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Posts Tagged ‘M81’

After a hiatus of about four years I am back into deep sky video astronomy with both feet. The object of this form of astronomy is to provide live video views at the telescope – under the stars – which show far more detail in faint, distant objects than can be seen visually with the eye at the telescope. The video camera, a special one made by hand in Canada by Rock Mallin, simply slides into the telescope where the eyepiece normally goes.

This is not rocket science, but there are a lot of options, a lot of wires, and some stuff to learn, so at this stage my efforts are crude, but I’m happy with the results. I don’t see this as competing with still imaging where much different cameras are used to take super pictures which are then enhanced the next day in the computer.  What you see here is raw video – what you would see if you stood by the telescope and looked at the video screen. I discussed the reasons for doing this  in detail in a post about six years ago when I first tried deep sky video.

Yeah, Driftway Way Observatory looks a bit techy these days with all the wires and things 😉 That little screen about the size of a deck of cards is the recording device from Orion. It includes a nice monitor which is shown here displaying a menu. The whole thing is small and light enough to ride ont he telescope. (Click image for a larger view.)

Last night I tried for the first time  an Orion StarShoot LCD-DVR recorder – this is a new item – so new the Orion sales and technical folks could not answer my questions a couple weeks ago because they hadn’t seen one yet. So I decided to buy one and give it a try, since Orion has a reasonable return policy. My assessment? Neat. I like it. But then. I’ve only spent an hour with it. However, let’s cut to the chase. Here are most of the recorded videos from last night.

My first stop was M3, a globular cluster , and the different versions of it you see on the followingvideo are due to my playing with the MallinCam controls -sometimes taking very short exposures, sometimes longer ones. Also, the  drives on the LX-200R hadn’t really settled down yet, so you don’t get a satisfying – to me – view until the end of this brief clip.

About viewing these clips –

1. Enlarge to full screen if possible by clicking box in lower left.

2. Don’t treat like a normal video – there is no relevant sound and there is virtually no action. When you see something you like, pause and view as a still image.

3. Make liberal use of the slider beneath the video to jump from one section of the video to another.

Colliding galaxies

This next one is of one of my favorite galaxies – or rather, colliding galaxies – M51. Though I have viewed this countless times over the past 40 years or more, this is the first time I was really aware that the core of the smaller galaxy is much brighter than the core of the larger one. (I explore just that idea in another video later.)

I jumped from M51 to a much different subject, the Owl Nebulae in Ursa Major – M97.  I have always found this planetary nebular difficult visually, but in the video it’s fairly easy to see how it got its nickname. This won’t be obvious until I increase the exposure in the second half of the video.

From the Owl I went to another difficult, but astounding subject, m101, the great Pinwheel Galaxy just off the Big Dipper’s handle. This is notoriously hard to see visually, but the spiral structure, while subtle is easily seen – especially in the longer exposures near the end of this video.

M81 is best known, perhaps,a s the companion of M82. The two galaxies are fairly near to one another – and to us (11 million light years) and both can be seen int he same binocular field of view. They are quite different. M81 is a bright spiral – however, the spiral structure takes alot of exposure to bring out and only becomes apparent inthe second half of this video.

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Is an 80mm, richest field refractor really the Goldilocks scope?  Not too large, not too small – just right! If my four hours of observing last night is any indicator, the answer is “yes!”

I’ve owned two smaller scopes I thought were terrific – an Astro-tech 66 and a 60mm Televue. I really didn’t like parting with either, but priorities change and while I got some good millage out of them, I didn’t use them that often. Why? Certainly not for lack of portability because they are as portable as it gets. And the quality on both were stunning. And they always delivered more than I expected.  But, in the end for me using them was more a stunt – more an attempt to prove to myself how much I could do with how little. For someone else – especially someone who travels frequently – the portability may turn these two scopes into something much more practical than a stunt. But I rarely travel beyond my neighbor’s yard. My idea of portability is being able to move 10-feet to avoid a tree that’s blocking my view.   And I don’t really need  the quick-look capability of “grab and go” when the scope in my observatory can be operational in two minutes flat and the 15-inch in less than five minutes.

