The Celestron SkyMaster 15×70 occupies a useful middle ground among astronomy binoculars. Its 70mm objective lenses gather substantially more light than typical 10×50 binoculars, while 15× magnification provides enough image scale to reveal objects that can be difficult to distinguish at lower powers.
That combination makes the 15×70 particularly suited to exploring open star clusters, brighter nebulae and rich Milky Way star fields, while the Moon becomes a much more detailed target than it is through ordinary handheld binoculars.
There is a trade-off, however. At around 3 lb (1.36 kg), and with 15× magnification amplifying normal hand movement, the SkyMaster 15×70 sits near the point where mounting becomes highly desirable. It can be used handheld for short periods, but a tripod allows the binocular to show considerably more of what its 70mm aperture and higher magnification can deliver.
15× Magnification and 70mm Aperture
The combination of 15× magnification and 70mm objective lenses gives the SkyMaster considerably more reach than conventional low-power binoculars. In terms of objective-lens area, 70mm objectives provide nearly twice the light-collecting area of equivalent 50mm objectives, while the extra magnification makes smaller and fainter objects easier to distinguish against the surrounding sky.
Open clusters such as the Pleiades and Beehive Cluster are well suited to this combination of aperture and magnification, as are brighter deep-sky objects such as the Orion Nebula and Andromeda Galaxy. Under sufficiently dark skies, many other clusters and brighter nebulae also come within reach.
The Moon shows considerably more detail at 15× than through typical low-power binoculars, and Jupiter’s four bright Galilean moons can be visible as tiny points of light alongside the planet when conditions are favorable. The binocular should not, however, be regarded as a substitute for a telescope when higher magnification or detailed planetary views are the priority.
A Tripod Makes a Big Difference
At around 3 lb (1.36 kg), the SkyMaster 15×70 can be used handheld for short periods, but weight isn’t the only issue. At 15× magnification, small movements of the hands are magnified as well, making stars appear to shake and reducing the amount of detail that can be seen.
Supporting your arms can help for quick observations, but for longer sessions a tripod provides a noticeably steadier and more comfortable view. Celestron includes a tripod adapter with the binocular, allowing it to be attached to a conventional photographic tripod.
The 15×70 remains considerably easier to transport and set up than much larger 100mm binoculars, while offering enough aperture and magnification to make mounting worthwhile for longer astronomical observing sessions.
4.4° Field of View
Despite its higher magnification, the SkyMaster 15×70 retains a 4.4° field of view, allowing it to show a substantial area of sky at once. This preserves much of the sweeping, exploratory character that makes binocular astronomy appealing while providing noticeably more image scale than lower-powered models.
Large star fields and many open clusters fit comfortably within the view, and the relatively broad field also makes finding and moving between deep-sky objects easier than through a telescope operating at higher magnification.
The combination of a 4.4° field and 15× magnification therefore represents an interesting compromise: narrower than typical handheld binoculars, but broad enough to retain useful context around the object being observed.
Optics and Focusing
The SkyMaster 15×70 uses BaK-4 Porro prisms and multi-coated optics, while focusing is handled by a central focusing wheel with a separate right-eye diopter adjustment to compensate for differences between the observer’s eyes.
For astronomy, relatively little refocusing is required once the stars have been brought to a sharp focus. The binocular also provides 18mm of eye relief, giving eyeglass wearers some additional room behind the eyepieces, although whether the entire field is visible will depend on the observer’s glasses and eye position.
Limitations to Consider
The main limitation of the SkyMaster 15×70 is the compromise created by its size and magnification. At around 3 lb (1.36 kg), it remains reasonably portable, but 15× magnification makes prolonged handheld observing difficult. Using a tripod improves stability considerably but makes the setup less spontaneous than smaller, lower-powered binoculars.
Like other large straight-through binoculars, it can also become uncomfortable when observing objects high overhead on a conventional tripod, where the observer may need to adopt an awkward viewing position beneath the eyepieces.
The SkyMaster 15×70 is therefore most useful when its extra aperture and magnification matter more than maximum portability or grab-and-go convenience.
Who Is the SkyMaster 15×70 Best For?
The SkyMaster 15×70 is best suited to observers who want more reach than ordinary handheld binoculars without moving into the size and mounting demands of giant 100mm models. Its 70mm aperture and 15× magnification make it particularly useful for star clusters, brighter nebulae, the Moon and rich Milky Way fields, especially when mounted on a tripod. It is less suitable for observers wanting genuinely lightweight grab-and-go binoculars or those primarily interested in detailed planetary observing, where a telescope is the better tool.
Specifications
- Magnification: 15×
- Objective Diameter: 70mm
- Prism Type: Porro, BaK-4
- Field of View: 4.4°
- Exit Pupil: 4.7mm
- Eye Relief: 18mm
- Close Focus: 43 ft (13m)
- Weight: 48 oz (1.36 kg)
- Optical Coatings: Multi-coated
- Focusing System: Center focus with right-eye diopter
- Weather Protection: Water resistant
- Nitrogen Filled: No
- Tripod Adaptable: Yes; adapter included