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Tinkerbill, Jupiter and a billion volts (almost) of “first light”



Peering into the 15-inch mirror a few hours before "first light." All is well. (Click photos for larger versions.)

“First Light” is one of those phrases of near Biblical proportions with astronomers. In the most prosaic sense it means simply the time when you first use a particular telescope to see an astronomical object. But given the near worshipful approach one can have to the making of high quality optics and the telescopes that hold them, first light is more like the pat on a babies bottom as it emerges from the womb.

This is the moment when star light breathes life into wood and glass and metal and plastic and silicon, turning it all into a wondrous space/time travel machine. Photons from a distant object do their complex dance up and down the tube, bouncing from primary to secondary to eyepieces and human eyes and the experience becomes a swaying waltz you can only dance once. Yet first light happened so quickly – so matter-of-factly – for the 15-inch I almost missed it and then . . . well, let me start at the beginning.

From the morning forecast I expected four more days of overcast and off-and-on showers. But that seemed to be changing. At 4 pm - it is Friday, May 27, 2005 - just a week since I accepted delivery of the Obsession 15-inch) - the sun even peeped through a few times. So I decided to set up in the Driftway Observing Green for the first time and see if I could at least answer one nagging question – will the Denkmeier binoviewer come to focus in this scope? Or will I have to go through the dreaded pole shortening that I’d heard others have had to do?

Understand, most people still operate in “cyclops mode.” They use a single eyepiece and a single eye when looking through a telescope. But a binoviewer means you use a telescope like a binocular. You use both eyes and I am absolutely hooked on this approach to viewing the universe. It is comfortable, natural, and I have a considerable chunk of change invested in it.

Now Mr. Obsession, Dave Kriege, will tell you that pole shortening is no big pain, but I’ve heard that sort of talk from dentists before and when Dave isn’t building heirloom-class telescopes he’s a dentist, so. . . Look – I don’t even want to drill a hole in the wood, let alone cut exactly half an inch off each of eight metal truss tubes that give the telescope its length and framework. See the tubes support the upper cage that holds the secondary mirror and if you make them shorter you actually are moving the eyepieces closer to the point of focus and that’s the big question. In some cases folks trying to focus a binoviewer have run out of “in” travel. That is, they put the binoviewer into the focuser as far as it will go, rack the focuser all the way down, and there’s still no sharp image. I think the temptation to punch your fist through the side of the tube at that point would be pretty great - and this wasn’t something I could test in the house.


So I figured if nothing else I could test the focus in daylight on some land marks. So I set up the scope and popped in the binoviewer and aimed it in the general direction of some trees about 80-feet away. Too close, as I suspected. I racked the binoviewer all the way out and the trees were very fuzzy. I slid one eyepiece out of the binoviewer and held it about an inch away and the trees became sharp. Good. I knew this wasn’t a positive test, but the farther out the focuser went the better – and it was past all the way out. However, focusing on infinity would be something else.

Then I noticed some serious breaks in the clouds, so I tried to focus on the clouds. That’s not easy – when you magnify them there are no sharp edges, You’re just looking at fog that happens to be up a couple thousand feet. But as near as I could tell they came into something approximating focus with about an inch of in travel to spare. Very good.
And then I looked up in the apple tree and on a thin, dead vine emerging from it’s, there was Tinkerbill, staring down at me. And boy, that was very, very good. I paused, folded my hands, and bowed to him Hindu fashion, my heart full of joy. You see I love this feisty little guy and all day the thought that he might have been lost in the recent storm had gnawed at my heart.

Tinkerbill is a ruby-throated hummingbird who has been entertaining us for the past week or two with his antics as he stands guard over the hummingbird feeder and does wondrous, zooming figure eights that are so cool they’d make the Red Baron blush with envy, I assume he does them to impress Tinkerbelle, this svelte little charmer and I have hope that it has worked. At least I haven’t seen her around for a week, so she either stood him up and went hunting elsewhere, or she’s sitting on a nest right now, hidden in some nearby tree.

But we’ve had a three-day nor’easter, very unusual for this time of year, with horrific winds that scattered green leaves, small branches, apple petals and huge chunks of lilac blooms all over the yard and I really worried about Tinkerbill and Tinkerbelle. Hey, these folks had flown up here all the way from Central America, a hell of a trip for a bird of few grams, honeymooning inour backyard and watching over my final struggles to complete Driftway Observing green. And when I didn’t see Tinkerbill any time during the day, well . . . I feared the worse.

But back to the scope. It was now 5 pm and darned if the skies weren’t clear. Hot damn! Not only that, the TV weather folks were saying it was going to be clear tomorrow – so I assumed that meant a clear sky tonight and no moon until after midnight. Wow! This would be it – first light! I sat down at my computer and mapped out a plan, listing a few dozen “must sees” for the night. Dave had cautioned me to use the scope manually the first night out. Then the next night introduce myself to the Argo Navis digital setting circles, then the night after that add the ServoCAT drive system. Which automatically tracks what you find. So that’s what I planned to do – yeah, sure - for the first fifteen minutes or so. Then I wanted those digital setting circle up and running because there was no way I was going to find all those things on my list manually in the three hours of dark skies I could count on before the moon rose. Besides, I was as excited as – well, as excited as Tinkerbill doing his spiffy figure eights in the air – though my excitement had to remain bottled up.