So when I say portable what I really mean is my aging muscles should be able to easily pick up the scope and tripod and move them 30-feet without any heavy breathing. In fact, I should be able to carry the scope, tripod, eyepieces, and my folding observing seat all on one trip. With the 80mm on a Voyager mount that’s possible – though I admit, it was certainly easier with the 60mm sitting on its Bogen tripod. OK, maybe it would be more sensible to make two trips sometimes 😉 But what I’m buying on the used market may fill that bill – along with what I have on hand now and what I learned from using a similar-sized scope last night.

Let’s start with the new – to me -scope. It’s known as a SV80S Stellarvue. It’s apochromatic triplet objective was made by Lomo, a Russian firm, and is legendary within the circle of small refractor fanatics. (I’m an apprentice member of that circle.)  Here are the highlights from Stellarvue’s Web site where they still offer a limited number of these for $1,795 new. (What I  assume is the Chinese version – probably as good – sells for $600 less.) I’m getting one that’s four years old and uses the Lomo objective and I’m paying $1,000 – far more than I ever thought I would dream of paying for an 80mm scope. Oh – those highlights are:

  • 80mm f-6 480 mm apochromatic triplet
  • Fully multicoated objective for both visual and ccd use
  • Stellarvue’s exclusive easy one touch cnc clamshell mounting ring with Vixen rail
  • Genuine Feather Touch 2″ dual speed focuser with compression ring 1.25″ adapter.
  • Retracting dew shield
  • Instrument White high temperature powder-coating
  • C7 side reinforced airline carry on case included (shown with optional accessories)
  • Each one is triple tested including a star test by Vic Maris

It’s about 16-inches long and 7-8 pounds with diagonal and finder – though I’m not at all sure I’ll use a finder on it. More on on that later.

Sounds great. And while mine will come with the original – smaller – case, I can purchase the case pictured here for it and that is a key to portability because of the great selection of eyepieces and accessories you can include.  So I’ll invest another $70 and get this case just to make  the whole observing set-up more portable. (Generous Astromarter who sold me this scope include the larger case, a televue 2-inch diagonal, a red dot finder, and a solar filter! Very nice package deal, all for theoriginal price!)

But is it really necessary to go to this extreme quality? Honestly, I have my doubts.   I mean I know color will not be an issue with this scope and the two-speed focuser is very helpful with any scope this fast where focus is more critical than with slow scopes.  But will this outperform a Short Tube 80, the ubiquitous little Orion that can do wonders and can be bought used for one tenth the price? Yes – absolutely. But how about a higher grade scope like Celestron’s Onyx 80? I have one, was planning to sell it, and that’s what I was using last night. The Onyx is one slick little scope and its optical performance is very nice. I’m going to hold on to it long enough so I can do some side-by-side testing. I hope the Stellarvue will have the edge, but at more than three times the cost of the Onyx it should.  (Update – never did the side-by-side. Sold it before the skies cleared.)  Yes, as you pay more the cost per unit of improvement goes up – I don’t expect to see anything but a slight improvement – but I hope I’ll see that. And there’s something more involved – the scope has a sort of history/personality built around its Lomo lens. And there’s a certain satisfaction in knowing that you are using the best, therefore if you are failing to see something you expect to see, the problem is either you or atmospheric conditions. You’ve pretty much eliminated your equipment as a potential source of problem.

I decided to use the Onyx last night because it was handy and because I wanted to see just how much I could expect from an 80mm scope, since I’ve been using either 60, 100, or 120mm lately. Here’s Celstron’s talking points on the slick little Onyx (no longer in production):

Onyx 80EDF – General Features

  • Premium 80 mm refractor
  • Celestron’s Starbright XLT high transmission coatings
  • Celestron combines a Fluorite based, low dispersion glass with high density crown glass for virtually color-free images across the visible spectrum
  • 2″ Crayford style focuser minimizes image shift
  • Rotatable focuser for easy framing of objects for photography
  • Extendable lens shade reduces glare and protects lens from moisture
  • Built-in sighting scope to help accurately locate objects
  • Integrated dovetail compatible with Celestron Computerized “GoTo”
  • Aluminum case for convenient storage and protection

The one worth singling out here is this one:

