Jeremy's almost but not quite entirely moribund blog

Saturday, January 21, 2006

Review - Meade Telestar 60AZ-A2

Why is it that when someone says "Don't touch that; it's hot", we always have to find out for ourselves and end up getting burned? I'm an astronomy newbie. I've had 10x50 binoculars for several months and I bought my first telescope a few weeks ago--an Orion StarBlast 4.5 EQ. This review is about my second telescope, an impulse buy, a cheap 60mm department store refractor. I'd read in many "first scope" guides to stay away from department store scopes and that cheap scopes do more to kill the hobby than promote it. So when I saw the Meade Telestar 60AZ on the shelf for $39.95, I had to see what all the fuss was about. At least this scope has a well-known brand name and it doesn't advertise ridiculous magnification levels on the box. And it comes with two 1.25" eyepieces too.

My "real" telescope, the StarBlast 4.5 EQ, is reasonably portable, but not as "grab and go" as I would have liked. The mount is a bit awkward and doesn't collapse well for travel. I thought the Telestar would be easier to toss in the trunk and take camping or whip out at a moment's notice to catch a glimpse at, say, Saturn poking through the clouds. Or set up alongside my "real" scope to let my 3-year-old daughter look at the moon through a conveniently located eyepiece. Also, I could see if my Expanse eyepieces would help it out any, and I could try out its eyepieces in my StarBlast and get a few new magnification levels out of it. Also, with its alt-az mount and right-side-up (but horizontally flipped) image, it'd make a better terrestrial scope than my StarBlast.

So I assembled the Telestar and took it outside. Although it had been cloudy most of the day, it was clear at night (the telescope gods smiled upon me a second time!), so I set it up next to my StarBlast and did some comparative observation.

The first thing I discovered was that the Telestar's mount fully lives up to the reputation of department store telescope mounts. The slightest touch sets the scope vibrating for 5 seconds or more, compared to the StarBlast's EQ-1 which damps out in 2 seconds or less. Also, the Telestar's altitude adjustment doesn't work well--it slips easily and its slow motion knob is unsteady. Once I got the scope pointed at my target and tightened the knobs, it held its position reasonably well, but it's hard to adjust. That's one reason the Telestar works best with low magnifications--you won't have to adjust the scope as often. (Another reason is of course its small 60mm aperture...)

I don't care for the 5x24 finder scope, which has extremely narrow eye relief and is set up for the right eye, whereas my left eye is dominant. It's also a pain to align accurately. The red-dot reflex sight that came with my StarBlast is much easier to align and use.

Although the mount and finder leave something to be desired, the scope's optics are actually pretty decent. The objective is a 60mm fully-coated achromatic. Focal length is 700mm. Two eyepieces are included, Meade MA25mm and MH9mm. According to the eyepiece buyer's guide on this forum, those letters stand for Modified Achromatic (fully coated Kellner) and Modified Huygenian. The 25mm eyepiece is sharp and clear (to my inexperienced eyes at least), but has a pretty narrow field of view. The 9mm eyepiece is a bit fuzzy and has poor eye relief, but what can you expect when you could easily spend several times the cost of the whole telescope on one good eyepiece.

My first target was the bright 16-day-old Moon. I was impressed with the clarity and detail I saw through the 25mm eyepiece--I'd say it rivaled the view through the StarBlast. Even at 9mm, I was hard pressed to call one scope's view better than the other's. Neither of my telescopes is suitable for high magnification, so I can't comment on that, but for observing the whole disc of the moon, the Telstar does a decent job.

Next, I pointed at Saturn. It was tiny but sharp at 28x, and at 78x, the rings were clearly visible. I didn't notice offensive color fringing. Again, the view was comparable to my StarBlast (although my StarBlast was much easier to point at Saturn and keep there). Next, I popped in the 2x Barlow that came with the Telestar. I was not surprised that the results were a dim, blurry mess--156x is too much for a 60mm scope. Which is just as well, because the included Barlow is 100% plastic (including the lens). Even in my StarBlast, the Barlow does nothing but add psychedelic color fringing.

My next target was M45, the Pleiades, which was near the zenith and quite difficult to point the Telestar at. I had to lie down on the ground to get my eye under the finder scope, and the finder's field of view is so small that the Pleiades fill it entirely. The view through the scope's 25mm eyepiece was an improvement over my 10x50 binoculars at least in terms of how many stars I could see, but I couldn't see the whole cluster at once. The StarBlast provided a wider, brighter, much more satisfying view.