Trouble is, as twilight deepened so did the clouds on the northern horizon. Bren came out to take a peek at Jupiter. fl_jupiter.jpg Jupiter from Starry Nights planetarium software.
Yes, I found Jupiter first – despite the fact that the Telrad finder – which wasn’t even aligned – had already dewed up. Dew and it wasn’t even very dark yet! Not a good sign and hey – THAT WAS FIRST LIGHT! Where was the champagne? Where was the awe? Jupiter is so bright it was one of the first things visible and with hardly giving it a thought I turned the telescope to it. I got wrapped up intrying to find things in the foggy Telrad and it took a little searching around and then bingo! Big as life, there was Jupiter with three of its moon bunched off to the left and its familiar three or four bands. Not a bad view, buit nothing to write home about – no would I expect it to be. I expect this scope to give very nice views of the planets, but I also expect them to be very limited by atmosphere turbulence and while it was clear, the air was far from still. (Someone’s got a good solution for the Telrad dewing up, right? I sur ehope so. I blew a little air on it from a portable fan and that seemed to help, but . . . ) Anyway, I had Jupiter in the binoviewer at something like 115X and yes – in was sharp focus. So not only did I have first light – planets count, right? – but I had sharp focus and room to spare – and that means no tube trimming in my future. I should be doing a little jigh about tis point, but still I was sleep-walking. Everything was happening fast and matter-of-factly. (Oh – for the Obsession-user crowd - I’m using the FeatherTouch focuser and I’m really not sure why this all worked. I don’t knw if I should credit the folks at Denkmeier. I have their OCS system installed as well. Or whether Dave made the tubes a little shorter than normal knowing I was going to use a binoviewer, or what. But it works!)

Then Bren was at my elbow. I knew she was tired and wanted to go to bed after a day of work that ran right into a non-stop evening of Girl Scouts with our grandchildren. But here she was and I had someone to share Jupiter with and she looked for a while and was duely impressed, then let me look. I was simply delighted just to be seeing anything and the image seemed very good – but I just didn’t get a long enough look to be sure before the clouds closed over it. Bren said: “Is that lightning?” And I said “Nawwwwwwww. Probably car lights – or maybe that searchlight up north bouncing off the clouds.“

I’d seen patterns like this before. The skies could be clear in 15 minutes. I’d wait it out.. I watched Jupiter through the binoviewer, glow light and dark like some giant firefly as the clouds first gave it to me, then took it away, then brought it back again. I noticed brilliant Arcturus has a clear patch of sky, do I dodged over to it – I had blown away enough of the dew from the Telrad to make it usable and even aligned it so ti was accurate. (When did I do that?) Arcturus looked huge and there was a moment when it gave me those long spikes like the star of Bethlehem on a Christmas card, then it settled down to being a bright orangey blob. And then the clouds covered it, so I jumped back to Jupiter which had re-emerged for a moment and the clouds covered it again.

I looked around for other breaks in the sky. None. Was that lightning? Nawwww….but I was less sure this time. And the search light came by again, reflecting off the bottom of the …was THAT lightening? You bet it was. Uh oh. Yes, I had a storm cover, but I wasn’t ready to trust it to protect stuff from a billion volt shot of first light, not to mention wind gusts and hard rain, So I decided this was going to be a great test of how long it takes me to put everything away. I knew it would be more than what you see in the Obsession video. What you see there is honest and accurate. Even I can put up the scope and take it down and attach the wheels and wheelbarrow handles all in about 10 minutes and I’ve only had it a week. But there are eyepieces and binoviewers, and Telrads and wires and the Argo Navis computer and the ServoCAT and hand controller and it all adds up to several trips from the Observing Green to the house 80-feet away..

My first priority was the scope, but the first thing I did was remove the eyepieces from the binoviewer and boy was I cursing Denkmeier for their cleverness. See I have a pair of Denk 21s and they screw into these wonderfully-machined eyepiece “safes” – very clever - except I always find it a little difficult to thread the eyepiece into the bottom of the safe and with another lightning flash of the intensity that left no doubt I gave up and just put everything in its aluminum case so it was at least under cover. And not too soon. There was the first drop of rain.

I took the scope down and wheeled it the 80 feet to the house where I put down the plywood ramps and got it undercover with nothing except maybe a dozen small rain drops on it. Thankfully this was not one of those sudden downpours. It started slowly. So piece-by-piece I retrieved everything else and while I got wet doing this, nothing wood or electronic got wet – I was able to protect it all. In fact, before I took the scope in I had thrown the AstroSystems cover over the upper tube assembly and the electronic gizmos. And it all took 21 minutes exactly - no kidding, I timed it with my voice recorder which timestamps every new note!

So here I am, shaking and damp and my back a little sore – I did something too fast – and my mind still trying to grasp first light and the rational piece of me more than delighted that it wasn’t indeed, a one billion volt flash. There was lightning, but it all stayed pretty far away. So while I sleep-walked through my magic moment, I still think I’m going to remember this night! And there will be another clear night soon and then I hope I can focus in on what I believe is a really worthy, first light target – the star cluster dubbed “M3” - one of those wonderful snow globes of half a million, close-packed suns that I’m sure is going to look more dazzling in the Obsession 15 than in any scope I’ve ever used.

Posted by Greg Stone at May 28, 2005 04:44 AM Comments? Please email me: gstone@umassd.edu

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