The Lyra Double-Double mounting system arrived, and wonder of wonders, I have managed to use it to attach the ST-80 to the Mak. The two-headed Frankenscope is here! MUHAHAHAHAHAHA!!!
I have the ST-80 mounted pretty much in the middle of the front-to-back axis of the Mak, so as not to affect my balance in that direction. Following the advice of Jim from ScopeStuff, I have it mounted on the right, right over the mount arm, in the right to left axis. In other words, it’s not on the very Apex of the Mak, it’s over to the right side. Keeping it here, right above the center of gravity of the whole scope and mount, avoids any additional torsion on the Vixen dovetail holding the weight of both scopes onto the mount, avoiding the tendency for them to want to rip out of the mount if the additional weight of the ST-80 were placed on the left side of the Mak, away from the mount. Or so it was explained to me, but this does makes sense.
Of course, moving it over to the right like that also lets the positioning of both EPs relative to each other work well. The photo is taken at an angle, but both EPs are in the same vertical plane with each other, although the ST-80 is about 3 inches to the right and about 4 inches higher. Since I observe with my right eye, this seems to be a perfect staggered alignment. All I have to do is dip my head slightly and move to the left, and I’m moving from the finder to the Mak. However, in actual practice, I was having a little trouble getting my eye to the Mak’s EP without hitting the ST-80’s EP on the way. Between the ST-80 and the red-dot finder, it’s a tight squeeze. I’ll have to do some more adjusting.
The way the mount works is with a bungee cord on one side, and a non-stretchable rope on the other. You adjust the knots to vary the length to ensure a tight fit, then use the plastic retainer clip to keep it in place, as you can see right in the picture – it’s that black thing on the side of the ST-80, right in the middle. There is another clip below, attaching the other loop onto the main scope. The “attachment” points – both to the scope you’re holding and the scope you’re putting it on top of, are nylonized metal, so that there is no marring the finish of either scope.
The mount itself is adjustable in the sense of moving the top scope slightly to align with the bottom scope. The four screws that hold the top scope in place – countering the tension of the bungee and rope – can be screwed in or out with an Allen wrench to make the adjustments.
It took awhile before I got a chance to use it, as the weather gods were not cooperating – as usual when you get new stuff – but I am concerned about getting it tight enough. Right now, it’s sort of tight, but it seems like it wants to slide around – both the scope in the cradle, and the cradle on top of the scope. The problem is that if you tighten it too much, and then go to unclip it – SPROING!!! Clip implanted firmly in cornea as it springs out. There has to be a happy medium; and I don’t think I’ve hit it yet.
The other concern, of course, is the additional strain on the motors because of the weight, and whether that will affect the goto accuracy. I calculated the weight – the mount, the scope, the diagonal, the EP – to come out to be just about one ounce less than 4 lbs.; adding this onto the 8 1/2 pounds that’s already attached, and it’s almost 50% more weight. While waiting for the clouds to clear, I slewed the mount around a bit, did a fake two-star alignment, and it seemed to work fine: the motors didn’t sound like there was any additional strain. Fortunately, I am still under Amazon’s warranty, so I can fall back on that if need be if anything happens with the motors. The true test will be whether this additional weight adversely affects the goto I sure hope the motor/goto still works with both scopes!
Meanwhile, while putting it all together, I was using my bed, a nice expansive uncluttered surface, for holding all the assorted nuts, bolts, instructions, and other bits. What should happen but just exactly what I was worried would happen – the ST-80 fell – whoomp – three feet from the bed onto the parquet floors. Fortunately I did not hear the sickening sound of breaking glass, and checking it, everything was okay. That’ll learn me.
Finally, the skies cleared tonight. Even though the full moon was washing everything out, I could still test the finding and tracking abilities on bright stars, the moon, and Jupiter.
Balance on this is still a bit tricky and sensitive. The ST-80 came with its own little finder and mounting rings to go into the dovetail. I decided to put the little finder on just for fun, having just gotten it and never having used the finder before. Whoops! Threw the balance right off. As I slewed up to Capella (which is very high in the sky), KLUNK! The whole tube went skyward, and the diagonal smacked into the mount.
Removing the little finder – which, with the rings, adds about half a pound more weight, and more importantly, adds that weight right on the back end of the scope – removed the problem. It slewed around fine, no more moving around unnecessarily. And most importantly, the Goto was still accurate, or more to the point, accurate enough. Because the full moon is washing out EVERYTHING, I decided it would be best, and easiest, to check the accuracy by telling the mount to go to various bright stars.