  • Built-in sighting scope to help accurately locate objects

This is a big mistake. It’s not a “sighting scope” at all – just a peep hole and as far as I can tell it does no good at all.  However, it is removable (one screw) and I’ve put a Rigel finder on there in its place. I also mounted a laser there. But I didn’t have either of these on it last night. Instead I simply used a 24mm Panoptic. (A 24mm Hyperion or 32mm Plossl would give the same field.) The result is a true field of view of about 3.2 degrees which is typical of the field for large astronomy binoculars. In fact many give even smaller fields.  I found the combination of the large field, plus 80mm of light-gathering power in the objective , makes it very easy to find everything from planets and bright stars, to very faint, low-surface brightness deep sky objects like  M33. What’s more, once you find them it’s a simple matter to boost the power. (I had tried a bargain-priced, 30mm eyepiece with an 82 degree apparent field of view. Works fine and delivers almost  five degrees true field. But I find it a bother going from this eyepiece – which is a 2-inch- to higher-powered 1.25 inch eyepieces. Hmmm. . . if I were using all Hyperions that wouldn’t be an issue. Anyway – little stuff like that can put me off sometimes. I don’t like fumbling with small parts and set screws in the dark any more than I have to. )

But this is “richest field” aspect is really one of the most impressive things about using an 80mm scope with a short focal ratio thus making the scope its own finder. I found deep sky objects in particular easier to track down with this scope than with  the typical finder, whether it be a Rigel, red dot,  or 8×50 optical finder. The key, of course, is the light grasp. Another key is being able to sit comfortably behind the scope, as opposed to using a Dob where you sit at the side. Sitting behind this scope I found I very quickly developed a pretty accurate sense of where it was pointing – a sort of shoot-from-the hip type of thing. I don’t know how to teach it or even explain it, but it just feels natural. Look at where your target is and while looking, point the scope. I think your eye-brain work to deliver a solution if you get out of the way!  If you’re off a little, start a systematic sweep and you should soon pick up your target – assuming, of course, you have some idea what your target should look like!

I reported on my evening targets earlier in this post. The most astonishing thing there for me was a very clean split of the triple, Iota Cassiopeia – not bad for an 80mm!  This morning my first targets with the same set up included M42, M50, the Christmas Tree Cluster,  M1, plus M35.  With M35 I could also see NGC 2158, which looked a tad like M1, only smaller, though of course they are much different objects. NGC 2158 is really a star cluster much more distant than M35. Seen together the two open clusters provide a wonderful sense of depth of field.

Castor, an easy triple star, split at 72X and was much better at 100X. I also looked at Saturn, rising in the east below Leo, and was able to see Titan and one other moon.  The Leo Triplet of galaxies, M65, M66 and NGC3628, was so simple to sweep up! I just pointed the scope at Chertan, one of the stars in the triangle that marks Leo’s haunches, then slowly swept south and a tad east. Bingo – it took about 15 seconds I think. A more challenging pair were the galaxies M81 and M82. But I just remembered that, as I think Sue French once wrote, “the Great Bear has ear mites.” So I pointed the scope in the direction of his ears and prowled around. Took longer this time, but boy do these two pop in this little scope at that power. What’s more, crank up the power a bit and you can easily see that M81 is a spiral and M82 is a “cigar” with dark diagonal cloud cutting through it.

So why am I seeing the short-focal length 80mm as the Goldilocks of scopes? To summarize:

1. Portability.

2. At low power you don’t need a finder because the field is both wide and bright, a great combination.

3. While it should be obvious that larger scopes will reveal more, you can get the essential astronomy experience – the feel for a galaxy, nebula, or star cluster – with an 80mm – certainly exhaust the Messier catalog and much more, as well as split many of the best double stars and do casual viewing of planets and Moon.

And one last point on the portability front – it is short enough so that a reasonable size and weight tripod and mount, such as you have with the AstroTech Voyager, will work.  Longer scopes on this mount can put you awfully close to the ground when you’re trying to look up. With the 80mm there are no acrobatics – and no acrobatics trying to orient your eye to a finder either, since you aren’t using one!

