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Rat Notes - 18" Starmaster Review / Obs Report



Editors note: Bill is a prolific contributor to the newsgroup SAA and posts under the alias "Rat" (hence the title "Rat Notes").

Anyway, things have been a little hectic, and I've been remiss in posting notes. I do plan to get back into it. Here are some long overdue notes, and a general review of the new 18" F4.3 Starmaster Dob. I am skipping over many observations for lack of time, but I'll try to do some more 'normal' reports real soon:

After four months I really feel good about choosing the Starmaster for my Big Dob. Ordered in February 2000, and delivered July 24, 2000, it is an excellent scope with wonderful design and execution, sporting killer Carl Zambuto optics. Rick Singmaster's personal service is as good as it gets. Thanks Rick! I love the new scope.

7/24/00

Got the new scope today, Rick Singmaster delivered it in person and spent an hour or so helping me set it up and get it collimated. We spent another couple of hours observing. I am going to go back through most of the list that we observed myself so I'll post the observations as I get to them. My brick telescope pad is retaining some heat and interfering a bit with the images until it cools down, I'm thinking that I will be hosing down the brick when the sun sets on telescope nights, to give it a head start.

The scope cooled down faster than the brick did. It has a 1.6" thick primary and that should help it cool down fast. Once cooled, images are extraordinary up to about 133x, at 190x they are still excellent, going to 250x was pushing it a bit for the seeing (certain objects such as Planetary Nebulae, however, seem to really like high magnification ~ 250-300x). . We discussed how seeing tends to be limited to a certain 'magnification' more so than a particular aperture. This is making sense. Around here I am typically limited to around 250x for planetary observing. I've rarely observed Jupiter at 300x to good effect.

Anyway, I am elated with the images after cool down. We collimated it right on while it was still light, right down to tweaking the secondary with the auto-collimator, which was very interesting. At F4.3 I guess it is crucial but I wonder how much trouble it is going to be to keep it there.

The eyepieces most used are the 35 Pan (65x), 22 Nagler T4 (103x), 17 Nagler T4 (133x), and 12mm Nagler T4 (188x). For higher powers I shift into the Radians - These are all used in conjunction with the Televue Parracor for edge to edge sharp fields and overall stunning views every time I look in the scope. Thank you Televue!

7/25/00

On night two, I have adjusted only the primary using one of the plastic Rigel collimating tools in the dark, which I am told, is essentially the same thing as real good eye-balling. Tonight it is working well, but not fully cooled down yet.

[11/4/00 Note:

Cool down - The scope cools down fast. Two hours seem to have it down to very steady images even with a 35 degree drop in temperature. The mirror cell is a true thing of beauty. It is wide open on both sides and with the 1.6" thick mirror, there's not much there to keep it warm. Two nights ago I had it out and within one hour I was making out a small spot in the SPR of Jupiter at 188x. Rick S. told me that night that the 80a medium blue was the filter for Jupiter and Saturn and he was right. I did have the interesting problem of the secondary frosting over one night, I took the cover off and left the scope out for three hours and the images were a bit dim and hard to focus. Leaving the cover on the secondary until time to observe has prevented this from happening again. I don't think I'll even need a dew zapper on it, as in the cold my sessions are never longer than a couple of hours. I was taken by surprise by the frost because all of my scopes have had a tube of some sort. Sure, my SCT used to freeze up good, but my 10" tube newt never has, even when it is thickly coated with frost on the outside. Just something to learn, I can just imagine what a solid tube 18" would be like. It would never cool down.

Collimation - I have checked the secondary once in the last 4 months and tweaked one knob maybe 1/20 of a turn. The rest has always been done at the primary. I was a bit worried that the plastic collimation tool that I use by Rigel Systems (5$) would not be up to the task of such a fast scope but not so at all. Each time I have used it to collimate the scope in the daytime, I have put in the Cheshire to see how well 'on' it is, and it is dead on every time! I use it at night by pointing my Rigel LED light down the tube (I have one of the red/white units), and then tweak the primary until it is centered. I have often wondered what they meant about fast scopes needing the collimation so dead on. From what I can gather, what it means is that each small movement of a collimation knob results in a large adjustment to the position of the spot in the collimating tool. I think it is the same thing with SCT's and their F2 primary mirrors. Once centered in the tool however, the thing is perfectly collimated. I guess what I am saying is that the dot doesn't have to be any better centered than in my F6 scope, its just that smaller adjustments get it there faster, so to speak.

Does it keep collimation? I roll the scope out of my shed and across about 30 feet of very bumpy and unlevel grass to get to the pad. Half of the time the collimation is still dead, dead on. I've never had to do more than tweak two knobs 1/12 of a turn to center it. Cake.

The brick telescope pad set in the grass cools down just fine when I give it a head start with the hose. It is a five- foot square of interlocking bricks, works great as a BBQ pad in the evening.]

