The Battle of the Mighty Mites
Celestron 80 WA vs. Orion XT 4.5 vs. Orion Starblast
With a start I awoke from another trance induced by staring into the Astromart classifieds. Egads! I had just bought another telescope! Now what was I going to do? My stable of small telescopes had just gone from two to three (okay, actually four to five - but let’s not have any distractions from other telescopes who don’t appear in the story). Would my Orion XT 4.5 be jealous of the newcomer? Its place as the most used small telescope might be threatened by the sporty green newcomer and its 4.5" mirror. And what about my grizzled “old” Celestron 80 EQ WA? With a focal length of 400mm it was King of the Richfield. Would this be threatened by a scope with more aperture and an f/4 ratio? All I could see was trouble ahead from buying the Orion Starblast and having my sleep disturbed by small telescopes arguing in the night about which was best. No, better to have it out NOW. A good clean contest between the three of them. A Battle of the Mighty Mites.
A Mighty Mite is a telescope that is portable enough to be carried in one hand, cheap enough to cost less than a premium eyepiece, and capable enough to provide nice views of a wide variety of celestial objects. Here are the basics of my three.
The Celestron 80 WA EQ is an 80mm f/5 achromatic refractor. The OTA is mounted on a small EQ mount. This particular telescope is no longer widely available, but the OTA is the same as the Orion ShortTube 80. The entire rig weighs 13 pounds. A similar rig, the Orion ShortTube 80mm EQ refractor sells for $279 and the OTA sells for $199. Note that I replaced the stock diagonal with an Orion Mirror Star diagonal.
The Orion XT 4.5 is a 4.5" f/8 newtonian that is dobsonian mounted. This telescope has a spherical mirror. It weighs 17.5 pounds. The XT 4.5 sells for $199, including two decent plossel eyepieces.
The Orion Starblast is a 4.5" f/4 parabolic mirrored newtonian that is mounted on a modified dobsonian mount. The azimuth is what you would expect but the altitude features a single arm support with a variable tension knob and ball bearings. It weighs 13 pounds. The Starblast sells for $169 including two inexpensive Explorer eyepieces (I do not own these eyepieces).
I have been actively observing for the last six years. My interests have been visual only, all types of objects. I believe my observation skills are average.
My front yard was the best place for me to haul three scopes out at a moments notice when the clouds break and start observing. So the observing conditions would include good transparency, fair to poor seeing that is common at this time of year, and a large amount of light from the neighbors and a nearby street light. The limiting magnitude was generally about 5.0 to 5.5 from this location.
By using the same eyepieces I could eliminate one variable - the effect of the eyepiece. Since the XT had twice the focal length of the Starblast a good 2x barlow made same magnification comparisons possible. I settled on using a 25mm and a 9mm Astrola fully multi-coated plossels that the previous Starblast owner had used to replace its stock eyepieces. I suspect any good plossel would have done equally well. For a barlow I had an Orion 2x Super Shorty. These give the following magnifications:
80 WA: 16x, 32x, 44x, 89x
Starblast: 18x, 36x, 50x, 100x
XT 4.5: 36x, 72x, 100x, 200x
By comparing each scope against the other on the same target at the same time effects such as seeing, transparency, and limiting magnitude would also be eliminated or at least reduced. The grading system would be simple and based on my perception of the quality of the view: A = very good; B = good; C = fair; D = poor; F = very poor. Plus and minus grades would be allowed (i.e., B+).
The telescope that was best on the most targets would be the winner.
All I had to do now was wait for clear skies. Surprisingly they arrived a few short days. The battle had begun! It would rage when weather permitted for approximately fifteen hours spread over the next few weeks.
Starblast and XT at 100x: Concentrating on area around Copernicus, I look for small surface features in all three scopes. My first surprise is that with a lot of switching back and forth the views in the XT and Starblast are essentially the same. The smallest details I pick out in one I can see in the other.
80 WA at 89x: definite lime green line along limb of Moon. It tends to go away when you look at it and is only a minor distraction. The short tube’s views are almost as good, but after switching back and forth for an hour I decide I prefer the sharpness, detail, and lack of chromatic aberration of the Netwonians.
Note: Later using non-test eyepieces I push the Starblast and XT to 134x, the highest magnification my eyepieces would give for the Starblast, both views looked fine.