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My Sky-Watcher 120mm ED-APO refractor arrived yesterday and I was certain I would suffer the new telescope curse of several nights of cloudy skies – and what’s more, didn’t much care!

Oh, I was anxious to see what this bargain priced “apo” could do – and hoping it would live up to it’s hype – but I’m also battling a major cold and spend most hours feeling at best half-drugged on cough medicine – at worse, looking for a firing squad to offer myself to as target practice. The forecast seemed to bear me out, but there were some question marks in it and after supper I curled up on a small couch and tried to get a little nap. This hadn’t worked for most of the day – I’d lie down and in 10 minutes be up again coughing.

But shock one – the nap worked! I didn’t wake up for two hours, felt refreshed, had missed my  dose of cough medicine by two hours and didn’t feel a need for it. I had set up the new refractor on the T-mount on the observing deck earlier in the day and left it out just in case. Well, now it was dark and I either had to bring it in, or use it if there were some holes in the clouds.  So I got dressed for outside. Checking the temperature, I saw it was 51 degrees which would seem to indicate clouds.

Nope. Shock 2:  Wonderfully – totally –  clear! Not much wind either, though that too had been in the forecast. Shock three was not so pleasant.  I gazed around trying to figure an appropriate “first light” test. I thought a good, challenging double star like Rigel would be perfect, but it was too low. So I settled on Saturn, high in the south.

Arghhhhhhhhhh! Shock three: It looked horrible! Even at low power. What was wrong with this scope! It is supposed to excel onplanets and double stars. I quickly swung it over to nearby Algieba and increased the power. This relatively easy double did split, but again, very sloppy: Like it might in the 15-inch before the mirror had cooled . . . oh my! Maybe I wasn’t quite awake. Maybe that cough medicine still had my brain sizzled. The scope’s  black tube – it has these wonderful flecks in it that sparkle in the sun – had been exposed to the sun all day. There’s a built in (not collapsible) lens shade. And, of course, I had left the lens covered until right now. Must make a wonderful little heat trap up there at the end of the tube where it can do the most damge. The lens obviously needed time to cool.

So I breathed through my nose, went back inside to make myself some tea, and came out again. It had now had 15-20 minutes to get down to air temperature. since it’s a doublet I thought that might do the trick. In any event, I swung it over to one of my favorite triples, Castor: Bingo! Charming. The seeing was nothing to write home about, but there were the nice faint diffraction rings I hoped to  see, almost kissing each other in the case of the two brighter components. (I think this was with the 13mm – 69x on this 900mm focal length. Though I’m pretty sure I jumped to the 7mm (129x) but I wasn’t taking notes.)

No – I didn’t do a formal star test. Didn’t study the image inside and outside of focus. I’ll leave that kind of hard-nosed review for another night. I wanted this to be a gala opening. I like this scope. I love the idea of having almost five inches of really fine refractor at my command without breaking the family budget. Yeah, the Chinese, I know. Hey – they are doing some real good work at incredible prices. I also like little details here – such as making the both ends of the scope white so you can see themin the dark, but leaving the bulk of it black.

This is a nice scope and it comes at a price that includes a really nice 9X50 correct image finder and what certainly seems like a very good 2-inch diagonal. (The price was $1495 and shipping was free wtih the retailer I used.) The two eyepieces included, a 20mm and a 5mm, I could do without. They seem serviceable. They may even be quite good. But I have a nearly complete set of Televue Naglers and I use a manual, alt-az mount, so I really want the wide field the Naglers provide. The eyepieces that came with the scope can wait for a more thorough evaluation another night as well.

I don’t like to bounce around a lot. I sit at the telescope and I spend time on target, but I did take a quick look at the Beehive (M44), just to experience an open star cluster. And I did stay long enough to see all four members of ADS 6921, a quadruple I’ve found a little deceiving in the past when using a good 102mm refractor. But I wanted to see how the 120ED handled a globular cluster, so I swung over to M3 and remained entranced. The seeing didn’t allow the kind of power I would have liked to use, but it was nice at about 129x.

Somewhere I found a few moments to get the 15-inch Obsession set up and the cooling fan going on it. I didn’t know how long these skies would last, but this is galaxy season and . . . so, how does this reffractor do on the Leo Triplet?