With the ST-80’s huge 4-degree TFOV, everything appeared well within it – Capella, Betelgeuse, Pollux. M42, though effectively washed out, was centered pretty well, as were the moon and Jupiter. Leaving the scope on Jupiter for an hour – as it was below freezing – it was still tracking very well when I got back. So it seems like the additional weight is not an issue in terms of the motor being able to do its job.
However, answering the earlier question, the mount definitely needs to be tightened some. It seems like it’s on the verge of sliding around every time I either go to focus it or change the EP. Lifting the scope up to bring it back inside at the end of the night, the ST-80 was practically flopping around.
Meanwhile, the Great Red Spot was supposed to transit at midnight, and I’ve been trying like crazy to see it every opportunity I’ve had. Unfortunately, the weather skunked me again, as high light clouds rolled in as the evening went on. When I went out around 11:20, there was a beautiful cloud halo completely encircling the full moon. No Great Red Spot tonight!
Finally, I’m torn about something. Amazon is currently having a terrific sale on some Celestron EPs, particularly, the X-Cel LX line and some of the Luminos line. The X-Cel LXs are almost universally regarded well – providing good value for the price. They have a 60 degree AFOV, and good eye relief. They are supposedly similar to my 15mm Paradigm, which I like. And Amazon is selling them for about 45 bucks, which is really quite a good deal, about the same I paid for my used Paradigm.
Then there’s the Luminos. It’s reputation could be described as spotty at best, and terrible at worst. This is a very-wide field EP – a whopping 82 degree AFOV That much AFOV is supposed to give a “spacewalk” feeling – like you’re looking through a porthole into space. But there is no comprehensive review of this line on any of the boards. The comments by individual users is just withering – that it’s called “Luminos” precisely because they are luminous: they have simply awful edge of field brightening so as to make the extreme wide-field all but unusable. It seems like this problem is only evident on the longer focal length models, however.
I have had my eyes on one of these super-wide-field EPs for a while; particularly the 11mm Olivon 80-degree EP. The Olivon has garnered some favorable reviews in the press – it won Astronomy Magazine’s 2013 Star Products award for best new equipment. It goes for $69, and I’ve been drooling after it for some time now. The Luminos I’m interested in would be a 10mm focal length and a slightly wider AFOV at 82 degrees. I’ve never looked through a super-wide-field EP like this, so I don’t know what it’s like, or whether I would even like it. Some people say it’s just too much – you can’t take the entire view in all at once, so you have to move your eyeball around – and that that is actually annoying.
I’m interested in these super-wide-field EPs for a couple of reasons. First to experience that spacewalk view, to really get lost in the view, if that’s possible. I also want to use it in the Mak on the moon, because it would just be able to squeeze the entire moon in and still give me 154x, which I think would be pretty neat, to have an enormous moon like that.
Another other reason is for use in the ST-80. Because it has such a short focal length at just 400mm, it needs high-powered EPs to get it up to any significant magnification. But all of my high-powered EPs are Plossls, with just 52 degrees AFOV. Strangely enough, there is actually no advantage in using the 8mm Plossl in the ST-80 to get 50x versus using the 32mm to get 48x in the Mak, because they’re both giving me almost exactly the same TFOV of about one degree. But the 10mm Luminos would give me 40x and 2 full degrees, which is a lot of territory, almost 4 times the area of the 32mm at 48x in the Mak. That would be pretty nice.
The thing is, however, is that I don’t need the Luminos – or the X-Cel LX either, for that matter. I already have EPs at 8mm, 9mm, 9.7mm, and even 10mm, most of which I still have to sell off. Sure, it would be fun to get this EP, but I’m still unemployed, and I’ve already spent far more on this whole astronomy endeavor than I ever thought I would when I was going into it just a couple of months ago – over twice as much as the cost of the Mak itself. As for the X-Cel LX, the EP I would be interested in is the 5mm, which, at 308x would fill a magnification “gap” I have between the 6mm Kellner (256x) I got with the ST-80, and my old 4mm Plossl (385x). But again, do I really “need” either EP?
On the other hand, either EP would kinda sorta be “free”, as I still have the final 60 or so bucks left on an Amazon gift card that would pretty much cover the purchase. And I could Barlow the Luminos to have both a super-wide-field 10mm and a kinda wide-field 5mm out of it. Ah, decisions, decisions.