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Archive for August, 2010

Just did a few quick test. With a near full Moon less than five degrees away I wondered how easy it would be to pick out Uranus in the glare.

1. Celestron 15X70 Skymaster  – Easy. i could see three of Jupiter’s moon to one side of the planet and could easily pick our Uranus.

2. Pentax 10X50 PCF WII – Moderately difficult. I could catch one – maybe two – of Jupiter’s moons and Uranus, but it helped to use averted vision.

3. Bushnell 6X25 and Pentax 6.5X21 – Very difficult. I felt I could glimpse Uranus, but only because I had seen exactly where it was using larger binoculars.  However, without the competition from the Moon it should be easy even  these binoculars.

In all cases I hand held the binoculars. Handholding the 15X70 Celestrons goes completely against everything I know about binocular use. But. I really enjoy using these for a quick look and while they shake, the extra light grasp more than make sup for the shaking.  I am amazed at what I can see with these, especially since they are very inexpensive. I paid $45 for mine used and  that included shipping. They are in like new condition. The sharpness drops off rapidly as you move away from the center of the field of view,  so I don’t think these would be nearly so satisfactory if you mounted them and used them for serious binocular astronomy. But as a “quick look” device I’ve never had anything so good.

Besides just casual touring, they are also useful doing some preliminary star hopping – surveying a region before I turn the telescope on it.

They were head and shoulders above the 10X50 glasses I usually recommend for hand holding when it comes to finding Uranus, or seeing the moons of Jupiter. They have really changed my thinking about binoculars for astronomy.

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I was real pleased when I found the SV80S Lomo perfectly fit the saddle that was on a Celestron – made in China – FirstScope 80 equatorial mount that seemed to be pretty solidly built.

However, before I went out to  observe I did notice one major flaw with  that mount – the slow motion cables attached only to one side of the mount – one on one side and one on the other! What were they thinking? That would be a problem, though the mount seemed to move so smoothly I wasn’t sure I would need the  cables much.

I put the scope out on the rear deck with all related gear as the sun set. I returned to the house and napped in a darkened room through twilight so my eyes would be dark adapted and I could take advantage of the hour or so of dark skies before moon rise.

Wrong!

I spent the next twenty minutes trying to make a single adjustment – the one where you set the latitude. I was doing this by aiming at Polaris and no way could I center it. There was significant play in this motion and every time I tried to tighten it up – not easy since  there is no stop on this mount, so you have to tighten real tight – every time I did this it would move and Polaris would end up being off by at least a full degree. I usually don’t worry too much about that, but the play in the mount bothered me and I wanted to get it right. I couldn’t. I tried over and over again, trying to second guess it by going past the point where I wanted it to stop. I finally gave up and decided to get the 76mm Tasco out of the telescope shed. That meant a long walk with a heavy scope and mount in the dark, plus more set up time, but at least I knew that scope would work, though the mount has a flaw in the RA motion.

Wrong!

After aligning it with reasonable success on  Polaris I decided to hunt down Mu Draconis for another look. (Polaris and companion had shown nicely indicating both decent seeing and transparency.)  But first I thought I should reposition the tripod and then swing the whole head on the azimuth bearing. Uh oh. I could barely get it to move. Well, maybe it wouldn’t matter. I pointed the scope towards Mu, high overhead. Ooops. It hit the tripod leg. Have to move the tripod and adjust that azimuth setting. What the heck is wrong? It’s taking all my strength to barely budge it!

Maybe the scope isn’t quite level and it’s binding? Yeah. that looks like the problem. So I go to adjust the offending tripod leg and the bottom half falls out on the deck and since these legs are round, it rolls away from me – leaving me  trying to act as the third tripod leg while I grope in the dark for the stray limb. That comedy of errors came to a successful conclusion and I got the tripod adjusted so the head was level – but I still needed all my strength to move it in azimuth just a little.

Frustrated, I look quickly for  Mu and with luck, find it right away. Not only that, but it splits beautifully – easier and better than it had the other night. But now the scope is hitting the tripod leg and I can’t follow it as it drifts out of view. That’s it. I’ve had it with equatorial mounts for the night. I want to see if I can split Mu with a 60mm anyway. What I need is that nice, simple, light weight Unitron 114 alt-az.

So it’s back to the telescope shed in the dark and this time I carry the Unitron, fully assembled, back to the deck.  It’s so light you can do it with one hand. This is surely the way to go.

Wrong!

The moon is already starting to rise, but that’s OK – the night is still clear. The  altitude slow motion has run it’s distance, so I have to back it way off. I have trouble getting the altitude lock at just the right tension. The scope swings wildly. I don’t remember that being a problem before. But not insurmountable. It is frustrating though. The azimuth lock also is giving me woes. I must be sending bad vibes to it. But after fooling around with a wide field eyepiece and not finding Mu I’m getting frustrated. I finally turn to the dinky little finder on the Unitron which is positioned so it’s easier to use than most when the scope is pointed near vertical. Bingo. I find Mu with it. Great!