Answer? Just fine, thank you. M65 and M66 show their distinctive traits and their ghostly companion, NGC 3628 popped right out. Of the three, I have to say  NGC 3628 tends to hold my attention the longest – I guess because it plays periferal vision games with you, teasing you into wondering just how much you’re seeing.

Those three confirmed I moved on to the other “triple” in Leo – M95, M96 and M105. This is really a quadruple – or a quint – though I admit, it’s very hard to fit them all in the same field of view.  I almost always find M105 first and the reason is, it’s a double! Why didn’t Messier list it this way?

Well, maybe because Messier never listed it. It was found by his buddy Pierre Mechain, but not passed on to him for inclusion in his list. It wasn’t added to the “official” Messier catalog until 1947. But that still doesn’t answer my question. M105 has a companion that’s only about half a magnitude fainter and 8 minutes away – that’s as close or closer than a couple craters on the moon such as Plato and Copernicus –  NGC 3384.

In the new scope – as in many others, it seemed almost as bright as M105 to me, although it’s listed as half a magnitude dimmer, that’s hardly dim. What’s more, M105 is a triplet in itself with a third, much dimmer companion,  NGC 3389. And no, I didn’t see this – forgot to search for it. I was having too much fun. What I should have done is put the Clearvue 30mm eyepiece in – that would have have given me a field of more than 2.5 degrees and I at least should have captured all four galaxies in one gulp – though I’m quite sure the fifth would remain elusive at that power, though the exit pupil still would have remained well within the capabilities of my aging eyes – hmmm… really need to try this! That 30mm Clearvue was another bargain. It has a very good 80-degree afov and so should make a great, low-powered eyepiece for this scope.

But on to M51. Tonight I’m playing the tourist – hey, what’s that? What a neat double star – lavender and white. I mean, I had started at Alkaid as I do when looking for M51, but had gone in the wrong direction and ended up in the outer fringes of Bootes. What I saw, I’m sure, was Kappa Bootes and another, much wider double nearby, Iota Bootes. Don’t you love discovering stuff? Sure, I’ve seen these doubles before, but not for a long time and I couldn’t identify them until I checked the books and charts. So for a while they were my discoveries – kind of a purity there. Once you put a name to them you “tame” them – take away the wild freedom they had for a moment.

But I was looking for M51 and found it of course and was delighted to be able to detect the swirling collision that is called the “Whirlpool.” Funny how we always speak of this one as singular too, though we all know it’s two galaxies, one having passed through the other in all probability, though I can’t remember which is the bumper car and which the bumped.

I then zipped on over behind the bear’s ears to check out M81 and M82. Wow! M81 was a veritable spotlight! Yeah, I’m getting excited about this scope – and also about the night.

At this point I needed to switch to the 15-inch. Much as the 120mm was delighting me, I had just washed the mirror on the 15-inch – something I do only once a year – and I wanted to see how it was performing. Besides, the skies were offering above average transparency. At first glance I was actually a little disappointed. In a strange way I thought the view through the 120mm of M51 was better. But it isn’t. That was just a quick, first impression. As I studied M51 in the 15-inch I saw much, much more. Aperture rules. But there’s an aesthetic to the view through the 120mm that has the 15-inch beat in some ways, and there’s an ambiance – an ease – to using the smaller refractor that makes it both more intimate and more comfortabl to use.

That said – the rest of the night  I opted for just plain more – more light – which the 15-inch delivered. M81 leaped out at me, as did the dark clouds crossing M82. And I fairly danced down Markarian’s Chain in Virgo – no strain at all to see seven galaxies in a single field and if I had strained I probably would have seen a few more. But seven blows my mind – hell, one does! And I did swing back to M105 and take a quick look for NGC 3389 and found it with no problem-  the 17mm Nagler Type 4 on the 15-inch was a wonderful eyepice for this.

It was midnight by the time my cough returned – as well as some clouds – but before packing up I took one more look at Staurnt hrough the 120mm. Yep – it deserves to be called an apochromatic in myhumble opinion. Yes, if you pay $3-$5,000 more for a similar sized scope I’d expect something more – but except for the hole in my bank account I really don’t know how much difference I would notice.

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