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The 8-mm Ethos Faces Dark Skies
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Which was just what I didn’t need. After a punishing summer and fall at work, I was ready for a break, and the (new) Chiefland Star Party seemed the perfect place to get one. If you’ve been hidin’ under a rock the last decade or so, the Chiefland Star Party is a great big do under dark skies near the little Florida town of Chiefland. It's an event that has in the past attracted upwards of 300 deep sky-crazed amateur astronomers. Unfortunately, this much-loved venue had rapidly outgrown its facilities. There was no longer enough room for talks, vendors, porta-potties, or telescopes. For that reason, the CSP took a couple of years off. For a while it looked like that "couple of years” might become "forever.” But the CSP was just too good to let it ride off into the Sunset, and it was to be back this fall with plenty of electricity, a more enclosed area for vendors, a better place to hold talks (than the old open-air pavilion) and, most of all, a new and much larger observing field. I was countin’ the days to 24 October and the beginning of Chiefland 08, especially since I had an agenda.
Agenda? Yep, spelled "E-t-h-o-s.” I sprang for the 13mm uber eyepiece several months ago, and dug way down deep for the 8mm a few weeks back, but had not yet had the opportunity to get either of them out to a dark site or, thanks to Gulf Coast summer clouds, storms, and HURRICANES, even do much at our semi-dark club site. The limited observing I’d been able to do from our compromised skies indicated the Ethoses were indeed amazing. Maybe even astounding. But I couldn’t put the final nail in the coffin of 82 degree apparent field oculars until I could try these 100 degree AFOV puppies out somewhere where the Milky Way don’t just shine, but blazes. Suddenly it looked as if that might not happen, at least not in the limited amount of time I’d be Down Chiefland Way. Due to my always koo-koo schedule, I planned to arrive on the Wednesday prior to the star party (I am a Chiefland club member, so that would be permissible) and stay through only the first weekend of this week-long event.
When I went to bed Tuesday night, it wasn’t lookin’ good. "Partly cloudy tonight” forecasts had been modified to "GOOD chance of thunderstorms all evening” for two of the four nights I would be in onsite. Nevertheless, the next mornin’ I packed the Toyota and headed south. I’ve always had a great time at CAV—rain or shine. What did I take with me in addition to my two pretty babies? The scope would be my time honored 12.5-inch truss tube Dobsonian "Dobbie” (yeah, creative, I know), who’s proved his mettle over 15 observing seasons. Why him instead of one o’ my CATs? I love my SCTs, sure, but nothing makes for a more impressive visual experience than the wide fields of a fast (Dobbie’s an f/4.8) Newtonian. I will also admit to y’all that after working on my forthcoming book, Choosing and Using a New CAT (November), for nearly two years I was ready for a short break from SCTs, much as I love ‘em.
The drive down was uneventful and was made more pleasant by my iPod, which I’d loaded up with an audio book, Walter Isaacson’s Einstein: His Life and Universe. The way gas prices have fallen didn’t hurt my digestion neither. Best of all, the farther south I went, the better the skies looked. When I’d left Possum Swamp, clouds had definitely begun movin’ in, but by the time I passed Tallahassee the skies were again cerulean. As the afternoon wore on and I got closer to my destination, I did begin to notice an increasing number of fluffy-white members of the cloud tribe. These were still relatively small and few, though, and I reassured myself that these were likely just "a few afternoon clouds off’n the Gulf.” By the time I’d checked into the Chiefland Holiday Inn Express (my usual "campsite”), and headed out to the CAV, though, it was obvious bad weather was on its way. The only question was "when."
After I’d set-up scope and EZ-up canopy and spent some time with my old friends Tom and Jeannie Clark (of Tectron Telescopes and Amateur Astronomy Magazine fame), I took a critical look at the sky. One glance and I began to lose hope for Wednesday night. More clouds, now—thick, dark suckers. But then, almost magically, they began to thin and clear. My record was unbroken. As I observed to Tom, in all the years I’ve been observing at Chiefland I have never yet been totally skunked; I have always had at least part of one evening every single trip. As the Milky Way began to glow and then burn, it was obvious this trip would be no different.