I decided to check out M42, the Orion Nebula, next. Here again the StarBlast wins hands-down. With the Telestar, I could make out the dim outline of the brighter part of the nebula. It was more than I could see through my 10x50s. But it was not as grand as what I could see through the StarBlast, with which I easily resolved the stars in Trapezium. They all blurred together in the Telestar. [UPDATE: On a night of good seeing I could resolve Trapezium easily with the Telestar.]

The bottom line? This department store scope provides serviceable optics for the moon and other bright objects at a very low price, but it's held back by an unsatisfactory mount. If the mount worked better, I'd feel comfortable suggesting it to friends who have a passing interest in astronomy but don't want to spend hundreds of dollars on a "real" telescope just yet. But this scope is difficult enough to point at a target and keep steadily there that I understand why people say department store scopes can frustrate beginners and be harmful to the hobby.

UPDATE: I've had this scope for a few weeks now. It doesn't get used as often as my StarBlast, but I've found that its mount is almost tolerable if you tighten everything up often. It also works better with my Expanse eyepieces (the ones that came with my StarBlast)--they're heavier than the half-plastic included eyepieces, and they make the scope less top-heavy.

Here's a picture of the Moon I took through this scope and its 25mm eyepiece:

Friday, January 06, 2006

Review - Orion Starblast 4.5EQ Telescope

Well, I finally took the plunge and bought a telescope--an Orion Starblast 4.5EQ. This scope combines the tube from Orion's famous Starblast Astro "mini-Dob" with an EQ-1 equatorial mount, and it also upgrades the eyepieces to the "Expanse" line to take better advantage of the scope's wide field ability.

I figured the scope would be a good compromise between aperture and portability--big enough to let me see some deep space objects, but small enough to pack along on our family trips out to the country. And the tube is just about the right size, but the mount is bulky and awkward and doesn't collapse well, so it remains to be seen if I'll be able to fit it into our compact car with all the kids and stuff. I might have to partially disassemble it to do it.

Speaking of assembly, the manual is a little inadequate. Assembly instructions are a little vague, referring to several parts by name without clearly identifying them. There is a picture, but it has a dozen arrows pointing at it and it isn't clear what's what. Also, the packaging must have changed somewhat since the manual was printed, because several parts weren't where the manual said they were. For instance, the manual said to remove the bolts from the tripod legs, install the legs on the mount, and then replace the bolts--but the bolts weren't on the tripod legs to begin with. They were in a little bag.

Once I found all the parts and made sense of the instructions, though, everything went together well. The mount operates smoothly and seems reasonably sturdy. The slow-motion controls make it quite easy to center the target in the eyepiece. I just have one complaint about the mechanical operation of the mount: the counterweight shaft gets in the way of the right ascension cable fairly often. Speaking of which, the R.A. cable can be attached on either side of the mount--"whichever is most convenient", the manual says, which can be translated as "you'll find yourself moving it from one side to the other several times per night (don't drop the thumbscrew in the grass)". With the scope pointed south, I have to disconnect the cable entirely because it's blocked on one side by the counterweight and on the other by the OTA. Maybe I should have just gotten a Dob. ;)

Enough about the mechanics; it's time to talk about the optics. Fortunately, the telescope gods smiled upon me and I was blessed with clear skies the first two nights after my scope arrived. (Tonight, the third night, is cloudy, which is why I'm typing this review instead of looking at the stars.) This is my first telescope, so I don't have much of a frame of reference to compare it to other than my $30 Simmons 10x50 binoculars (which, though cheap, were great for introducing me to the sky, although difficult to hold steady).

The Starblast 4.5EQ comes with two eyepieces, a 15mm and a 6mm Expanse (mine are actually labeled Ultrawide, but I've read they're the same thing). In conjunction with the 450mm focal length of the scope, these yield 30x and 75x magnification, respectively. Eye relief is good--I can look through either eyepiece with my glasses on and see a wide field. The 6mm EP is prone to "blackouts" if I'm not looking directly into it, though.

The first target I pointed at (after my abortive attempt at polar alignment) was the waxing crescent Moon. It was stunning! The clarity and contrast blow away anything I've seen before. Mountains and craters popped out with stark relief. I might have to invest in a lunar filter, though, since even at about 1/3 full, it was uncomfortably bright.

