottle of water helped some more, but not enough.

One of the reasons I am able to keep going all night, or at least till three or a little later, which Unk now considers an “all nighter,” at Chiefland is that when I am doing video there I stay under cover, under a tent canopy. Staying out of the damp lets me go a lot longer than if I am out in the open as on the PSAS dark site field.

Still, I pressed on till about midnight. By then, I’d covered most of the remaining Virgo galaxies I needed, and thought I’d do some eye-candy before our normal dark-site “turn into a pumpkin time” of 12:30 – 1:00. Beyond seeing some pretty things, I’m still learning the Mallincam, and fiddling around with its settings on bright and colorful objects is helping me improve my technique.

Alright, showpieces then. Where first? How about the Flying Saucer, NGC 4565, over in Coma? I entered them numbers into the hand paddle and the CG5 put the galaxy almost dead center in Celeste’s field. The long, thin Sb spiral with its distinctive dust lane was so nice I couldn’t resist upping the exposure from 15 to 28 seconds. I could see more details with the longer exposure, but the sky background looked a lot better at 15-seconds, no doubt due to the light-pollution-spreading humidity we were now experiencing.

After I finished with The Saucer, I happened to turn southeast and noticed Sagittarius' teapot was well up with the Milky Way’s steam pouring out of its spout. I couldn’t resist heading to summer’s premier nebula, M8, the Lagoon. When the CG5 completed the long slew from the north to the south and stopped, M8 appeared right smack in the center of the display, perfectly framed and so bright that patches seemed overexposed at 15 seconds.

Last one before Big Switch time? I wrote about M17 not long ago and was curious to see what The Swan would look like with the Mallincam Xtreme. Answer? Even at a mere 15-seconds, an almost overwhelming amount of detail was visible, including lots of outlying nebulosity, so much that if I’d upped the exposure to 28-seconds The Swan would have begun to lose his shape. I didn’t, though. M17 was still down in the Possum Swamp light dome garbage and at 15-seconds I was seeing plenty of nebulosity against a reasonably dark background.

M17 recorded, I pulled that fricking-fracking Big Switch. It was after 12:30 and equipment loading would take at least half an hour at my leisurely pace (no UFOnauts, Skunk Apes, or Bigfoots to spur me on on this night). I must have been extra leisurely in my equipment tear-down, since when I looked at Miss Lucille Van Pelt's dashboard clock as I was pulling off the field, it said it was 1:30 in the a.m. And no, I didn’t have an incident of MISSING TIME, wise guys!

Back at Chaos Manor South I did nothing more than unload the 4Runner and put the batteries on charge. I was anxious to look at the DVR’s recordings, but figgered I’d better wait till morning to do much of that. I did play the Lagoon sequence to at least assure myself the StarShoot had recorded something. From what little my bleary eyes could tell looking at the wee screen, it had done a dang good job. Finished off what was left of my Saturday night (Sunday morning, now) with a couple of brewskies and a few minutes of—guess what?—those uber-silly Ghost Adventures on the cable TV.

Next morning, but not early the next morning, I was up and had the StarShoot hooked to the DVD recorder. After a couple of false starts, I got the Night 34 video preserved on a DVD and trotted downstairs with it to see how it looked on me and D’s new LG TV. It looked stupendous. Almost as good as the video I’ve done direct to DVD. Maybe a little more in the way of compression artifacts in the background, but if I hadn't known what I was looking at I wouldn't have been able to tell the diff. If you want even better quality, you can  hook the StarShoot to a computer via the included USB cable and download/view/process digital files in their original form.

And so the Herschel 2500 is running out, muchachos. Which might bring the question, “What’s poor old Unk a-gonna do with himself after The Project is done?” The answer is that when the last object is in the can, shortly, that will still not bring the immediate end of The Herschel Project.

If The Project evolves into a book someday, which it might, I will need pictures. I’ve got some OK stills taken from my video, but some of the earlier Stellacam 2 shots are kinda yucky. I also want to do some drawings. And some DSLR (and maybe even CCD) pictures of the more photogenic objects. So, look for Unk to do another run through the H400, at least, focused on imaging and sketching following the end of the 2500.

Uncle Rod News of Note:  If you are a fan of The Herschel Project, you’ll be pleased to know it has gone big-time. The August issue of Sky and Telescope includes my article about my long-running quixotic quest!