But wait – I can’t focus. I push in the draw tube and it keeps losing focus. What the heck is going on?  The tightening clamp doesn’t seem to be holding. The weight of the Unihex and 1.25-inch eyepiece seems too much when pointed high up.  So I remove the Unihex and go in the lighted house – the hell with night vision. A gibbous moon is already high enough to put that out of play. I look in the closet in the basement and find the other tube you can use with a single eyepiece. I steal the  diagonal from the 76mm Tasco. Great. I’m in business. There’s Mu and I’m able to split it with the 60mm. That’s enough success to bring my mood back to an even keel.

But it’s all I can do to see the companion of Polaris with this scope – even when I first set it up with the moon very low.  And while the split of Mu is technically satisfying, it’s a borderline thing that doesn’t leave me feeling real good. I’m not that thrilled with pushing a scope to it’s edge. I want a more satisfying view of something.  And while I’m getting the hang of the correct tension of the lock knobs on the two axis, I’m finding it a pain. What I really need to do is return to the SV80S Lomo. It is a real nice scope and if I put it on a modern alt-az mount like the Voyager I’ll be happy. Should be easy to do.

Wrong.

First, this means I have to put the clam shell back on the  SV80. The clamshell has two entirely different screws – one short that needs to be turned with a hex wrench – and one long with a knob on the end for hand tightening. I assembled it once, while sitting on the couch, and it doesn’t seem right. The  knob  seems as tight as it can go, but the scope is still slipping in the  clam shell. I back off of the knob – and the knob comes off the screw, leaving the long screw in place with no way to loosen it. Is it cross-threaded? I’m worried, but I get a pair of vise-grip pliers and gingerly clamp down on the screw, hoping I’m not damaging the threads. I loosen it.  Good. I reverse the screws – though I don’t see any reason why this should make a difference. I return the knob to its screw and am able to tighten it so the scope doesn’t move.

OK – now to the shed where the Voyager mount is  in pieces – the head in one place and the tripod in another with an old parallelogram mount on it. No matter. I’m going to make something work right tonight! But there’s no way I can lift the p-gram mount off its post. It sometimes sticks, but this is ridiculous. Again I’m using all my strength and it won’t come off. So once more I am fumbling in the dark – this time with a wrench trying to undo the post. I know this isn’t a real good idea and I’m right. i finally get it undone and sure enough, I jam  two or three fingers between the bars of the the p-gram forced together by the counterweight. This can happen with this mount, I thought of it in advance – but I didn’t think eenough. So I’m sitting there on the floor of the shed in pain until I finally extricate my fingers!

Geeze!

I get the Voyager head onto the tripod and the Voyager is read to do its thing.

RIGHT! Yes, this operation went right. The Voyager/SV80 combo proves to be so good I return to the shed for the eyepiece tray that I had custom made for the Voyager. It goes on correctly. Nice. The scope is on, the eyepiece tray is on, and I have a sweet split of  the double double in the SV80S Lomo – but not quite as good as I think it should be. Some clouds are moving in as well. Still – I’m starting to wonder if the TV Plossls just aren’t the right eyepieces for this very fast scope?

I go get my collection of Naglers. Return to Mu. Yep! The Naglers do a better job than the Plossls. A little more contrast and they are sharp to the edges – the Plossls weren’t. What’s more, the best views come from the Nagler 6-3mm zoom. This is a wonderful eyepiece. It works well with the long focal length scopes and well with the short focal ratio scope. Amazing. If I keep using this scope I may get the 4-2 Nagler zoom!

My cleanest, most satisfying split of Mu comes with the zoom at the 4mm click stop – 120X, Nice! My spirits have moved over to the positive side  of the register. What’s more, an old favorite, Iota Cassiopeia, is above my tree line now. I go for it. Wow! Beautiful – just beautiful.  With the 6mm zoom a pin prick of light appears cleanly – widely – separated form the primary, Go down to 5mm and the the closer – brighter – star is separated from the primary now. At 3mm setting Iota Cass becomes the precious gem that it is.

This is what it should be like. And the Voyager mount is absolutely smooth and provides no frustrations. All works as it should. But the clouds are getting pretty thick now.

So I do a quick look at the moon with the zoom still in and cranked up. Wow! 160X never looked so good. And I quickly reposition the scope so I can get past a tree and see Jupiter. Very nice. No South Equatorial Band yet, though some hint of it.

I got a lot of stuff to put away, but I have at last found a combo of scope and mount that will move easily in and out of the library to the deck for quick set-up and fun star-splitting – plus a lot of other exploring.  Oh – and I can use the 30mm Clearvue with this scope to get a 5 degree fov and so I don’t need a finder at all.

And did I mention that’s what I used to find the third set of Dragon’s eyes? 16 and 17 Dracomis? Well it was and it worked like a charm.  Yes!

Like Shakespeare, I now need one of those famous quotes to sum things up. How about “all’s well that ends well?” At least for this night. 😉

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