Tom and I unlimbered his fantastic 24-inch f/4.5, "Mini-Beast,” inserted the 13E, and got to work. Just as twilight ended, we thought to take a look at M22, which would soon be too low to fool with. Tom centered the big Sagittarius glob, and then squawked. Earlier, I thought I’d detected a little skepticism about the Ethoses from this Dobsonian guru, but it was clear ol’ T.C. was likin’ what he was seein’. When I pressed my eye to the 13, I was ready to be impressed, but not nearly knocked off the ladder as I was. What was before me (that seems a more apt way of describing the Ethos experience than "in the eyepiece”) was an enormous globe of tiny, tiny stars. The big old grandpappy glob literally filled that enormous field. Again, as I have said before to all who will listen, it was not just the big field that was so amazing. Oh, that was part of it, but what was CRAZY was how sharp the image was. And how high the contrast was. With M22 not much above 25 degrees, I expected mushiness, but that was most assuredly not what I got. It was crisp, it was beautiful, and the stars were deadly-sharp pinpoints despite their low-altitude.
I was, frankly, also interested to see what the Ethos would be like in a fast(er) scope like this f/4.5. As you may know, not even Nagler and Ethos eyepieces will do anything to counteract coma. To "fix” this problem of faster Newtonians, to get them edge-stars back to being pinpoints instead of comets, you need a TeleVue Paracorr (or other coma corrector). Which we didn’t use. I have heard some comments that coma seems worse with the Ethoses than with the Naglers, since the field is significantly larger. My verdict? That may be the case, but I did not find the effect pronounced or disturbing in this f/4.5. In fact, I didn’t notice much coma at all the whole time we was admiring M22. I just drank it in. When I did think to worry about the field edge, yes, it was there. Is the coma displayed in the 13 Ethos more obvious than that in a 13mm Nagler due to the 100 degrees of AFOV? Perhaps a little bit for some folks, but I didn’t find the overall coma level in the 13E more troubling than it was in Tom’s 13mm Nagler.
What else did I notice? I’m sure I’ll take some flack from the Ethos nay-sayers, but at the risk of being dubbed an "Ethos Elitist,” yes, swapping back and forth between the 13 Ethos and 13 Nagler, I was slapped in the face AFOV-wise. I ain’t a-gonna sugar-coat it for you. Going back to a "mere” Nagler was very similar to my first experience with Naglers at a late-80s star party. The Nagler ruined my Erfles and Plossls for me, and the Ethos has ruined Naglers for me. Both Tom and I commented that, alas, the wonderful Nagler spacewalk just wasn’t so wonderful no more. Some of you won’t like me sayin’ this, but there it is. You may think different or think you’ll think different, but that’s what I experienced on this night. Could I still be happy with a 13 Nagler? Sure. I guess. The Nag’s a fine eyepiece, but it would be a long time before I would be able get those mind-blowing Ethos visions outa my mind and be able to truly love a Nagler again. It wasn’t just that way with magnificent M22, either. One showpiece after another was as beautiful as the last in the 13: M13, M92, M17 and on and on.
But that was the 13mm, and I’m sure y’all are tired of hearing me gush about it. What about the 8-mm? I had to wait to find out. My first evening at Chiefland started with a depressing number of clouds in the sky, segued into a truly inspirational sky tour with Mini-Beast and the 13mm, and descended into a depressing morass of cloudy skies as the promised storm front began to push in around midnight. Didn’t I use the 8mm at all? I did, but very poor seeing ahead of the storm did not allow it to shine in the 24-inch, or even in my 12.5-inch. No, I’d wait for good weather before seriously puttin’ it through its paces. Surely I’d have the chance, as I’d be at the site until the following Sunday.