Next Time:  Rocket City Redux…


Sunday, June 17, 2012

 

Woodstock vs. Yoda: The Thrilla in Possum Swamp


I love the StarBlast, Orion’s (Synta’s) 4-inch f/4 mini Dobsonian reflector. It is easier to get outside for spur of the moment looks at the night sky than any other telescope I own. But it’s not perfect, muchachos. It has to be collimated every once in a while, and it has a major drawback even—or maybe especially—for my uber-casual observing: cool down.

My grab and go scope, which is supplemented by an humble but loveable pair of Burgess 15x70 binoculars, is not used for complicated and challenging observing projects, but it does need to be able to present a passable image of a planet, since that’s what I usually use it for, a casual look at Jupiter, Mars, Saturn, or the Moon. And it’s got to be able to do that quick like a bunny.

Most of the time I am taking the scope from the warm house into the cold (for us) outside or from the cool house to the hot outside. It takes the StarBlast’s mirror a while to acclimate before it can begin delivering the good images it is capable of delivering. Even its wee 4-inch primary can take half an hour under the worst conditions, and that does not fit into the spirit of Chaos Manor South Guerilla Astronomy.

If I decide I want to take a look at old Jupe during a commercial while I’m watching Doomsday Preppers, I want to be able to do just that. I don’t want to haul the scope outside and wait for it to behave. I could put the StarBlast on the porch ahead of time, but I don’t usually plan my homebound observing in advance—not hardly.

I had a partial solution, I thought, Eloise, my SkyWatcher 80mm f/11 achromat, which I received “free” when I bought the Synta/SkyWatcher AZ4 mount. Eloise is pretty good optically, surprisingly good as a matter of fact.  Being a refractor, she’s ready to go with zero cool down. But, like the StarBlast, she is not perfect; that long tube has proven to be an annoyance bordering on a problem. When I want to take a 2-minute peep at The Ringed One from the front porch, it’s a pain maneuvering her out the door on her mount.

“OK, then,” Unk ruminated, “How about Woodstock?” My Short Tube 80 refractor, that is, whose coming to Chaos Manor South a dozen years ago was documented here. The 80 was my original grab ‘n goer and I loved the little telescope. But Yoda, the StarBlast, had more aperture and didn’t need a fussy GEM mount, and soon superseded if not obsoleted Woodstock. I continued to use the little feller for various tasks like Solar observing and guiding, but with the dearth of Sunspots over the last several years, and my acquisition of one of Orion’s cool 50mm guide scopes, poor Woodstock hadn’t been out of his case in…  A year? Longer?

I was thinking the grab ‘n go sitchy-ation over the other afternoon when I ran across the small box that contains my 3-inch Thousand Oaks (white light) Solar filter, the one I used with Woodstock to take peeps at Sol during the last Solar Cycle, and which I continued to use on Eloise when she came to the Old Manse. Took a look at spaceweather.com, “Hmm…nice sunspot group has come back around. Why not have a look at it? Why not have a look at it with the Short Tube 80 to see how that silly little bird compares to the longer 80?”

Since I didn’t want to fool with the EQ-2 GEM, I thought I’d see if I could mount Woodstock on the AZ-4 mount. Ought to be easy enough to waltz the alt-az rig out the door, even with its legs extended, with a shorter tube telescope riding on it. I’d already been cogitating on how to mount the Short Tube 80 on the AZ4, and in two shakes of a lamb’s tail, Woodstock was perched on the mount. The Short Tube came with a ¼-20 mounting bracket onto which you can bolt the tube rings that normally go on the scope’s EQ-1 German mount. I did that and screwed a Vixen compatible dovetail onto the mounting bracket with a ¼-20 bolt.

It was indeed easy to get the little 80 out of the house and onto the front porch without doing major damage to furniture or telescope.  I soon had the Solar filter in place and was checking out the Sun with a 12mm Plössl. Not bad. Not bad at all. Sharp, with the most prominent sunspot showing not just its dark bb-like umbra, but a fairly extensive penumbra too. All well and good. How would the 80mm f/5 compare to the 80mm f/11?

I switched out Woodstock for Eloise, attached the filter, and inserted a 26mm ocular, which would yield a comparable magnification to that of the Short Tube 80. “Hmm…lots of smaller spots I didn’t notice with the ST80.” Back on the mount went the 80. Focusing more carefully—focus is much shallower with a fast scope—brought out most of the spots I’d seen with the f/11. I still thought the image in the higher focal ratio scope was sharper, but maybe it was only a little sharper.