MOON GRADES:..........80 WA: B+..........XT 4.5: A..........Starblast: A
Starblast and XT at 100x: First evening of bad seeing Cassini division only hinted at during better moments. On the second night of better seeing Cassini’s division seen all the way around Saturn. It was not a sharp dark line but it was steady and hints of banding were seen on Saturn’s surface. Again views through the two telescopes were indistinguishable to me. Nice view!
80 WA at 89x: First evening of bad seeing Cassini division only hinted at during better moments. The Newtonians were doing better than the refractor but none were especially impressive. Second evening of better seeing focus was trickier than the other two scopes and the view was not as crisp. Hints of banding were very fleeting and not nearly as directly seen as in Newtonians. Cassini’s division was apparent but fuzzier.
SATURN GRADES:..........80 WA: B..........XT 4.5: A-..........Starblast: A-
Starblast and XT at 100x: Two distinct bands seen with shading on both poles, some variation in banding but not much. Three moons were present, different sizes, strung out on one side. I finally see the moon shadow on one of the bands very close to the limb. It isn’t very steady and it isn’t perfectly round, but its definitely a shadow transit. The views are very close in both scopes.
XT at 200x: The shadow shows clearly, a black dot on one of the bands very close to the limb. The dot is much more steady and round. The view at 200x in the XT is the best.
80 WA at 89x: Jupiter was lime green with purple bands! A purple corona surrounded the planet. This was not subtle. Two bands were present and the same shading at the poles. No shadow transit seen.
JUPITER GRADES:..........80 WA: D+..........XT 4.5: B+..........Starblast: B
Castor is a lovely double star with components of nearly equal magnitude separated by 3.8".
Starblast at 100x: Definite split, the components seemed to touch each other with a bit of black separation coming and going. The difference in the star’s magnitude is obvious. Nice!
XT at 100x: Same view as Starblast.
XT at 200x: Split in the XT is much better, the black between the stars is solid, the primaries are bight and the diffraction rings of the two stars touch. Very nice.
80 WA at 89x: The view is much dimmer. The split, however, is cleaner than the newtonians at 100x. The black space between stars is steady. However, the stars are definitely lime green! I didn’t like the green but thought the split was pretty nice. The XT’s view at 200x was definitely best.
CASTOR GRADES:..........80 WA: B+..........XT 4.5: A-..........Starblast: B
Polaris is a double star with a secondary seven magnitudes fainter than the primary. The separation is a wide 17.8".
Starblast and XT at 100x: Polaris was a bright white star in both scopes, albeit a little fuzzy. Its companion was a steady white dot, extremely faint, not easy to hold but steady. The separation was quite wide. It was a nice split.
80 WA at 89x: Polaris was a yellowish green color, very fuzzy and hard to focus. The companion eluded me for some time. Finally I began to see it in glimpses. It was much less steady but I’m sure I was seeing it.
GRADES POLARIS:..........80 WA: C+..........XT 4.5: A-..........Starblast: A-
Being a large diffuse target, Andromeda seemed like a good target for the rich field scopes.
Starblast at 18x: FOV looked nice, encompassing what was visible of the galaxy and a lot of black space around it. A bright central core visible with a fuzzy indistinct halo - not really that much detail. M110 was detected but not easily visible.
80 WA at 16x: I found the view looked very similar except the stars were more pin point and a bit dimmer. M110 detected. It was very close.
XT at 38x: A somewhat tight view with Andromeda that looked really quite nice - this was actually a good magnification for a close up. Much brighter but again not a lot of detail.
Starblast at 50x: This view was pretty tight and quite bright, the condensed core surrounded by haze.
80 WA at 48x: This view is somewhat dimmer than the Starblast. Switching back and forth between the scopes I really didn’t see all that much difference other than brightness.
Note: None of the views really show a clear delineation between dark space and a galaxy. I’m not sure where the galaxy begins and where it ends. Finally I judge the Starblast best because its wide field and brightness. The 80 WA’s faintness is offset by a slightly crisper field and its wide field ability.
M31 GRADES:..........80 WA: B..........XT 4.5: B..........Starblast: B+
Starblast and XT at 36x: The perfect framing for this target. The view is surprisingly good. I believe I saw hints of detail and mottling in M82. M81 was shaped like a small tilted lens with a well defined nucleus. The star field was dotted with bright, well defined stars.