If I couldn’t look through the 8 Ethos, maybe I could look at it? This eyepiece is very much the little brother of the 13. The 8 is both slightly smaller and slightly lighter than Bubba. In other ways, it is identical. Like the 13mm, the 8mm returns to the days of the TeleVue "skirt;” it is a hybrid 1.25-inch/2-inch eyepiece. Also like the 13, the build quality of the 8 is faultless. Everything is beautifully put together. Everything that needs to be is more than sufficiently blackened to prevent uwonted reflections. That includes, judging by some "strip-down” photos of a disassembled 8mm on the Cloudy Nights website, its 9 lens elements, which have blackened edges. This one is a little less impressive than the 13: it’s shorter, and it doesn’t come in the near valise-sized box of the 13, but it is still very impressive in its quality and solidity.
As we went from clouds late Wednesday night to purty-much torrential rain early Thursday morning, to leaden skies and occasional rain Thursday night, to more of the same all day Friday and Friday night, I began to wonder whether I would get to try the 8mm at all this trip. What did I do while waiting on a predicted front passage that seemed to keep being delayed? I spent quite a few hours chattin’ with Tom and Jeannie, fellow astronomy author Steve Coe, and Amateur Astronomy Magazine’s current Publisher and Editor Charlie Warren. We had some great times, too, jawbonin’ about the amateur astronomy game old and new, but there was no denying Steve, Charlie, and I longed for clear and dark Chiefland skies. Ol’ cockeyed optimist me predicted "some viewing” Saturday night, but I was proven badly wrong and had to endure some good-natured ribbin’ along the lines of, "You brought two new Ethoses with ya? We know what attracted them clouds, then.”
Luckily for my scalp, it appeared the heavens would clear for Saturday evening, if not as quickly as we’d hoped. The cold front did not begin to move through in earnest until about 10pm Saturday, but when it did, it did, and scopes were quickly uncovered both in our area, the Clarks’ backyard and the "club field,” and on the star party observing field itself. And how about the actual, official Chiefland Star Party? I was registered, but did not spend a lot of time over there. I was having too great a time with my buddies over at the Clarks’ and the rain and drizzle did not encourage tramping across the big, new field. I did note on my couple of trips that-a-way that the good folk there seemed happy—well, as happy as amateur astronomers get under cloudy skies. The event appeared well-organized, and there were some welcome additions this year, including the presence of "Micki’s Kitchen,” the catering outfit that has been selling food at the Winter Star Party for a while. The ugly skies appeared to be keeping attendance down on Friday, but the large field had begun to fill on Saturday mornin’ as more attendees rolled-in with the promise of clear weather.
Anyhoo, by 10pm Saturday the cover was finally off ol’ Dobbie again, the Sky Commander was aligned, and I was ready to see what my other expensive glass could do. What to look at? With the sky not completely dark and a few clouds still hanging-in to the south and west, I turned to M2, the great globular cluster in Aquarius. What did I think? Beautiful. Just be-yoo-tiful. Oh, maybe not quite as cool as M22 had been in the 13 Ethos the previous evening, but, then, M2 is not the glob M22 is. As it was, the cluster was impressively resolved, with plenty of stars crisscrossing a core filled with misty light. As a test, I swapped in the 13. Nice too. Nice? Hell, "outstanding.” But I preferred the 8. In the still-bright skies, the higher magnification of the 8mm provided more contrast and more resolution. Coma? That’s minimal at best in my f/5 telescope, so I hotfooted it over to the 24-inch and gave it a try on M2 as well. Verdict? As with the 13E, the larger apparent field does make the condition of field edge stars more noticeable. As mentioned above, the Ethoses, like the Naglers, are not designed to do anything to reduce coma, and don’t.
Is the 8-mm perfect, then? No. No eyepiece is. Each is a compromise and the 8 Ethos (like the 13) is no different. Its faults? I had to look long and hard to find something to downcheck it on. I certainly didn’t notice any astigmatism. Nor could I detect any modicum of barrel distortion or "pincushioning” as I cruised rich Milky Way star fields. The only nasty negativism of note is that it is my impression than both Ethoses are prone to a bit more "blackout” effects than some of the Naglers. Don’t hold your eye in the right spot when viewing, and you do notice dark patches in the field, especially with a bright background.
