SkyWatcher EvoStar 80ED Review
The Good
- •Great Optics
- •Ideal Size And Price For Beginner Astrophotographers
- •F/7.5 Speed Doesn’t Urgently Require A Field Flattener For Smaller Sensors
- •Useful For Visual Observing And Accessories Are Provided To Enable Such
The Bad
- •F/7.5 Speed And 600mm Focal Length Poor For Large Targets & Require Better Tracking/Guiding
- •Cannot Balance Without Purchase Of A Longer Dovetail Rail In Some Cases
- •Field Limited To Either Full Frame At F/7.5 Or APS-C + Reducer
- •ED Doublet Design Produces Slightly Inferior Images To A Triplet Or Petzval System
Review
The Sky-Watcher EvoStar 80ED is a budget-friendly option for beginner astrophotographers, offering sharp images with its FPL-53 ED doublet optics. While it may not be as high quality as more expensive triplet refractors like the Esprit, it is still capable of imaging larger deep-sky objects and can be mounted on medium-duty EQ5 class mounts such as the Sky-Watcher HEQ5 Pro for this task. Overall, the EvoStar 80ED offers good value for its price, and it also includes a full complement of accessories for you to use it for visual observation atop a suitable mount.
Optics
10
80mm (3.2”) Aperture
600mm Focal Length
f/7.5
Doublet FPL-53 optics
The Sky-Watcher Evostar 80ED is an ED doublet refractor using an FPL-53 lens element for one of the two piece of glass making up its objective, and high-quality Schott glass for the other, with an aperture of 80mm (3.2”) and a 600mm focal length for a resulting f/7.5 system. The Evostar 80ED uses the same optics as telescopes like the classic Orion ED80 and various other imported 80mm f/7.5 ED doublets, such as those formerly sold by Stellarvue.
At f/7.5 and 600mm focal length, the Evostar 80ED has a rather narrow field of view compared to faster instruments, and is less suitable for imaging the widest deep-sky objects. An f/7.5 refractor hardly needs a field flattener if you are just getting started and using a smaller sensor such as the APS-C found in many DSLR cameras. Larger sensors will need a flattener right away and are almost fully illuminated by the 80ED with minimal vignetting near the edges of the frame.
You can get a wider field of view and faster f-stop using the 0.85x reducer-flattener sold by Sky-Watcher if you are using an APS-C or similarly sized camera sensor. A reducer will cause vignetting with larger full-frame sensors, however, so you’re basically limited to the same field of view anyways – a reduced APS-C offers shorter exposure times and is probably cheaper, while a full frame sensor at f/7.5 offers a similar actual field of view but better sampling which can be particularly good for smaller targets. You can certainly shoot galaxies with 600mm of focal length provided you use a camera with smaller pixels and are okay with long exposure times at f/7.5; a larger fast Newtonian reflector or Cassegrain is more appropriate for the job, but requires a bigger mount.
Mechanics
8
The EvoStar 80ED has a 2” dual-speed Crayford focuser similar to the unit found on many Dobsonian telescopes. It is not ideal for imaging, lacking the stiffness of a 2” or 2.5” rack-and-pinion focuser, but works well enough with lighter cameras. Sky-Watcher’s 0.85x reducer-flattener can thread directly onto the back, or you can insert a flattener, adapter, or diagonal into the visual back (which does not use compression rings but simply digs into your accessory with thumb screws). A Synta/Vixen-style finder shoe is built into the focuser to attach the provided 9×50 finder or a guide scope.
To attach to a mount, the EvoStar 80ED comes with a pair of tube rings and a Vixen-style dovetail bar affixed to the bottom. With a heavy guide scope and camera/flattener attached to the back, the EvoStar 80ED may not be able to balance on a mount even with both the tube slid all the way forward in its rings and the dovetail all the way forward in the mount’s saddle. Installing longer aftermarket dovetail bars on the tube rings will give you more flexibility and allow you to attach a guide scope directly to the top of the telescope parallel with your equatorial mount’s declination axis for a rigid connection and minimal off-axis loads on the mount.
Accessories
The EvoStar 80ED includes a hard aluminum case, which isn’t anything fancy but does the job of protecting the telescope for storage and transport. You also get a 9×50 right-angle correct-image finder scope for aiming, a 2” mirror star diagonal with a 1.25” adapter, and two 1.25” LET eyepieces, each with a 55-degree apparent field of view: a 25mm for 24x and a 5mm yielding 120x. These are nice eyepieces, though you’ll want more eyepieces for additional magnification ranges and a 2” wide-angle eyepiece or two for more expansive low-power viewing with the EvoStar 80ED should you find yourself frequently using it for visual observation.
Mounting Options
The ZenithStar 81 weighs 7.8 lbs by itself; equipping it with a full complement of guiding accessories and a suitable camera/flattener can add up to close to 15 lbs, or around the limit of mounts like the Sky-Watcher HEQ5 Pro or Celestron Advanced VX and far too much for smaller equatorial mounts like the EQM-35 or star trackers. Autoguiding is, of course, a must at a focal length of over 500mm.
What can you see if you look through it?
When it comes to visual observation, the EvoStar 80ED can provide stunning views of the planets at high magnifications, and the provided 5mm eyepiece is ideal for the job. It’s easier to focus at f/7.5 and there’s slightly less chromatic aberration than in faster doublets, making the EvoStar 80ED much better for planetary viewing than faster and more imaging-oriented refractors. You’ll be able to see the phases of Venus along with tiny Mercury, as well as thousands and thousands of detailed features on the Moon, such as ridges, smoothed-out lunar maria, craters, and mountains. Mars’ ice caps and a few dark markings will also be visible when the planet is at its closest to Earth.
Jupiter’s moons, visible themselves even in the EvoStar 80ED’s 9×50 finder, can be seen as tiny disks when they transit in front of the planet and cast their shadows, while the 80ED has no trouble showing you Jupiter’s colorful cloud bands and storms including the Great Red Spot. You can also resolve the Cassini Division in Saturn’s rings alongside Saturn’s cloud belts and a handful of dim moons, including Titan. Uranus and Neptune appear as fuzzy bluish dots, with the latter nearly impossible to differentiate from a star as its disk falls just larger in angular size than the resolving limit of an 80mm Telescope.
While not able to provide as wide of a field of view as an instrument of shorter focal length, and of course limited by its small aperture, the EvoStar 80ED works well for deep-sky observation too, especially under dark skies with limited light pollution. You can achieve wonderful wide-field views of open star clusters and large nebulae, especially if you use 2” wide-angle eyepieces and/or possess a nebula filter. Galaxies, globular clusters, and planetary nebulae require a larger aperture telescope to see well, however. You can also split many double stars with the EvoStar 80ED even under very light-polluted conditions.
Value
9
Drawbacks
The EvoStar 80ED is not ideal for achieving a wide field of view with a full-frame sensor due to its limited image circle and long focal ratio. Its focuser is also not the best for carrying heavy loads and lacks the finesse of a compression ring for gripping diagonals and other accessories that have to be inserted rather than screwing on. Faster ED doublets or Petzvals may be ideal if a wide field is what you’re after, and if you want a long focal length instrument for imaging galaxies and other small targets there may be other picks. For visual use, an 80mm refractor is simply lacking in capability for such a high price tag despite the EvoStar’s superb optics and quality included accessories.
Conclusion
The Sky-Watcher EvoStar 80ED isn’t perfect, but it’s a decent beginner astrophotography telescope and a high-quality instrument for visual observation of brighter deep-sky objects alongside the Moon, planets, and double stars.