Might it be time to let Woodstock take up his long-lost duties as Chaos Manor South’s official grab ‘n go scope again? Perhaps. But the StarBlast, Yoda, wouldn’t go down without a fight. Years back, shortly after the StarBlast arrived, I’d had a shootout between him and the Short Tube 80 in Chaos Manor South’s backyard. It looked like it was time for a rematch.

The Contendas:

In this corner, we have Woodstock, the Synta Short Tube 80 achromat, riding on a single-arm Synta AZ4 alt-azimuth mount. Woodstock has not been in the ring in a while, but is still in fighting trim, with clean optics and a focuser that—I was surprised to note—is still smooth and easy after years of disuse. His aperture is 80mm and his focal ratio is f/5. On his tube is a minimalist but surprisingly good 30mm finder.

In the other corner is Yoda, a Synta StarBlast Newtonian reflector weighing in at 114mm of aperture. His mount is a smooth and very functional single-arm Dobsonian that features an adjustable tension, ball-bearing race-equipped altitude axis and Teflon-on-Formica bearings for azimuth. His finder is one of Orion’s ubiquitous (and overpriced) “EZ Finder II” red dot jobs.

The Eyepieces:

Both telescopes have 1.25-inch focusers, and the Short Tube 80 is equipped with a star diagonal, of course. Any number of eyepieces could have been used for this shootout, up to and including my 1.25-inch capable TeleVue 8mm and 13mm Ethoses, but I thought the 20, 15, 9, and 6mm Orion Expanse 66-degree AFOV eyepieces were more in keeping with the simple, inexpensive nature of the contestants. For lower powers, I used a classic Celestron Silver-top Plössl of 26mm focal length. When higher powers were called for, a 2x Orion Shorty Barlow and a 3x Knight Owl ED Barlow were used with the Expanses as necessary.

The place to test the mettle of the telescopes was obviously Mars, which was just past opposition at the time of the bout. It’s a challenge for any scope, since it is small even at its closest and most of its features are of a distinctly low contrast nature. I’d been rather impressed by how well the StarBlast had done on it a week or two previous, and wondered if the Short Tube 80 could possibly keep up. I did recall I had some excellent views of Jupiter when Woodstock was new. I’d seen the disk of Io transiting Jupe’s face—the disk, not just the shadow—so I wasn’t ready to count him out. While waiting for The Angry One to clear the trees, I sent both telescopes to the Moon.

Round 1

26mm Plössl  = 15x in Short Tube, 17x in StarBlast

I started out at low power, if not at the lowest power I could have mustered—I’ve got a 40mm Plössl around here somewheres. One of the major attractions of these two richest-field-telescopes is, after all, their extremely low power, wide field capability, and I wanted to give both a chance to show that off.

Short Tube 80:  What a lovely image of a nice, gibbous Moon! Framed by a huge expanse of sky and the chimney top of the house next door, it was just exquisite. The terminator was dead sharp. “But how about the COLOR, Unk? How about the dreaded color purple?” Chromatic aberration is always the 64 dollar question when talking “achromat,” especially “fast achromat,” ain’t it? There was some color, but it wasn’t purple. With my eye on axis, there was a fairly subdued amber fringe along the limb. Placing my eye off axis, it took on a purple hue, but was not at all disturbing.

If you are going to have a fast optical system, which is what most of us want in a grab ‘n go, you are likely gonna have some field curvature and/or coma. How was Woodstock? Moving the Moon around in the field, I found the image was pretty sharp in the simple-design eyepiece till about 70% of the way to the field stop. Even past there it was OK, if not razor sharp.

StarBlast:  The eyepiece delivered slightly higher power in the StarBlast, but in most ways the image was identical to what I’d seen in the refractor. Good and sharp. Excess color? There was none. And I don’t just mean there was no amber or purple stripe along the limb, but that the whole disk of the Moon looked truer in color. In the Short Tube, the Moon had a slight but noticeable yellowish tint, but in the StarBlast it was a pure, silvery hue that just looked more natural and “better” in comparison.

On the other hand, the coma inherent in a fast reflector assured that the refractor pulled ahead in the edge-of-field department. In the StarBlast, the image began to go mushy about 50% of the way from the center of the field, and at the edge it was rather icky indeed. I also noticed the fairly obvious shadow of the StarBlast’s secondary mirror with this bright target at such low power.

Woodstock was victorious in Round 1. Despite the reflector’s lack of color, the refractor took the laurels due to its flatter field and lack of a secondary shadow.

