Optical Tube Performance of Nexstar 5SE
The Celestron NexStar 5SE is based around the C5 optical tube, a telescope with 45 years of heritage that has flown on Space Shuttle missions. The C5 is a Schmidt-Cassegrain. This means it does have a long focal length of 1250 mm, limiting its field of view somewhat especially given the scope’s 1.25”-only eyepieces. To some extent the scope is also “boxed in” to high magnifications.
A 2” diagonal can in fact be attached to the 5SE, but wide-field 2” eyepieces will vignette to the point that it’s not really worth the bother. The same is true of a dedicated f/6.3 reducer. Unlike other Celestron SCTs, the C5 also lacks Fastar/Hyperstar capability.
The 5SE’s 5” aperture is enough to show a fair amount of detail on the Moon and planets. However, its large secondary mirror, which obstructs 38% of the diameter, severely hampers resolution and contrast compared to a 5” Newtonian or Maksutov-Cassegrain, let alone a refractor. It also does reduce the light gathering ability (already fairly small) by a fair amount.
As with most decent telescopes, the Celestron NexStar 5SE optical tube comes with a Vixen-style dovetail, which allows for easy, tool-free attachment and balancing on its mount as well as numerous Celestron and third-party alt-azimuth and equatorial mounts which use Vixen saddles.
The 5SE does need to be collimated occasionally as it is a Schmidt-Cassegrain.
Having a Closer Look at the Accessories
The 5SE comes with a single 25mm 1.25” Plossl eyepiece which provides 50x magnification though you may want a 32mm Plossl and/or the aforementioned reducer-corrector for the widest field of view at low power. Additional medium and high magnification eyepieces of shorter focal length would be good to get the most out of your 5SE.
A quality 1.25” prism star diagonal is also provided for comfortable viewing, as well as Celestron’s StarPointer red dot sight which is used for star aligning the telescope during setup.
Reviewing the Mount Features
The NexStar SE mount is an upgraded version of the original NexStar 5’s mount, which was first released in the early 2000s.
It’s a simple alt-azimuth GoTo mount with a Vixen dovetail saddle that runs off fairly cheap servo motors. The NexStar mount is capable of pointing to something like 40,000 objects in its database, most of which are simply stars and consequently of little interest with the 5SE or indeed any telescope. A good chunk of the deep-sky objects in its database are also invisible with the 5SE, on account of their meager brightness or being in the wrong hemisphere of the sky to be seen from your location.
While this whole design works, the hand controller’s small buttons make it all too easy to push the wrong one, especially with gloves or simply large fingers. It also consumes batteries very quickly – you’ll need a 12-volt power supply for this scope. Lastly, entering the time and date is required on every boot of the mount, unless you obtain Celestron’s SkySync GPS accessory or their SkyPortal WiFi adapter, either of which costs over $75 as of the time of this writing. The SkyPortal WiFi adapter also mitigates the annoyance and limitations of a traditional hand controller by allowing you to control the scope with your phone, at the expense of drawing significantly more electrical power from your scope/battery as well as eating up your phone’s battery charge. The SE mount is pretty steady, but it can still be bumped. If this happens, one must re-boot and re-align the mount.
The 5SE comes with a built-in equatorial wedge, so in theory, one can polar align it and do long-exposure astrophotography. However, the wedge has no fine adjustments and cannot be adjusted in azimuth, so it is basically useless. Additionally, the mount’s low-precision gears and the 5SE’s long focal length make it ill-suited for long-exposure astrophotography anyways.
Should I buy a Used NexStar 5SE?
A used 5SE is a decent scope. Keep in mind that you will still have to buy additional eyepieces to get the most out of the 5SE unless the seller is nice enough to throw some in.
The 5SE isn’t awful, but we’d recommend other computerized telescopes – or a Dobsonian – in its stead if possible.
- The Celestron NexStar 6SE offers the aperture that the 5SE lacks while otherwise remaining identical and with a similar form factor.
- The Celestron Astro-Fi 130 has a similar aperture to the 5SE, but with a wider field of view, lighter weight and an easier-to-use computerized mount controlled by your phone or tablet.
- The Orion XT8i has more aperture and better accessories than the 5SE, and while it’s not a full GoTo it can be moved manually and aimed with the assistance of Orion’s computerized IntelliScope system.
Aftermarket Accessory Recommendations
The 5SE’s lone 25mm Plossl eyepiece really doesn’t allow you to get the most out of the telescope when it comes to high-resolution views of the Moon and planets. As such we’d recommend a high magnification eyepiece such as the 6mm “goldline” (208x) . For medium power, you might want a 15mm goldline or 15mm Agena Starguider for 83x.
The 5SE could really use a dew shield. A dew shield is just a flat black plastic or rubber cylinder that goes on the front of the telescope, blocking out stray light and preventing dew/frost from forming on the corrector lens which can fog up the view as well as eat away the coatings over time. You can make one yourself or buy one from AstroZap.
What can you see?
The 5SE’s small aperture and narrow field of view make it primarily a lunar, planetary, and double star instrument. It’ll show you lunar craters and mountains just a few miles wide, the phases of Venus and Mercury, the cloud belts of Jupiter and Saturn, Jupiter’s Great Red Spot and the Cassini Division in Saturn’s rings, the two gas giants’ various moons, and you’ll be able to see Uranus and Neptune as bluish, star-like dots. The 5SE will also have no trouble splitting double stars as close to an arc second apart under clear and steady skies.
As for deep-sky objects, the 5SE’s small aperture is the biggest limiting factor even under dark skies. You’ll be able to spot most of the objects in the Messier catalog and view globular clusters and galaxies, but resolving individual stars in globular clusters – as well as detail in most galaxies such as spiral arms or dust lanes – will be challenging, even if you are in dark skies far from light pollution. From the suburbs, the 5SE is likely to disappoint on all but the brightest nebulae and star clusters such as M42, M27, and M13.
What’s The Bottom Line?
At the end of the day, the biggest problem with the Celestron 5SE is simply price and lack of capability for the money. Yes, it’s portable and looks good, but for not much more money you could get the Nexstar 6SE, or you could get the (admittedly less than perfect, but extremely capable for the price) Astro-Fi 130. Either will show you more and provide much better value.