Celestron Advanced VX 6″ SCT Review: Master of None
- •150MM APERTURE
- •MOUNT HAS A LOT OF FEATURES
- •POOR APERTURE VALUE FOR THE MONEY
- •NOT PARTICULARLY USEFUL FOR ASTROPHOTOGRAPHY
Advanced VX 6” SCT is overkill for a visual setup.
Celestron’s Advanced VX 6” Schmidt-Cassegrain bundles their highly praised C6 optical tube with the sturdy, albeit less-than-perfect, Advanced VX mount. It’s a decent choice for a general-use telescope, though if you’re planning on doing visual observing there are bigger options and for astrophotography there are easier rigs to start with.
150mm (6″) Aperture
1500mm Focal Length
f/10 Focal Ratio
The Advanced VX 6 optical tube is the Celestron C6, which is a 6” f/10 Schmidt-Cassegrain. The C6 is the newest of Celestron’s standard SCT models, having been released as recently as 2006 (the other Celestron SCT models were devised in 1970, 1977, and 1993 for the C5/C8/C14, C11, and C9.25 respectively).
VX 6″ SCT isn’t ideal for wide-field vistas of star clusters and nebulae.
Thanks to its small size, the C6 doesn’t really suffer from the mirror flop problems that plague larger Schmidt-Cassegrains nor a particularly narrow field of view. That being said, despite being physically compatible with a 2” diagonal, the C6 cannot actually illuminate the field of view of a 2” low-power eyepiece and will vignette quite badly with an f/6.3 reducer. Thus, the scope isn’t going to provide a field of view much larger than 1 degree (about 2 full Moons) – which means it isn’t ideal for wide-field vistas of star clusters and nebulae, though a 1-degree field is still plenty big to satisfy most users.
What can you see inside The Solar System?
Mercury ⧃ Phases.
Venus ⧃ Phases.
The Moon ⧃ A ridiculous amount of detail, with features as small as a mile visible. We could go and write paragraphs about how great the views of the Moon are with the 6SE - or arguably any decent telescope - but we couldn’t possibly do it justice, so we’ll let the views speak for themselves.
Mars ⧃ The ice caps are fairly obvious even when Mars is far from Earth. Around opposition you can see a bunch of dark shaded areas, which are just duller colored sand.
Jupiter ⧃ The cloud bands and Great Red Spot look great. With good seeing you can pick out mottled details and ripples within the cloud bands and the brownish polar zones. Jupiter’s 4 large moons are especially obvious as disks when they eclipse and transit the planet.
Saturn ⧃ Saturn’s rings are easily visible as is the Cassini Division in them, the latter provided you have good seeing. Around half a dozen moons can be spotted along with faint variations in the tones of Saturn’s cloud bands. Saturn’s largest moon, Titan, is visibly not a star and appears a slightly gold color.
Uranus ⧃ A small turquoise dot. The moons are out of reach of anything under 10 inches in aperture.
Neptune ⧃ A near-stellar blue dot. Its largest moon Triton can just barely be glimpsed under dark and steady skies.
What can you see outside The Solar System?
Outside the Solar System, the C6 is a solid performer, albeit limited somewhat by its aperture and field of view. You can expect to see a lot of open star clusters like M35, M11, and M67. Some large clusters like the Pleiades (M45) and Beehive (M44) cannot fit in the field of view with the C6, though they can still be enjoyed. The bright globular star clusters such as M13, M15, and M22 are kind of resolved with 6 inches of aperture – though barely, and only with fairly decent skies. Smaller globulars will remain fuzzy patches of light.
The few bright emission nebulae that dot our skies look magnificent in the C6, particularly if you use a good UHC nebula filter on them. The Trapezium star cluster’s fainter members nestled within the heart of the Orion Nebula are an easy catch. Planetary nebulae look decent with the C6, and some begin to show teal or blue coloration.