Round 2

15mm Expanse = 27x in Short Tube 80, 30x in StarBlast

At 27x, the image of the Moon delivered by the Short Tube was still amazingly sharp. The higher magnification began to bring out details, too, like the terracing of the walls of the great crater Copernicus. Chromatic aberration? No more than what was seen at 15x.

The 30x image in the StarBlast was unmistakably brighter than the 27x image in the refractor. Otherwise? The level of detail visible on the terminator was about the same as that in the Short Tube 80. Once again, the color appeared more natural in the reflector than in the refractor. I only tended to notice that when I moved back and forth between the telescopes, though.

Round Two was judged to be a tie…

Round 3

9mm Expanse = 44x in Short Tube 80, 50x in StarBlast

At 40x, a good scanning/casual observing power, the refractor was still delivering the goods—and how. The terminator was an amazing welter of tiny details, with Gassendi, where the Sun was just rising, looking impressively sharp. How about areas of the disk away from the terminator? Looking good. The maria stood out with decent contrast. Unfortunately, chromatic aberration was becoming more obvious. Color fringing on the limb was harder to ignore, and I thought I detected a hint of purple in the shadows of the terminator detail. Not crazy bad, but there.

Yoda laughed. This is where the StarBlast began to pull ahead. Not only was the absence of spurious color immediately obvious, the terminator detail was good and sharp. It was sharp in the refractor, but it was just a little sharper in the reflector. I also noted that the detail on the disk away from the terminator, Tycho’s ray system for example, was higher in contrast and easier to see in the StarBlast.

Round Three went to Yoda, but just barely…

Round Four

6mm Expanse = 66x in Short Tube 80, 76x in StarBlast

Kicking up the power a notch delivered more detail with Woodstock. Small detail, like the craterlets that litter the floor of Clavius, popped right into view. I liked the look of it a lot. Alas, away from the day-night line, the disk was looking decidedly soft. Not bad, mind you, but not quite as sharp as at lower power.

At 76x, the level of detail visible with Yoda was impressive. Copernicus, with his complex central peak and fascinating walls, was just nuts. The arc of small craters in Clavius was visible in the refractor, but it was sharper in the reflector, and I was able to see some smaller features on the crater floor that were not apparent in the ST80. The disk away from the terminator looked every bit as good as it did at lower power—much better than in the Short Tube, in other words.

Round Four was given to Yoda, and it wasn’t even close…

Round five

6mm Expanse, 2x Barlow = 133x in Short Tube 80, 152x in StarBlast

Little Woodstock was still on his feet, but was looking wobbly. The Short Tube 80’s image, including the terminator, was getting undeniably soft. Surprisingly, chromatic aberration, though certainly noticeable, didn’t look much worse than it had at 66x. Despite the slight softening, there was plenty of detail to be seen. Gassendi was looking very complex. Offsetting that, the image was now also on the dim side.

Yoda? At this magnification, Luna in the StarBlast reminded me very much of the way it looked back in the day in my long focal length Palomar Junior 4.25-inch reflector. Tons of detail on view everywhere and as sharp as ever.

Round Five was Yoda again, and, again, not even close…

Round Six

6mm Expanse, 3x Knight Owl Barlow = 200x in Short Tube, 228x in StarBlast

If Woodstock was wobbling before, he was stumbling now. The Moon’s image was soft overall, softer than ever, and I wasn’t seeing any more detail than I had at lower power. Surprisingly, color was still under control. 200x was somewhat useable, and might have been a wee bit better with better seeing, but it was a lot to ask of this f/5 achromat.

Yoda laughed again. He took on 228x without complaint and seemed ready for more. The image was getting dimmer—this is a 4-inch telescope—but it was still astoundingly sharp. The bright spot on the floor of Plato that marks the most prominent of his craterlets winked right into view. Gassendi was superb and so was Clavius, and I was definitely seeing more detail than I had at lower power.

Round Six was another victory for Yoda. The referee considered stopping the fight, but Woodstock begged to be allowed to go on…to Mars…

Round Seven

Due to the depredations of clouds, Mars had to wait till the next night. When Barsoom put in his appearance, it didn’t take long to determine what was what. Let’s make this short and sweet: The Angry Red Planet laid Woodstock out on the canvas. At about 100x, the image was pretty good, but that was far too little magnification to do more than just show the bright red “star” was indeed Mars. Pumping it up to 200x, just enough magnification to reveal details, made the disk of Mars a mess. No combination of eyepieces or Barlows helped. The small refractor was well and truly done.

