23 Jul, 2009

I haven't added anything in the past year, because the (too few) nights I had the scope out provided no new information: fun and good viewing, to be sure, but nothing remarkble (pro or con). But in the last week, I've been back out in New Mexico, same place as last year, and have had two spectactular nights--one coming after the biggest rainfall they've had here in years. So this seemed like a good time for a report on how the scope is doing, after a year and a bit of ownership, under nearly pristine skies.

First off, not a single problem with the scope so far. And it's seen a lot of bumpy roads, as well as its share of nights outside under a cover. Given how dusty it is up here, a mirror rinse may be in order sometime soon; but that's it. The scope continues to hold colimation very well. Nothing new to report, and on this front, no news is good news.

I didn't do a careful test of the conditions on the nights in question. I was viewing as much as possible. But stars of magnitude 6.7 near the Little Dipper were not hard to spot. On the first night, the transparency was very good, though the seeing was not. On the second night, the transparency was OK, but the seeing was terrific. At the end of the second night--spent with Jupiter, watching Callisto's shadow near the great spot, and occasionally sneaking off for very nice views of Uranus and Neptune--a light wind was the limiting factor on magnification. No matter how much power I threw at Jupiter, the image was sharp and steady when the wind calmed. But I "settled" for 300-500x, and was delighted the next morning by how well my eyepiece view matched the image provided by SkyTools3.

Sidebar: I am writing during the day, of course, and have just paused in order to fail (yet again) to get a photo of the road runner who often goes past the house. Indeed, it sometimes knocks--well, pecks--at the glass back door, and has hopped up onto the lounge chair outside. But each time I reach for the camera, the bird either disappears, or something goes wrong: no card in the camera, it was set for 2 second delay, the battery just gave out; I drop something that makes a big noise; the back door sticks; etc. I have put a small dish of bird seed near the door, and will soon be ordering my Acme catalog. But back to night skies...

Looking at a series of NGC galaxies that I hadn't seen before reconfimed that the 18FX does really well on faint fuzzies, and that the slewing/tracking remains very accurate. (Likewise for planets. I was quite impressed when a later slew from Neptune to Uranus put the latter in the field of a 7 Nagler: push GoTO, and there you are; hard to argue with that. ) I hadn't seen Stephan's Quintet since the last time I was at this site. My notes suggest that the view then was impressive, though even better this time. But the optics really strutted their stuff on globular clusters and big nebula. Regarding the latter, views of the North American with a Pan 35 and a nebula filter were jaw dropping--perhaps the best overall views I've had in any scope, since the greater detail visible with a signicantly larger f/4+ mirror greatly reduces the field of view. (I haven't yet had the chance to look through one of the new f/3.3 Starmasters.) Ditto for the Veil. I continue to be very happily surprised at how well a Pan 35 works in the scope. Switching between this lens and an Ethos 13 on a Milky Way nebula tour kept me occupied for a long while, especially once I got to the Eagle. I'm quite sure that I saw pillars, during an extended period of sitting steadily. When I got up from the scope, the Milky Way was directly overhead and almost dazzlingly bright.

Indeed, conditions were good enough to spot the central star in the Ring Nebula. It took high magnification and a little scope jiggling to get the star to emerge, more or less clearly, from the soup for the first time. But once I had it, I was able to reduce the magnification a bit and get a larger field of view, leaving more room for averted vision. (But since the nearby 13th magnititude star was annoyingly bright, I tried to keep it out of sight.) Racking in and out a bit provided several clear glimpses, including one during a moment of especially steady seeing that revealed a lovely green-blue spark.

Hard to ask for more from a very portable telescope. Get it under good skies, and it doesn't get in the way; it makes what good skies offer readily available. Easy to set up, easy to use, easy to break down. Getting and keeping precise collimation is not a chore; nor is cooling the mirror, as I noted before. Pushing the scope around and star hopping is fun; but the software and hardware do their jobs admirably, with less battery drain than I would have expected. I push more buttons than I did a year ago, and don't regret it. My wife Sue (63" tall), pictured below with the scope at dusk, loves getting quick tours. 

As a result, she's much more interested in astronomy than she was 18 months ago. And while I hate to admit this matters, the scope just does look good--in use, and even in the basement at home, For what it's worth, I have stopped thinking about an 18" f/3.7 as either large or fast, and not just because Singmaster/Lockwood keep pushing the envelope. And it's not that I want anything else; anything larger wouldn't fit through the back door of house. It's that after a year and a bit, the 18FX just seems like the size of a decent telescope, and pleasantly shorter than just about all the others that can show as much. 

I'll be out here a bit longer, and will add a few more observing notes. But then I'll call it quits on this "report." Bottom line: still very happy, and now fully comfortable with the scope.