The C6’s aperture is enough to start showing you a fair amount of galaxies, but you won’t see detail unless you are under truly dark skies. With dark skies, however, galaxies start to come alive – M51’s spiral arms can be vaguely glimpsed as can the dust lanes in M82, M64, and M31. M33, M63, and M101 may also reveal faint spiral arms.
The C6 is also a fantastic double star splitting scope, especially thanks to its lack of diffraction spikes from spider vanes that a Newtonian reflector typically suffers from. Sub-arcsecond doubles are possible with good seeing conditions.
HyperStar by Starizona
Astrophotography With Hyperstar
The C6 also has HyperStar compatibility. This means that with Starizona’s Hyperstar corrector, you can remove the secondary mirror, stick the Hyperstar in its place at the front of the telescope, and image with an astro camera at a focal ratio of f/2.
However, the C6 only works with relatively small sensors in its Hyperstar configuration both due to the physical constraints of the design and the fact that a large camera housing can start to obstruct most of the telescope’s aperture. If you’re planning on doing deep-sky astrophotography with the Advanced VX 6, we would advise you to do it with the Hyperstar.
Being a Schmidt-Cassegrain, the C6 does need to be collimated from time to time. Contrary to what some folks might tell you, this is not a particularly scary or difficult process and absolutely does not require sending it back to Celestron. You simply adjust 3 small screws on the secondary mirror housing while pointed at a bright star – it’s arguably easier than collimating a Newtonian.
Collimation of VX 6″ SCT is easier than you might think.
Optical Tube Weight
The C6 optical tube also sports a Vixen dovetail bar to easily attach it to the Advanced VX or any Vixen-compatible mount. At only 10 pounds, it will fit many lightweight “grab n’ go” alt-azimuth mounts.
German Equatorial Mount
The Advanced VX is the smallest of Celestron’s computerized mounts. It’s robust and capable of holding scopes quite a bit bigger than the C6, and can be used for deep-sky astrophotography. Operating it is the same as any Celestron computerized scope/mount with the NexStar+ GoTo hand controller.
Vixen Dovetail Bar for the Optical Tube
VX 6″ SCT is not exactly fun to haul out for a casual observing session.
However, the Advanced VX suffers from a fair amount of backlash when autoguiding compared to many of its competitors, making it a less-than-ideal choice for serious deep-sky astrophotography. And for visual use with the C6, it’s quite overkill and takes a while to assemble and set up.
At 35 pounds without the counterweight, it’s not exactly fun to haul out for a casual observing session.
6×30 Finder – 25mm Plössl Eyepiece
25mm Plössl Eyepiece
The C6 comes with a single eyepiece – a 25mm E-Lux Plossl providing 60x. It’s a good starter eyepiece for low magnification, but as with any telescope you’ll want at least a few extra eyepieces providing a range of magnification options.
25mm E-Lux Plossl provides 60x magnification.
The finderscope included with the C6 is a simple 6×30 unit. While not our favorite, it serves adequately for the task of aligning the Advanced VX mount, and doesn’t have a battery to accidentally drain like a red dot finder does.
Poor Aperture Value
Not for Astrophotography Without HyperStar
The C6’s small field of view is a bit of a concern to us when it comes to viewing deep-sky objects. For astrophotography, the slow focal ratio of the C6 and the high cost of a HyperStar system or a focal reducer are also issues.
The main issue, however, is that the Advanced VX mount’s backlash and incompatibility with some software such as EQMod makes its tracking relatively mediocre even with autoguiding. Various modifications can improve the VX’s performance but at the end of the day the cheap servo motors in the mount and the poorly manufactured declination axis really limit its astrophotography capabilities.
The Advanced VX 6” SCT is a bit of a jack of all trades, master of none. It’s not the best at anything it’s capable of doing, but it’s a well-made piece of equipment that can accomplish a lot of different tasks, which can allow you to perhaps later figure out what you might want to purchase that’s more specialized.