In part this "problem” may be due in part to the fact that the Ethoses offer more eye relief, about 15-mm, than most ultrawides. That makes it—for me anyway—a little harder to position my eye properly. I did find leaving the eyeguard/cup up helped me get my eye in the right spot. I don’t normally use eye cups on eyepieces, but using one on the Ethos was not a problem. Even with it up, I could easily take-in all of that great, huge porthole. Now, don’t get me wrong about this: blackout is not a major problem with these oculars. Certainly they demonstrate far less than something like, say, the 35mm Panoptic (still a fave of mine, nevertheless). It’s also been my observation that it takes me a while to "learn” to use an eyepiece, and that once I do, things like eye-positioning begin to come easily and naturally.
I said I was through gushing. I lied. I can’t help it given what I saw on this Saturday night. To begin, I was casually touring the Herschel 400 using Steve O’Meara’s excellent book, Steve O'Meara's Herschel 400 Observing Guide. What really brought me up short was how much all them little galaxies scattered down through Pegasus looked like their pictures. Wanting something a little prettier than the run-o’-the-mill H400 galaxy, I punched NGC 7331, "Andromeda Junior,” into the Sky Commander. Not only was the main galaxy bright and detailed, the Deer in the Deerlick (Ask me what Steve Coe’s new nickname for this one is some time!), the little companion galaxies nearby, were as evident as I’ve ever seen them in Dobbie. Swinging over to M74, I was surprised to see this sometimes difficult spiral’s arms standing out like sore thumbs. I don’t think I’ve had as good a view of this challenging face-on spiral in the 12.5-inch since one special night at the Deep South Regional Star Gaze nearly 15 years ago. Hell, I didn’t think my eyes were still good enough to see somethin’ like this. What else?
M31 was ridin’ high, why not? 8mm may sound like a lot of magnification to use on this elephant of a galaxy, but it really is not, not if you want details instead of just the big picture. As with M74, I saw more of M31 than I’d seen in a long time. Heck, I don’t know I’ve ever had as good a view of this monster with any scope. Start with the dark lanes. Two were starkly visible. The satellite galaxies, M32 and M110? M32 nearly ruined my night vision. M110 was large—huge—and I seemed to see some sort of fleeting detail near its core. Speaking of galactic nuclei, M31’s core on this evening in the 8 was not merely "star-like,” it was a tiny blazing pinpoint. I also noticed that something I have had a lot of trouble with over the years, the galaxy’s enormous star cloud, NGC 206, was not merely "suspected” or "visible,” it was bright and easy. My only regret is that I didn’t spend some time hunting down some of M31’s horde of globular clusters when I was in the neighborhood. Next time.
So is the 8mm Ethos magic? Really, really magic? There was definitely magic in my eyepiece on this night. But was it the eyepiece or was it the excellent Chiefland skies? No doubt the good conditions in the wake of a front passage had something to do with the excellent views, but I am convinced this wonder-eyepiece deserves its share of the credit. Certainly its superior sharpness and contrast couldn’t help but aid in bringing this sufeit of marvels into view for my middle-aged eyes. The only bad thing? I had to stop way before I was ready. As often happens—to this pore ol’ boy, anyway--the best skies came on the last night (for me) of the star party. Sunday morning I had to drive back home to Chaos Manor South where stacks of ungraded student papers awaited my attention. Reluctantly, I Desert-Stormed Dobbie at about 1:30 in the am. Turned out I could have pressed on a while longer. When I got back to the motel, I found I just couldn’t sleep. Even a few fingers of Rebel Yell didn’t help. My mind was too focused on the glories I’d seen, on the great expanses of The Andromeda Nebula I’d wandered across. Me and my Ethos.