Next on my tour was the Pleiades. They took a bit of effort to find, but once I did, I wasn't disappointed. I didn't see any nebulosity (I imagine I'd have to go to a dark sky site) but I did see an awful lot of stars--many more than I could see through binoculars.

I swung around to the Orion Nebula and the view was quite nice. The small white fuzzy blob I remember seeing in my binoculars was... well, a bigger fuzzy white blob, but a very pretty one. I could make out the shape pretty well, but I knew enough not to expect to be able to see colors like you see in long exposure astrophotos.

About this time I realized Saturn was up, so I took a look. I was a little disappointed--Saturn was miniscule. Switching to the 6mm eyepiece upgraded it to maybe just tiny. Before I bought the scope, I read a review where someone wrote that the Cassini division was easily visible. I'm guessing he used a much nicer eyepiece than the stock units and/or a Barlow. I couldn't see the Cassini division at all, although I could easily see the gap between the planet and its rings. I'm not sure how many of Saturn's moons, if any, were visible, because I was too busy staring at the rings to look for them. To be fair, the seeing wasn't very good--Saturn visibly shimmered at 75x, so maybe the Cassini division would be visible under better circumstances. I'm tempted to get a 2x Barlow to help things out a bit.

Early the next morning, I took my scope out and looked at rising Jupiter. The four Galilean moons were easily visible. No surprise there, since I could see those just fine with my binoculars (assuming I could hold them steady enough). Jupiter itself was a featureless white disc for the most part, but I think I caught a fleeting glimpse of the cloud bands once or twice.

Next I decided to point at the Mizar/Alcor double in Ursa Major. I remembered reading that Mizar itself is a double, and I wondered if I'd be able to see it. The answer is: yes, easily. Comparing what I could see with the Starry Night software, I found that 10th magnitude stars were visible.

I have yet to catch Venus--it's pretty low in the sky now, so I might not be able to see it for a few months. I almost saw it yesterday evening, but it ducked behind clouds just as I found a line of sight between the trees, houses, and power lines.

Perhaps tomorrow I'll look at snowcapped Mt. Timpanogos and see how my scope performs on terrestrial objects. Upside down, obviously, but my real intent is to get the finder scope aligned properly by pointing it at something that doesn't move. It's been a little touch-and-go thus far, as I've had to hunt a bit before I could bring what the red dot pointed at into the eyepiece.

All in all, I'm happy with my new scope. The mount is a little awkward, but works smoothly (when the counterweight shaft doesn't interfere with the R.A. cable, anyway). It's not quite as portable as I'd hoped, but it's not too unweildy either. I'm no expert, but the optics look great to me. The moon is spectacular. Stars are crisp and bright. The focus is a little touchy, though--it can be difficult to get the image just right. The wide field view takes in a lot of sky, which is nice for deep sky objects (can't wait to see Andromeda from a dark sky through this scope) but not ideal for planets.

UPDATE - Feb. 8 2005

I've had the scope for over a month now. I still take it out just about every clear night (and many clear mornings). I got an Orion Shorty 2x Barlow, and that helps with lunar/planetary viewing. Some new observations:

  • Jupiter - I could see four cloud bands pretty well. The Galilean moons are, of course, easily visible, though they appear starlike (I can't resolve them into discs).
  • Mars - I got my scope too late for the opposition. Mars is just a little orange ball, but I think I might have glimpsed Syrtis Major.
  • Saturn - On a night of good seeing, I could easily resolve the Cassini division. I even dragged my wife out and she saw it too. It was visible even without my Barlow (at 75x).
  • Venus - Seen as a beautiful crescent in the early morning sky.
  • Andromeda Galaxy - I could only see a faint smudge of light, but I haven't had the chance to see it from a dark sky site yet. My best view of the galaxy still belongs to my 10x50 binoculars.
  • Orion Nebula - Recognizeably the same thing as you see in astrophotos, though faint, colorless, and not as expansive. The four stars in Trapezium resolved nicely.
  • The Moon - This telescope has unfolded a whole world up there! With good atmospheric conditions, the scope provides crisp, bright views at 150x that make it look almost like you're peering through the window of the Apollo CSM. Mountains, "seas", and countless craters just pop out at you.

    Here's a photo I took through the eyepiece: