Optics
The Evostar 80ED is an 80mm (3.1”) f/7.5 ED doublet refractor with a focal ratio of f/7.5 and resulting 600mm focal length.
The Evostar scopes all use FPL-53 ED and Schott crown glass in the lens elements. This results in a scope with rather low chromatic aberration, only detectable on the brightest stars, certainly an improvement over less-expensive ED refractors that might use FPL-51 or FK-61 glass, and of course far better than comparably spec’d achromats.
The scope’s slow focal ratio of f/7.5 additionally helps with controlling chromatic aberration and makes it easy to achieve high magnification without ultra-short focal-length eyepieces. For astrophotographic use, the 600mm focal length of the Evostar 80 means you can actually go after some stuff besides wide-field objects, albeit not as well as with a dedicated longer focal length scope.
Mechanics
The Evostar ED focuser is a relatively unsophisticated, 2-inch, dual-speed Crayford design. It doesn’t have any kind of tension adjustment, locks, or even a compression ring to grip 2” accessories like the provided diagonal, and it may slip under very heavy loads, but for a typical DSLR or color camera, it’s of little concern, and the motions are buttery smooth, while the focuser also easily accepts a motor focuser like the ZWO EAF.
The Evostar ED scopes come with a pair of white felt-lined tube rings and a green Vixen-style dovetail plate (the black version shown in the ads was phased out recently). The rings can easily have a second dovetail plate added on top for attaching a guide scope. The ProED’s dovetail has a ¼ 20 threaded hole for use on a photo tripod, but it’s rather heavy and inconvenient to use on one. Instead, you should probably use the attached Vixen-style dovetail to attach the scope to a compatible mount.
Accessories
The Evostar refractors all come with a 50mm, 9×50 right-angle correct image finderscope, a 2” star diagonal, and 20mm and 5mm eyepieces.
The 9×50 RACI finderscope is the same low-cost unit sold with many telescopes. It is probably an overkill if anything due to its large aperture, but it works well, though you might want to swap it for a lighter and more convenient red dot or reflex sight.
The provided 2” diagonal is pretty good, and you shouldn’t need to upgrade from it unless you’re really picky. The 20mm (30x) and 5mm (120x) long eye relief eyepieces are decent; they’re basically Plossl derivatives with twist-up eyecups. Both have a roughly 55-degree apparent field of view. The Evostar refractors all also come with a nice aluminum hard carrying case with a foam interior lining.
Mount Recommendations
The Evostar 80ED will work fine unguided for imaging on most EQ5- and EQ6-class mounts, but autoguiding is a good idea if you want to do exposures of a minute or longer. Our top pick for a mount would be the Sky-Watcher HEQ5i Pro/Orion Sirius, though any heavy-duty stepper-driven mount with autoguiding capability is ideal. A lightweight alt-azimuth mount such as the Explore Scientific Twilight I or Sky-Watcher AZ-GTi is ideal for visual use with the Evostar 80. An EQ3- or EQ4-class equatorial mount will also work, but it introduces unnecessary complications when setting up and using the scope and will bring the total weight up quite a bit.
Should I buy a Used Sky-Watcher Evostar 80ED?
There’s little that can go wrong with such an elegantly simple telescope as the Evostar 80ED that won’t be immediately obvious when purchasing a used unit, such as damage to the objective lens or focuser. However, be sure that you are getting the ED version and not an “Evostar” achromat, as some confusion exists between models due to Sky-Watcher’s ever-changing brand/name monikers.
Aftermarket Accessory Recommendations
For deep-sky astrophotography with the Evostar 80ED (as with most refractors), we highly recommend obtaining a field flattener. There are numerous third-party ones available, but Sky-Watcher also sells a 0.85x reducer/corrector for each Evostar model. Without a flattener, stars at the edge will look comatic and it will look like you are zooming towards the center of the field at Warp Speed on the Starship Enterprise – thankfully, this is not an issue that shows up during visual use.
Additionally, for visual observation, more eyepieces would be a good idea; almost anything will work well at f/7.5, and the provided pair may be all you need for higher magnificaitons, but a 2” wide-angle ocular like the Apertura 38mm SWA (16x) will provide the maximum possible field of view with the Evostar 80ED—just under 4.5 degrees, or nine times the apparent diameter of the full Moon in the sky, and enough to fit the entire Veil Nebula or Andromeda Galaxy in the field of view with ease. A UHC nebula filter such as the Orion UltraBlock will help bring out objects like the Veil Nebula under dark skies and improve views of the brighter emission nebulae like Orion from light-polluted locales with the Evostar 80ED or any other telescope.
Astrophotography Capabilities
The Evostar 80ED is a superb astrograph for deep-sky imaging when paired with a suitable mount, camera, and guiding system. With 600mm of focal length, you can still shoot wide-field stuff with the Evostar 8ED0 (a 0.85x reducer will bring the focal length down to 510mm), but it’s also possible to get good photos of the larger and brighter globular star clusters and galaxies with some effort. The nearly pinpoint, crisp stars provided by the Evostar 80 will look excellent, but as with any astrophotography, telescope focusing and good seeing are critical to achieving this in your images.
While planetary imaging is possible with the Evostar 80ED and a suitable Barlow lens/camera, 80mm of aperture is not enough resolving power for very good results, and a larger telescope is preferable.
What can you see?
The Evostar 80ED performs similarly to a slightly larger reflector or catadioptric, such as a 100-114mm, on deep-sky objects. The 600mm focal length and 2” focuser of the Evostar 80ED allow you to get a very wide field of view, particularly when it is equipped with a good 2” wide-angle eyepiece. Open star clusters such as M35, the Pleiades (M45), or others like M11 and the Double Cluster are stunning through the Evostar 80ED, though globular star clusters are for the most part featureless smudges, requiring a larger instrument to resolve, as is the case with planetary nebulae. The bright emission nebulae dotting the sky such as Orion (M42) and the Lagoon (M8) look great with the Evostar 80ED under dark skies—particularly when it’s paired with a UHC filter—but are still visible from the suburbs, while larger and fainter nebulae like the Veil require both a filter and dark skies to be seen at all but are spectacular in detail. Galaxies are little more than detailless smudges with only 80mm of aperture, apart from a few groups of galaxies and possibly hints of dust lanes in M31, M82, and a handful of other targets under optimal conditions. Plenty of double stars can also be split with the Evostar 80ED on a steady night.
The Evostar 80ED is also great on the Moon and planets, albeit limited by its small aperture. The phases of Mercury and Venus are easily seen, and you can at least resolve Mars’ polar ice cap when conditions are favorable, along with possibly a few dark surface markings (albeit barely) when the planet is closest to Earth. The Moon looks fabulous, as is to be expected with any good telescope, while the four Galilean moons of Jupiter are clearly visible in the Evostar 80ED’s 9×50 finder scope. Jupiter’s vivid equatorial cloud bands and the Great Red Spot can be seen along with other atmospheric features, though a larger telescope is required to resolve the disks and shadows of the Galilean moons. Saturn’s rings and the Cassini Division are a delight, and you can also see some of Saturn’s dull cloud bands and a few of its moons. Uranus and Neptune are fuzzy bluish dots if you can distinguish them from stars at all, requiring greater resolving and light-collecting power than the Evostar 80ED possesses to clearly see their disks or any of their faint icy moons. Pluto, of course, is hopelessly out of reach with such a small instrument due to its dimness.