80 WA at 32x: The same shape is seen in the galaxies but there seemed to be less detail and the view was dimmer. Also, the star field was not as interesting.
M81/M82 GRADES:..........80 WA: B..........XT 4.5: A-..........Starblast: A-
NEBULA AND CLUSTERS
Starblast and XT at 50x: The views in the two scopes are the same. The four stars of the Trapezium are seen with difficulty. The nebula looks good but I think we can push the magnification.
Starblast and XT at 100x: Again views are essentially identical. The four stars of the Trapezium are now easily resolved and significant detail is evident in the nebula. A very nice view.
80 WA at 89x: The nebula does not seem to be quite as extended as in the other two telescopes. However, the contrast was slightly higher that the Newtonians and detail in the nebula is quite apparent. The stars were tighter pin points and the Trapezium resolved into a small trapezoid with beautiful stars of different sizes. I feel like I could have looked for the E and F stars with some chance of success. Overall, the view was very nice - and superior - to me.
M42 GRADES:..........80 WA: A..........XT 4.5: A-..........Starblast: A-
The Pleiades is another extended target that should suit the Starblast and 80 WA.
Starblast at 18x: The Pleiades are framed nicely. However, compared to the 80 WA the field is clearly not as flat. It seemed like space was stretched over a very shallow upside down dish. Stars in the center of field were mostly focused but degraded toward the edge of the field. With many bright stars taking up most of the field the effect is more pronounced than I’ve seen before.
80 WA at 16x: The field is flat and the stars are sharp and pin point. The seven sisters are noticeably brighter than the rest, and looked like a mini-Big Dipper asterism in a rich star field. The view is not as bright as the Starblast but the number of stars seems to be about the same. The view is very nice.
XT at 36x: The view looks good but only shows a portion of the Pleiades. The context is lost.
M45 GRADES:..........80 WA: A ..........XT 4.5: C+..........Starblast: B+
80 WA at 16x: The double cluster was almost lost among the rich star field.
Starblast at 18x: The double cluster was brighter and denser than in the 80 WA and stood out more. The view was slightly more pleasing.
Starblast at 38x: The double cluster is perfectly framed. The field is filled with stars and it’s a very good view. However, I note that compared to the XT at the same power the edge of field seems a little soft - perhaps the 25mm Plossel does not barlow as well as the 9mm?
XT at 38x: Perfectly framed, great view, like many small diamonds on velvet - very rich. Slightly better than the Starblast.
80 WA at 32x: Switching back and forth between all scopes I do note the stars in the 80 WA are slightly tighter looking, as usual. However the view looks a little sparse compared to the other two scopes. A noticeable difference in the number of stars and the overall effect is just not as pleasing.
DOUBLE CLUSTER GRADES:..........80 WA: B+..........XT 4.5: A..........Starblast: A-
SUMMARY OF TESTS
MOON:.................................80 WA: B+..........XT 4.5: A...........Starblast: A
SATURN:..............................80 WA: B.............XT 4.5: A-.........Starblast: A-
JUPITER:..............................80 WA: D+..........XT 4.5: B+.........Starblast: B
CASTOR:..............................80 WA: B+..........XT 4.5: A-..........Starblast: B
POLARIS:.............................80 WA: C+..........XT 4.5: A-..........Starblast: A-
ANDROMEDA:.......................80 WA: B............XT 4.5: B............Starblast: B+
M81/M82:............................80 WA: B............XT 4.5: A-...........Starblast: A-
ORION NEBULA:...................80 WA: A............XT 4.5: A-..........Starblast: A-
PLEIADES:...........................80 WA: A ...........XT 4.5: C+..........Starblast: B+
DOUBLE CLUSTER:...............80 WA: B+..........XT 4.5: A............Starblast: A-
In the following sections I will attempt to briefly summarize my opinions of the three telescopes based on the contest.
CELESTRON 80 WA EQ
Mechanically the EQ mount is rock solid with this OTA. I suspect the same would be true of any decent small GEM. Locating and tracking objects is very easy with this rig except when the target is near Polaris or zenith. This is a function of the equatorial mount and not the OTA. I personally find the EQ mount a slightly less portable and easy to use than the dobsonians. Overall the OTA features very solid construction that I find very close to an older Vixen OTA I own.