NGC 6960 -et al - Veil Nebula - Cygnus - SNR - Well, let me just say it once: Holy Cow! We are talking Major Impressive view here. At 130x w/ the OIII filter the thing jumps out like 3D - Intertwined filaments arcing across several FOV's terminating in this big, bright and complicated, gruesome drippy thing - Wow! Don't really know what to say, that explosion must have hurt. The other, straighter half is very bright but at the same time very delicate. It looks like a long lingering layer of cigar smoke that is found floating illuminated by a lamp in a closed and smoke filled room, very 3D. Very fortunate to get such a good look at something so extraordinary in this lifetime, very fortunate indeed. This second arc fans out nicely at one end and comes to a sharp point at the other, it is illuminated by a mag~5 star near its center.

8/7/00 Moon:

Rimae Triesnecker - smallest features were 2 small ~2Km craters in a smallish branching Rima near A Hyginus. Observed the majority of the detail shown in Rukl's, also a couple of other small craters don't appear to be on the Map. When we are talking about the detail of Rimae Triesnecker, I would like to say that this is truly one of my favorite things to look at on the Moon. It consists of a beautiful criss-crossing patchwork of Rilles reminiscent of a sort of tic-tac-toe grid, beyond that a couple of them extend for a very long ways, splitting into a "Y" or two and doing some more criss-crossing. All of this is set off by small, random craters, and there are neat walls and such nearby. It is an area that a person can spend a long time being fascinated by how much like a real world the Moon is. Awesome. Just writing about it makes me want to have another look. Hate to use the cliché, but there were definitely moments when everything (the seeing) would just stop and the telescope would get out of the way, and there we'd be hovering a few miles above the Lunar surface. Unreal.

On the same kind of subject, I have given up trying to find some sort of specialty when it comes to observing. I have had some small measure of success with Lunar, Planetary and Deep Sky et al. I love Craters, cloud bands, festoons, nebulae of all designations, Rilles, rings, ovals, galaxies, clusters of all varieties, and well, you get the idea. The only thing I didn't mention was variable stars (variable stars? We don't need no stinking variable stars!) But to be honest I cannot say that I will not be giving some of the more popular ones a visit. As a matter of fact, I've already seen Mira where it was not before. There is something special about that. What I am getting at here is a lot of people start boobing when the Moon is out, why not look at the Moon? It is an endless source of observing enjoyment, as are all of the other aspects.

Also I would point out that while the image in the 18" is very bright, I have been assured that I am in no way risking my vision. This is good, because the amount of detail on the Moon in the 18" makes it well worth observing through it at full aperture. I have tried a Moon Filter and fine details visible without it became invisible with it, the quality of the filter is just not up to the quality of the rest of the system. Thanks to Carl Zambuto for making a second wonderful mirror for me (the first is an equally outstanding 10" F6, which I still use all the time).

M13 - GC - Her - In all honesty the 10" did a bang up job on almost keeping up with the 18" on the Moon. I installed a cooling fan on it around this time, and lo and behold, I've been blaming half my seeing problems on atmospherics, when in fact much of the problem has been tube currents. So much so, that I am having to reassess the seeing around here in general. This year I have been getting the best views yet of Jupiter in all of my scopes. I am thinking that part of the problem has been to do with the fact that the mirror has not been cooling down to ambient and the fact that ambient itself drops so much and so rapidly once it gets darkish. Here in the Rockies this is a fact of life, the fan has worked wonders for this aspect. I finally figured out that if I rack the focuser all the way in, I can actually see the tube currents and make an easy determination as to how bad they are. The rest of the problem (living on top of a mountain in the Rockies) I'll have to live with, but happy to say that it was not as bad as I originally thought. How long does it take to learn this hobby, anyway? Like I said, the 10" was pretty good on the Moon, but when I turned to M13, well, sorry but the 18"er left it in the dust. Don't get me wrong, I Love my 10" scope and I could easily get by with it being my only scope, but the view through the 18" is jaw dropping after looking at M13 through smaller scopes for a few years, and that's all I've really got to say about that. Except,

M57 too. I know I know, how about looking at some DSO's? Well you've got to look at the regular stuff first. And to be honest I was a bit overwhelmed with this scope in the beginning. First off, it's Big, **** Big. I have to stand on a step ladder when it's pointed high in the sky. Second, what the hell do you look at with something like that? I spent a few weeks just being lost. Before I got it I had a plan and I was doing just fine, but once I got it I was lost and my plan just kind of fell apart. That's ok, all better now. The cool thing is that the scope has these wheelbarrow handles, I just pick up one end and roll it out of this big **** shed that I own. It takes maybe 10 minutes to set everything up, and another ten minutes to put everything way. I haven't even disassembled the scope, except for the handles, once in the last four months, I can't even remember everything that Rick told me about setting it up, because I haven't done it myself yet. That's cool. I have the big blue tarp to throw over it in the shed and it is staying pretty clean. Set-up the first time was quick and easy, too. M57 is big and bright, sorry no central star yet, not steady enough seeing, but maybe one day. Lots of faint field stars, looks like a photo - another good cliché, eh?