So the victor was the StarBlast? Sorta. Yoda disappointed a little bit. Yes, at 200x, the image was much cleaner than in the 80. I could see the polar cap, and I could see hints of dark features, but it was clear the scope needed at least a little while to adjust to outdoor temps. The image was good, just not as good as I knew it could be in this amazing little scope.

The real and surprise winner, I guess, was the 80mm f/11 refractor. On a whim, I hauled her out, and Eloise produced simply outstanding images given her aperture. Even at 300x, Mars was a good-looking ball showing fleeting surface detail and a polar cap. I suppose the contest had morphed from a prizefight into a horserace with the 80mm f/11 coming from behind to best the StarBlast by a nose.

So what now? Status quo. The idea of resurrecting the Short Tube 80 was a good one, and I suppose he could do alright once in a while, for a casual look at the Moon, maybe. But there is no denying he is the weakest of the three telescopes. I reckon Yoda will remain the primary g ‘n g scope at Chaos Manor South. But when I need top-notch images in a hurry without cool down, I’ll just have to wrestle the 80 f/11 out the front door.

I’m not sure there is a perfect grab ‘n go for me. It would have to be something like a short and light 4 – 5-inch APO refractor, and even if I found one short enough and light enough to serve, I probably wouldn’t want to pay for it. If I ever do achieve grab and go nirvana, I guar-ron-tee y’all will be the first to know about it, muchachos.

Next Time: The Herschel Project Night 34…



Sunday, June 10, 2012

 

Me and Mr. Sun



The Venus transit! Last chance to see lovely Aphrodite cross the face of the Sun in our lifetimes, muchachos. Naturally Unk wanted to catch it, and naturally he prepared for it in his usual haphazard and confused fashion. “Got to go to the shipyard in New Orleans Tuesday. I’ll leave by noon and be home in time to pick up Miss Dorothy and head for somewhere where we can get a good view.” "Plan" in place, I loaded up the short tube 80 and its little GEM in the 4Runner and lit out for Avondale, Louisiana.

I was back home by 2 p.m., and with a little time to kill I fired up the Internet on Chaos Manor South’s kitchen workstation. “Well, that’s funny. Thought there’d be more folks talking about the Transit. Huh! Guess I’ll get the exact time of first contact for us with Cartes du Ciel. Why is Venus so far away from the Sun? What’s wrong with Cartes? Wait…Dorothy, honey, what’s today’s date?

Yep, Unk was preparing to head out for the Venus transit exactly one week early. I was abashed, but at least Miss D. and I had a good laugh over it. In my defense, I’ve been awful busy lately, and the Transit and finding a way to squeeze it into my schedule has been much on my mind such as it is. Having an extra week did allow me to get my ducks in a more orderly row, starting with the telescope. Now that I had time to think about it, I decided I wanted to watch Venus with something better than the dadgum Short Tube 80—but what?

And where should we observe from? My friend, former student, and Possum Swamp Astronomical Society Vice President, Jonathan, thought the best place for the club to set up would be Fairhope pier on Mobile Bay, on the eastern shore of Mobile Bay. Since this would be a sunset transit, we’d have an unobstructed view to the west over the water.

Well, we'd have an unobstructed view if it wasn’t obstructed by clouds. The weather reports on Monday the fourth were not encouraging. We went from “scattered thunderstorms possible” to “thunderstorms with possible severe weather.” Ain't that always the way it always is for any astronomy “spectacular”? I went to bed Monday night with few hopes but resolved to head out to Fairhope as long as it wasn't pouring down rain.

Before I tell y’all how the big day turned out, maybe a few remarks about Unk’s relationship with Mr. Sun are appropriate. It’s been an off again – on again friendship, y’all. As a sprout I was fascinated with the idea of seeing sunspots, but I was afraid to look at ‘em. The stern and heartfelt warnings against viewing the Sun with a telescope my mentor, Patrick Moore, put in his books dang sure dissuaded me. If Mr. Moore said “no,” it was “no.”

Still, I was semi-tempted when I got my first telescope, a 3-inch Tasco reflector. Like most of the Japanese telescopes of the day, it came with a Sun filter. An eyepiece Sun filter. Such a thing is inherently dangerous, since it’s screwed on to the ocular near prime focus. It doesn’t take long for one to overheat and crack, possibly and disastrously while you are using it. I knew that from Patrick’s writings, but was still tempted. Tasco wouldn’t give me something that was dangerous, would they?