Optically the 80 WA was clearly the underdog. Aperture wins, doesn’t it? And with 3.1" against 4.5", the 80 WA was outgunned. Nevertheless, it managed to pull out two wins out of ten targets. The deciding factor in both cases was how nice the stars looked in a refractor. The targets in both cases weren’t too bright or didn’t include a lot of faint stars. If the object were too bright chromatic aberration would start to become distracting. If the object were too faint than the 80's modest aperture would show fewer stars and dimmer views. But for some objects in the middle it is “just right.”
In the overall contest the 80 WA finished well behind its two other adversaries. However, part of this battle was also to determine if the 80 WA could hang onto its title of “King of the Richfield.” If the planets and double stars are not considered, the contest between the Starblast and the 80 WA is too close to call. Rather than declare an outright winner I’ll just call them both “good - but different” when it comes to richfield.
Mechanically, the design of the Starblast is very well thought out and the construction is solid. It looks like it will stand up to years of use. I preferred finding objects with this scope due to the unit finder/wide field combination - but that may be personal preference. Tracking was smooth and I liked the adjustable tension knob and ball bearings in the altitude movement. The only real downside is finding something to put the telescope on. I did not find collimating the telescope difficult. I simply read the directions, and, using the peep hole sight device was satisfied with the results in three minutes. I think the Starblast is an attractive scope with curved styling and a green tube that may appeal to some people more than the functional form-factor of the XT.
Optically the Orion Starblast strikes me as a scope that aspires to be slightly more capable than the XT 4.5. However, like an aspiring child who needs an Ivy League education to fulfill his or her potential, the Starblast’s f/4 parabolic mirror needs expensive eyepieces to be at its absolute best. I’ve read this scope can give good views at 50x per inch - 225x. Just coming up with a set of eyepieces that will take advantage of its wide field ability and give high magnifications all in a focal length of 450mm is an interesting challenge. I was impressed by how often its views were identical to the XT at the same magnification. And, although the Starblast must have shown significant coma, I found it objectionable only on one target.
In the Battle of the Mighty Mites the Starblast was best in five out of ten targets, one of them outright, and came in second. Its losses to the XT always seemed to be due to some shortcoming of eyepieces - not enough magnification or an eyepiece that didn’t barlow well. It never gave me less than a “B” view of any object.
ORION XT 4.5
Mechanically the XT design is functional above all else - and I mean that in a positive way. Construction is solid and durable. The handle on the OTA makes it super portable. The correct image finder works well. Every element of the telescope seems balanced. The one minor criticism I have of this telescope is its movements, especially in altitude. They are somewhat stiff - the springs seem too tight. At least one quick fix has been posted on the Internet, however.
Optically the combination of a 4.5" mirror and long focal length provide good views on every target. The 900mm focal length gives it an impressive range of magnifications which came in very handy when splitting double stars and catching additional detail on planets. I was impressed by the fact that every time I looked through the eyepiece the view looked good. There was no chromatic aberration and no coma or curvature of field.
The XT 4.5 won the Battle of the Mighty Mites by being best on seven of ten targets, three of them outright. It was a close contest though. With more expensive eyepieces the Starblast might have been the winner due to its rich field ability. But that would be a different contest. This time the XT 4.5 showed that with eyepieces similar to what it comes with and a barlow it was the best all around telescope.
This concludes the Battle of the Mighty Mites. I believe all the telescopes acquitted themselves quite admirably. What does the future hold for these telescopes? Well, I believe the 80 WA OTA will soon be mounted atop my LX 90. This seems like a great combination. The XT 4.5 and Starblast will, I think, get frequent use from my children and me. The XT 4.5 and Starblast seem to be a bit like the characters in the movie “Twins,” very different on the outside but closely related on the inside.
Thanks for taking the time to read this!
Click here for more about the Orion Starblast. -Ed.
Click here for more about the Orion XT 4.5. -Ed.
Click here for more about the Orion Short Tube 80 and EQ mount. -Ed.
|All times are in (GMT-8:00) Pacific Standard Time Zone|
|Astronomy News | Telecope Classifieds | Telescope Auctions | Telescope Reviews | Telescopes | Telescope and Astronomy Forums | My Account | Help | RSS|