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So I've
been working on a trailer (3/21/2009). Not the kind I worked
on a couple of years ago ("book trailers," where we tried
to sell books using a labor intensive product designed by and for
people who'd rather wait for the movie; that was bright, wasn't it?).
But the kind that will let me haul a telescope up 'n out from under
these piney woods into the big clearing at the top of the driveway.
There'll be some nifty metalwork See, I looked at these ScopeBuggy things and think they're the right idea for me, but my driveway is 550 feet long and much of it is steep. How steep? You know those ">>"symbols you see on Michelin maps of Europe? The ones that mean "28% grade" (which means, "gear down just thinking about going here" or "in a Citroen!?!" or "if you're abike, put it in granny and be prepared to push")? My driveway has one of those right in the middle. Can I pull a ScopeBuggy with 150 pounds of mount and battery and maybe telescope on it over my own private Applecross? If I could, would it stay upright? (Would I?) Could I keep it from accelerating to 90mph on the way down? I have my doubts. So I need to build something to order, a ScopeBuggy-like contraption that I can hook behind the Civic from time to time, one that will still let me roll the 'scope around the backyard when needed. On the way are two square tubes of mild steel (2x2x48 inches each, 3/16-inch walls); two 10-inch pneumatic wheels; a handful of scrap aluminum pieces to mate wheels to steel. See the image at left: start with a couple of 2-inch diameter aluminum billets and turn most of the length of each (on an 1890's bench lathe -- there's a story I need to get around to, too) until the bar just slips inside the steel tubes. Put a 5/8-inch hole through the center for a big bolt to serve as an axle. Drill some blind holes into the aluminum and line 'em up with holes drilled and tapped in the steel to receive 10-24 socket head screws. That ought to keep the axle adapters in place. Still percolating in my head are schemes
involving eye-bolts and u-bolts for tie-downs All in all, it'll cost me a third of what the commercial product would and (more importantly) it will keep me out of more expensive trouble for weeks. Also, it'll allow something only a fool would allow with a commercial product: towability. Eventually, I ought to be able to put the carrier behind the Honda and tow an almost-assembled observatory up to less obstructed skies (keep reading!) and finally get back to gazing upon and photographing Things Out There. While the pieces flow this way and while a few auctions for elusive bits close, it's back to three or four websites, 29 (!) weddings (there'll be a story about that, believe you me), 15 musicians, and a couple of recalcitrant projects that just will not end, for better or for worse. Stay tuned. APRIL 22: Here's a look at the work in progress when the trailer provided just enough mobility to let me dodge trees to photograph Venus and the Moon in the bright morning sky. APRIL 25: Hey, hey, boys, I scored another APOD with a shot I got on the 22nd. Thus inspired, I doubled down to finish the trailer and its minimal accessories. I decided to use the shorter, fixed length legs Scott Losmandy used to sell for the G11 (it was just too tall on the longer legs) and I painted the trailer International Harvester Red in case I ever decide to attach a disk harrow behind it -- also in honor of its job in tilling the skies for magnificent views and creditable photos. And so I can see it clearly in the dark by the glow of a red flashlight, thus minimizing the chances of ruining a photo (or breaking a bone) by kicking the bejeebers out of it. I took three blocks of 6x6 treated pine of various lengths (leftovers from porch construction) and cut 2-inch wide notches of assorted depths on assorted sides. An engineer could pass some quality time working out optimal lengths, depths and arrangements of each cut; a mathematician could make a career out of it: a multi-dimensional die problem with entailments in group theory lies literally within my grasp and just as literally beyond my understanding. I just made dado cut after dado cut until I got damned tired of cutting dadoes and was covered in sawdust. The blocks go under the trailer to get it up off the wheels which wobble a bit ("a bit" means a helluva lot more than the arc second or so that would be tolerable) and the different depths and lengths give me a wide range of adjustment so I can get the platform reasonably level just about anywhere I'd be willing to use it. There aren't ten level feet in this development, let alone in this yard, so the Euler Blocks are important. APRIL 26: Sea trials! On the 26th, the Moon stood low in the evening twilight over the planet Mercury. I hadn't a prayer of seeing that from down in our holler. But up top, west of the driveway where the road straightens out, the pair should shine right through the corridor of pines. Ought to be lovely. So I hooked up the trailer, cradled the A-P in the trunk, and off Amy and I went. I watched the G11 in the rearview mirror and drove by peripheral vision. Amy's job was to let me know if small children or cats were in danger of getting caught up under the car. Also to listen out her window for suspicious clunks, tinks, or metal-on-pavement cacaphonies that might signal the impending departure of the G11 from the Honda. I kept it under 15 mph and never left 1st gear. Worked GREAT. Except I was so excited I forgot the camera adapter for the telescope and all the 6-inch dice with which to level the outfit once we got the Moon in sight. So I have no first-light photos to share. Still. It worked a treat and we enjoyed a razor-sharp view of the thin crescent in the twilight with Mercury shining brightly down below. Couldn't do that from down here under the trees. No sir. We took the outfit home early even though I thought Earthlight would soon make the view of the young Moon breathtaking; I wanted sufficient light to see mayhem in the making as I came down the driveway with the rig for the first time. More
when I
April 27: I upgraded Maxim DL from 4.56 to 5.06 on the promise of better and more convenient stacking performance (and support for Canon 50D RAW files), but today's revelation was Photoshop CS4 Extended's vastly improved stacking abilities. I bought Stefan Seip's book Digital Astrophotography to be sure I understood how stacking in Photoshop worked, but quickly discovered that technology marches on and that CS4 Extended offers more workflow-friendly means than I have found documented in print (still reading, still looking...). For the current state of my art in stacking data for improved s/n, see the newly processed Venus and the Moon photos with the cratered, rough-hewn Moon dragged kicking and screaming out of the pale blue sky. May 1: Harbor Freight's been getting a lot of harsh comments on the net about products not being delivered, but you won't find any grousing from me about this order. This just arrived via FedEx Ground exactly when promised. Go to www.harborfreight.com and search for "trailer dolly" and then send your $50-60 (search for coupons first, a step I neglected to the tune of a pretty nice if not entirely free lunch). This is the heavy duty model, good for a tongue weight of 600 pounds. I need to lift, oh, 20, but the lighter version of the dolly is not much smaller and there's not a lot of room for money-saving in this price regime, so take your 3000% safety margin and be happy with it. Who knows, you might need to move an RV or a very large boat as a favor to your neighbor at some campsite. Besides, the bigger wheels will cushion the ride and make even my backyard readily navigable. One thing: the directions were useless and while the way I got it together works fine, there were parts left over. Also, at one point I threw up my hands and in a fit of uberpragmatism put the handle under a drill press and put a hole where I needed one. That sort of thing's always just a little scary, but hell, it's not an airplane. I mean, at worst, maybe I won't have my full three thousand percent margin; it'll be fine. I just dragged the mount all over the yard just to be sure the dolly works as well as I thought it would. I should've timed it: from G11 , battery and blocks in the basement to a mount ready to align might have taken two minutes. Certainly not more. That'll do.
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