Luckily, I suppose, Daddy, who was almost as big a fan of Patrick Moore as I was, spotted the Sun filter in the little scope’s box and took possession of it immediately. We did both take a brief look at the Sun with it late one afternoon, and I do mean brief, maybe three seconds, with daddy slewing the scope off the Sun between his look and mine to allow the filter to cool. In retrospect, there probably wasn’t much danger with three inches of aperture, but following our peeps at Sol, daddy wisely took a nail and hammer to the filter and that was the end of it.

What had I seen during the brief peek Daddy allowed? Not much, but what little I did see, the orange and featureless limb of the Sun, was somehow fascinating, and that quick look is still clear in my mind’s eye. I won’t say I became obsessed with the Sun, but I was interested, anyway.

I did a series of crayon drawings of my view enhanced by what I imagined sunspots would look like, and the corona I saw in the pictures of the Sun in Stars. My little girlfriend, Jitter Jones, was puzzled by my Sun’s colorful corona, saying it looked like the collar on Bozo the Clown’s costume—we watched his show every afternoon—but was also quick to add that my much labored over-masterpieces were “great.”

I didn’t get my next view of ol’ Sol till two years later, the second summer I had my Palomar Junior. I’d finally saved enough money for Edmund's camera mount so I could advance my program of taking Moon pictures with my Argus box camera. Well, I hadn’t really saved. I’d got a crisp five-dollar bill from my generous Aunt Lulu, and that, combined with a couple of dollars here and there from other relatives and a buck kicked in by the Old Man, was just enough to cover the cost of the afocal camera rig.

When it arrived, I was surprised to find a square of white-painted metal in the box. According to the instructions, you mounted that on the bracket in lieu of a camera and projected the Sun’s image on it. I got the idea, and was soon ready to give it a try. Everybody, even Patrick Moore, had to admit viewing the Sun by means of eyepiece projection was completely safe.

I knew not to look through the finder, and when I’d dragged the Pal Junior out onto the blacktop behind the carport, the area the OM called “the turnround,” I aimed it by pointing roughly at the day-star and moving the scope till its shadow was as small as I could get it. When it was, a sharp, clear, and bright image flashed onto the screen.

What did I see? I was lucky to be observing the Sun in 1967, two years from a Solar cycle maximum, and our star’s face was freckled with intricate sunspot groups. A little experimentation showed I could leave the 25mm Kellner in the scope and enlarge the images by sliding my projection screen farther from the eyepiece. I could zoom in on small areas of the disk that-a-way and get a clearer view than I got by switching to my pitiful 12mm Ramsden.

I very much enjoyed the Solar cycle that peaked in 1969. The finale came one summer afternoon that year. The OM was working on his latest project, a homebrew radio transceiver, and not just any transceiver, but a high-tech single-sideband transceiver. I had a brand spanking new “ticket,” a ham radio license, and liked to watch daddy work on his bench in the carport. His ham rigs lived in our Utility room till summer heat chased him out into the carport, and, finally, into the house despite Mama’s protests.

The Sun was fierce that afternoon in a way he can only be in Gulf Coast summer. Which impelled me to become curious as to what was going on with him. It had been a couple of weeks since I’d had a look. I got my Pal into the carport and assembled and was preparing to lug him onto the turnaround when I had an epiphany: the Sun was low enough that I could set the scope up in the carport and observe from in there, sharing the fan the Old Man had pointed at him. It was then that I got another idea. I wouldn’t need my sun projection screen; I could project Sol on the ceiling of the carport.

Which is exactly what I did. The Kellner threw a 3-foot wide Sun on the ceiling, and it was clear and incredibly detailed. Not only could I see sunspots with their lacy coronas, the granulation of the Sun's disk was clear. I yelled for the OM to come over, and we stood and stared for a long time. Too long. All of a sudden, the image dimmed as if a cloud had covered the Sun’s face. I poked my head outside. Nope. Not a cloud in sight. I had a sinking feeling and pulled the Kellner out of the focuser to check it.

The eyepiece’s formerly clear optics were cloudy. I asked the OM “What the hell?” So upset was young Unk that he actually uttered that profanity. Dang good thing Mama wasn’t within earshot. Daddy pretended he hadn’t heard the aitch word, "Well, it looks like the heat of the Sun didn’t do much for the Canada balsam.” Back in them days the elements of eyepieces were often glued together with what was in essence tree sap. The Sun’s heat had made this “glue” cloudy.

I was broken hearted since this was my best and lowest power eyepiece. OM to the rescue. He disassembled it. The heat had made the balsam lose its adhesive properties,so he was able to separate the two lens elements easily, clean them off, and put them back together without glue.