NGC7789 - OC - Cass - This is one of the cool objects that Rick showed me the night we set it up (at least I'm pretty sure that's what it was, sure looks the same). This one should have been in Messier's catalogue, yet somehow, it wasn't. It is a beautiful rich sprinkling of faint stars in a wonderful patch of haze in my Traveler, well separated from the field of stars that it lies in. I love it. In the 18" the eyepiece is filled with a huge brilliant Open Cluster, evenly distributed and evenly bright stars, hundreds of them packed in there, wonderful. I'm sure I've recorded this one before, but I never recognized its significance. It is now one of my very favorite clusters.

Jumping ahead a bit:

8/20/00

M27 - PN - Vul - What a great object - Dumbbell Nebula - Hard to think of this one as a Planetary nebula - Bright - twin lobed - One side is brighter and denser - Several faint stars shine through this Nebula (or are superimposed). Rick S. Showed me a cool trick for finding this one: There is a semi- ringlet of stars to the side of it and all you have to do is to line the outer ring of the Telrad up with it and M27 will be centered in the FOV. Very cool.

M11- OC - Sct - Obviously another one of my faves - Extra beautiful in the 18" at 65x.

[11/6/00 - Note:

Another thing I remembered about this scope is how you can change eyepieces without the scope losing its aim. It's easy, just pop one out and pop another one in and the object is still in the field. This is going to be extra great when I get the tracking platform. ]

10/3/00-

NGC 7009 - Saturn Nebula - Aqu - PN - Small and bright - "ears' visible part of the time - Elongated oval - Very nice. 103x, 288x

NGC 7089 - M2 - GC - Aqu - This is why I do it: The eye patch, red goggles, hood, putting up with the neighbors lights, the freezing cold, the bugs, etc. M2 is so striking - at 103x it is resolved across its face with direct vision. Well, just slightly averted. The stars are absolutely pin-point - a zillion of them - so clear - the seeing is excellent up here out of the muck of the horizon, and after 90 minutes the scope is well cooled. 103x shows a stronger, hazy extended background, at 188x the glob was perfectly steady - big bright packed with stars on a bright round haze - Excellent - went back to 103x for perspective, simply excellent again! 103x, 133x, 188x - Seeing and transparency help a lot when it comes to observing these objects.

NGC 7078 - M15 - GC - Peg - Could this one be even better? Geez! More condensed center - Star trails everywhere - Large, resolved to the core, 2 bright stars in center - Truly amazing, these are two of my faves - 103x, 133x, 188x

Well, you get the idea: What a great scope!

M31 becomes an object for an evening's viewing. NGC 206 to the end of M31, with enough mass to be a galaxy itself. Two stark dust lanes on the side of the M31 with another one on the end near NGC 206, as well as the two companions - M32 with its stellar core and round extended halo and NGC 205, a very nice, bright oval ball of fuzz. Wow!

M33: a huge face on spiral that has more HII regions with their own NGC designations and such, showing as brightly as galaxies on their own. Simply awesome, I want to stare at M33 for hours.

And a couple of nights ago -

11/3/00

Abel 426 - Perseus Galaxy Cluster - The transparency in my back yard has been going downhill for some years now. Still, around Polaris, mag 5.8 stars are visible, so from my back yard it is still pretty easy to observe some fairly faint objects. One of these has been Stephan's Quintet. I have found the quintet with ease in the 18" but have not yet made a proper dark adapted observation. I did attempt to get a look at Abel 426 the other night. I was able to end up seeing a parallelogram of four galaxies, one of the four was actually a pair, so five galaxies in a clump in the center of the cluster. They were NGC 1275 - the brightest - round - NGC 1272 - 2nd brightest - still roundish - NGC's 1277-8 and NGC 1274 all somewhat fainter and the pair 77-8 more elongated. Also somewhat to the South NGC 1282 was observed, which was actually quite faint, pretty much at the limit of the magnification that I was using.

[Note: Which brings me to another point: None of these galaxies were even faintly visible at 65x. Only by scanning for them at 133x did they pop into view, which is another reason why I expect tracking to be a big help. I think that once I am in the 200-250x range looking for these faint objects, even more of them are going to start popping into view. I'm sure that this is a region that I will be visiting again in hopes of catching some more, fainter galaxies.]

Same night -

Jupiter - 188x - Nice - I've learned the value of using filters and tonight I was able to quickly make out a couple of spots - one dark and one light - in the SPR preceding the GRS - Great! Also there was a big, long, thin festoon on the CM at the same time, bisecting the EZ on about a 45 degree angle. I wish I had better seeing, but just the same this was after only an hour of cool down and I really can't complain. I really can't complain…

I'm going to keep track of which scopes get used when, but its looking like all of them have a place. The 18" will probably get used most on Moon-less nights, the 10" is a great all purpose scope that does a wonderful job on the Moon and Planets. The Traveler only needs about an hour's worth of observing time to make it worthwhile to set up, and all objects are a joy to observe with it. And the Ranger is going to get set up today on the video tripod as the true "eyepieces in the pocket" - quick look scope. Add to that the 7x50 binos, and I think I only need about one more telescope to have a complete collection. Or, maybe two…

Anyway, that's about it for now. I'll try to keep up with the notes a little better. This one has been due for a while and I wanted to let everyone know what a truly great scope the Starmaster is.



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