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Equipment review
Orion’s StarBlast 6 makes a great first scope This grab-and-go telescope offers 6 inches of light-gathering in a compact design. by Glenn Chaple
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n 2003, California-based Orion Telescopes and Binoculars introduced the StarBlast, a 4.5-inch Newtonian reflector designed mainly for kids. The StarBlast caught on with adults as well, from novices looking for a user friendly first scope to veterans wanting something portable. (See “Orion’s StarBlast” in the January 2004 issue of Astronomy.) The “Little Scope That Could” proved to be such a success that Orion decided to give it a big brother. Enter the new StarBlast 6. In creating this telescope, Orion didn’t have to invest a lot in development. The This telescope is a Newtonian reflector. Its mirror measures 5.9 inches (150 millimeters) in diameter, and, from a dark site, will show you stars as faint as magnitude 13.6.
company took the tube assembly from its Astroview 6, a 5.9-inch (150 millimeters) f/5 rich-field reflector, and placed it on a scaled-up version of the original StarBlast mount. Orion replaced the Astroview’s 6x30 optical finder with a less costly reddot reflex sight and added a navigation knob to the tube’s front. Too bad Orion didn’t go with the eye-pleasing teal color found on the original StarBlast tube. That would allow for a family to have a matching pair of parent and child StarBlasts.
Setup and operation Those who dread assembly projects that take hours and require a workshop full of tools will appreciate the StarBlast 6. Because the base comes already assembled, you need only attach a pair of mounting rings to it (with the supplied Allen wrench), clamp the tube in the rings, and add the finder and the eyepiece tray. You’ll need a Phillips-head screwdriver for the latter. Complete assembly takes about a half hour. Close inspection showed that the optical alignment was slightly off right out of the box. This wouldn’t hinder general use, but it could compromise high-power images. Thanks to clearly written and illustrated instructions in the user manual and a supplied collimation cap, fine-tuning the alignment was easy. The StarBlast 6’s short tube also let me adjust the primary mirror while peering
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Specifications Orion’s StarBlast 6 Type: Newtonian reflector Mount: Modified Dobsonian Primary mirror: 5.9 inches (150mm) Focal length: 750mm Focal ratio: f/5 Focuser: 11⁄4" rack-and-pinion Finder: EZ Finder II red-dot reflex sight Eyepieces: 25mm (30x) and 10mm (75x) Sirius Plössl eyepieces Total weight: 23.5 pounds (10.7 kg) Included: 25mm (30x) and 10mm (75x) Sirius Plössl eyepieces, collimation cap, Starry Night special edition desktop planetarium Price: $249.95
through the collimation cap. In a matter of minutes, the scope was ready. Because the eyepiece of the StarBlast 6 is never higher than 28 inches (71 centimeters) above the ground, using this scope brought me to my knees — literally. Orion recommends placing the instrument on a sturdy table or car hood. I opted for the table. While the mount is steady (vibrations ceased within seconds of my tapping the tube), it’s at the mercy of the platform chosen to elevate it. Like the original StarBlast, Orion’s StarBlast 6 is user friendly. Lightweight (23.5 pounds [10.7 kilograms]) and furnished with hand grips cut into the base, it transports easily. Teflon bearings and Glenn Chaple is a contributing editor of Astronomy who writes the “Observing Basics” column each month.
All photos: Astronomy: William Zuback
an adjustable tension knob permit smooth side-to-side (azimuth) and upand-down (altitude) motion. Two eyepieces, 25mm and 10mm Orion Sirius Plössls, yield magnifications of 30x and 75x, respectively. I used the former, with its 1.7° field of view, primarily as a search eyepiece for sky objects I targeted with the red-dot finder. The 10mm Plössl generated the magnification a novice might want. The Moon, Saturn, Jupiter, and bright double stars like Mizar and Albireo all presented themselves well through this eyepiece. Would the StarBlast 6 satisfy the demands of the seasoned amateur astronomer? Its portability certainly wins points. The fully assembled scope fit nicely in the passenger seat of my car. For
Background image: Daniel B. Phillips
Orion’s StarBlast 6 combines good optics with easy portability. The optical tube attaches to an alt-azimuth mount. The EZ Finder II sits next to the focuser.
lengthy excursions, I’d suggest removing the optical tube assembly and securing it in a protective case.
Targeting the sky The 75x provided by the 10mm Plössl was fine for general sightseeing, but I wanted to see detail only higher magnification could provide. The Hercules Cluster (M13) is a case in point. Through the 10mm Plössl, this globular cluster was resolved but appeared smaller than I would have liked. Doubling the magnification with a 2x Barlow lens not only enlarged the image but also increased the contrast, transforming M13 into a teeming stellar mass. The Barlow boost also improved views of the Ring Nebula (M57), the Whirlpool Galaxy (M51), Bode’s Galaxy (M81), and the Cigar Galaxy (M82). A single observation of the “Double Double” (Epsilon [ε] Lyrae) quickly erased any doubts I had that a telescope with an f/5 focal ratio like the StarBlast 6 could hold its own at high magnifications. At 75x through the 10mm Plössl, these close pairs were elongated but not cleanly resolved. Once again, adding the 2x Barlow did the trick. On a whim, I decided to “go the max” and insert a 5mm eyepiece in the Barlow. I don’t recommend this practice — Barlows are better with low- to mediumpower eyepieces. At 300x, the theoretical upper magnification limit for a 6-inch scope, both pairs of the Double Double were spectacularly split. Taking a fun-to-use scope like the StarBlast 6 for a test drive quickly evolved into a cosmic joy ride. Still, I found that I could roll up my sleeves and put it to work making brightness estimates of variable stars. Its wide field (when used
Two eyepieces come with Orion's StarBlast 6 telescope. A 25mm Sirius Plössl provides a magnification of 30x. A 10mm Sirius Plössl yields 75x. The eyepiece rack mounts to the base and holds three 11⁄4" eyepieces.
with the 25mm Plössl) allowed me to capture the variable star and a useful quantity of nearby comparison stars. Using this eyepiece on an evening of less than ideal transparency, I was able to see stars as faint as magnitude 12.5. Switching to the 10mm eyepiece increased contrast, bringing in stars as faint as magnitude 13.
A scope for you? I confirmed my impressions of the StarBlast 6 at a star party held at the Amateur Telescope Makers of Boston clubhouse. About a dozen club members put the telescope through its paces. Their general consensus confirmed my own findings. Relatively inexpensive and easy to operate, the StarBlast 6 would make a worthy telescope for the beginner. If you’re an experienced amateur astronomer, you’ll appreciate this scope as a backup or travel instrument as long as you augment the 25mm and 10mm eyepieces with a 2x Barlow lens or a highpower eyepiece. For the past 5 years, kids have been having fun with the original StarBlast. With the StarBlast 6, we grown-ups can have our turn.
Contact information Orion Telescopes and Binoculars 89 Hangar Way Watsonville, CA 95076 [t] 800.447.1001 [w] www.telescope.com
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