To be honest, the simple eyepiece worked as well (or as poorly) as it ever had, but I was devastated. After that, I didn’t turn a scope to the Sun again for years. I could have dedicated the now balsamless eyepiece to Solar use, but I was convinced, subconsciously anyway, that if I pointed a scope at the Sun again something bad was sure to happen. Patrick Moore was right after all.

The total solar eclipse of 1970 was all but clouded out for our part of the country, so I didn't have to worry about ruining another eyepiece to observe it. I had formulated a somewhat nebulous plan that involved me driving my decrepit 1962 Ford Galaxie across the panhandle of Florida to the path of totality (it passed not far from the spot where the Chiefland Astronomy Village lies today). Weather reports a day or two prior to the event made it pretty clear I’d be wasting my time, and the OM was eventually able to talk some sense into me: “Go ahead and go, but you won’t see a thing and I won’t be happy when I have to take off work and come rescue you when that Ford leaves you by the side of the road.”

I eventually got over my phobia and used projection to view a couple of partial solar eclipses in the 80s. That was about it, though. I’d sometimes resolve to spend more time with the Sun, monitoring and drawing his disk, but that would usually only last a day or two and I’d be back to spending the late afternoons watching Thundercats and Voltron: Defender of the Universe.

Since then? I've kept my hand in and maybe even kicked my Solar work up a notch or three.That began when I got my Short Tube 80 and on a whim one boring afternoon at a star party purchased a Thousand Oaks Solar filter for it. Even better was the excellent JMB full-aperture filter I got for my C8s a few years back, which made the detail I remembered from the Pal Junior’s images seem puny. Or would have if we hadn’t been at the bottom of a cycle. The biggest events in recent times Sun-wise? The Christmas partial eclipse of 2000 and, way bigger, the Venus transit of June 2004.

Transits of Venus, Venus crossing the disk of the Sun, are among the rarest of predictable astronomical events, occurring in pairs eight years apart and separated by gaps of either 121.5 or 105.5 years. You can dang sure bet my buddy Pat and I intended to see Venus’ dark spot cross Sol in 2004.

That year the event took place at sunrise, and the best place we found to observe it was on the Causeway across Mobile Bay, at Battleship Park. How was it? It was stupendous. We were troubled only a little by clouds, and our telescopes, my Short Tube 80 and Pat’s filtered Astroscan optics-based Newtonian reflector, did a good job even if Venus was a little small in them.

I talked to Pat shortly before last week’s second and final (for us) Transit. I told him I didn't have high hopes for the weather, but that that was OK. We’d seen the first one, and 2012 would just be the icing on the cake. That’s what I said, but deep down, I wanted to see Venus cross the Sun again. That always smoldering ember of interest in our star was threatening to burst into flame inside me again.

On the day of the event, I’d—wouldn’t you guess it—been called to New Orleans again. But just as on the day of my false start the previous week, I’d got out of there by mid-morning and was back at Chaos Manor South by 1330. I relaxed for a while, checking Cartes for the start of the event at Fairhope’s longitude. Looked like First Contact would be at about 1710, so me and Miss D. would need to leave around 1600.

At 1530 I loaded up the telescope and the other gear. This time I left the Short Tube 80 at home. I coulda taken a C8, but given the poor conditions—looked like the wind was gonna be kicking up and the seeing might be kinda punk—I demurred. The Sun + poor seeing + public viewing + possible threatening weather = long focus refractor. My 80mm f/11 Sky-Watcher, Eloise, ought to be perfect, and the Short Tube’s Thousand Oaks filter fits her perfectly.

Other stuff?The small eyepiece box, the one loaded with Plössls and Orion’s Expanse oculars. The relatively long focal length Eloise is very forgiving of simple eyepieces. The solar filter, of course. And that was it. I didn’t even pack my small observing table. I guessed there would be picnic table somewhere in the area that would serve.

The sky did not look great. It did not look good. It was barely fair, but Miss D. and I headed east at 4 p.m. nevertheless. Arriving at the pier, we were blown away. Literally. When we stepped out of the 4Runner the hats we brought to protect us from the June Sun—if there was any Sun—immediately tried to fly away. I estimated the wind was gusting up to 25 knots at least. Hell, normally placid Mobile Bay was white-capping. We held onto our hats, and since we didn’t see any of our buddies in or near the parking lot, we walked out onto the long pier.

Besides the high winds, one other disappointment was that the restaurant on the pier, Yardarm’s, where I'd hoped me and D. could have supper after the Transit, was closed. Ah, well. We didn’t see our friends on the pier, and it was way too windy think about setting up there. Heading back to land, we found Jonathan and company had set up in a nice grassy and somewhat protected area just east of the wharf. The wind was still a nuisance, but trees and bushes made it a tolerable nuisance.

I noted several members of the public were already hanging out in the area. We hadn't made a big deal of our Transit star party, but one of our longtime members who is on the staff of the local paper had got the word out. I have no doubt we probably would have hosted hundreds instead of tens of kids and adults if the weather had been better, but lower numbers made this a more fun and less stressful event for all concerned.

Miss Dorothy and I set up the refractor and waited, not just for Venus to begin her crossing, but for the Sun to escape the clouds. At 1630 he was completely invisible. An amateur astronomer’s hope springs eternal of course, and is sometimes rewarded. Just before the Transit was to began, sucker holes began to appear, and we were soon seeing a small “bite” out of Sol in Eloise, who offered a sharp and detailed image of the Sun, his spots, and Venus. This was a refractor day, and the 3-inch did as fine a job as I could have wanted.

I let our guests have a good look at the bite, but monopolized the scope for a few minutes as Venus’ disk began to move onto the Sun, directing our excited visitors to Jonathan’s 4.5-inch Dob-newt reflector and his Coronado hydrogen-alpha refractor.I wanted, above all, to see if I could detect the still somewhat mysterious “black drop”effect.

What’s that? Just as Venus is about to move completely onto the disk of the Sun, just before "second contact,” that is, a small black “teardrop” appears to connect the disk of the planet and the limb of the Sun. This “stretching out” of the planet makes it impossible to accurately time Second Contact, and used to be attributed to the planet’s thick atmosphere. These days it is thought to be nothing more than an optical illusion.

Optical illusion or no, I wanted to see it, and given the excellent images Eloise was delivering I was purty sure I would. Compared to what it was like in the Short Tube 80, Venus seemed huge in a 20mm expanse eyepiece. Sure enough, just as it pulled away from the limb, the black dot of Venus was stretched out and remained “connected” to the limb. Just as my brain processed the fact that I was actually seeing this legendary phenomenon, howsomeever, the Sun dimmed and went out. More incoming clouds, dagnabbit. I’d seen the black drop, but just barely.

We and our guests cooled our heels for a little while, but the Sun was back fairly soon,and kids and adults could just not get enough of him. One and all were amazed at how easy Venus was to see and how much it looked like the “preview” pictures CNN and Fox had been showing Monday evening. In addition to the scopes, we handed out some of the now-ubiquitous “solar-glasses,” cardboard glasses with Solar filter material for lenses. These are perfectly safe to use, but I opined that Venus would probably be too small to see with the naked eye. Miss Dorothy proved me wrong shortly, announcing she could see the planet easily.

And so it went for 45-minutes. Unk even managed to get a couple of pictures of the event by the simple means of holding his iPhone camera up to the eyepiece. I knew we would not see the entire event—the Sun would set for our longitude well before the end—but I’d hoped for a little more than we got. Just before six, thunder began to rumble. I walked out to the parking lot and had a look to the north. More clouds. Black clouds. Moving our way. Lightning bolts. I made my way back to the scopes and told Dorothy and Jonathan that it was about time to pack it in. they agreed. The hot sun, when it was out, and the constant wind conspired to spell h-a-v-e h-a-d e-n-o-u-g-h for us, anyway.

Miss D. and I had Eloise back in the truck in one quick trip and had just pulled out of the parking lot when it began to sprinkle. Not long after that, right before we got back to Highway 98, the bottom fell out with torrential rain and high winds.Talk about good timing. On the way home we stopped at Tacky Jack’s on the Causeway for some seafood for me and D., some “sarsaparillas” for Unk, and a little note-comparing. We’d had a great time, seen plenty of the transit if not as much as we’d have liked, Eloise had done well, and the public had been overjoyed with the big show. What more can you ask?

So where does that leave me and Mr. Sun, muchachos? I intend to get Eloise out into the front yard and have a look at the Sun more often. Will I follow through on that? We’ll see. Pat has just returned from this year’s RTMC Expo (née “Riverside Telescope Makers’ Conference”), and he tells me he was bowled over by Lunt's new and (relatively) inexpensive 35mm hydrogen-alpha telescope. Hmm… If I had an h-a scope, that might really spur my Solar observing. On the other hand, Unk, as you know, is a cheapskate so we will see.

Next Time: The Thrilla in Possum Swamp…


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