Product Description
• dual-speed 2" Crayford focuser with 10:1 ratio fine focusing
• 2" dielectric star diagonal with 2" and 1.25" eyepiece holders
• two 1.25" Long Eye Relief eyepieces (20mm and 5mm)
• 8 x 50mm right-angle finderscope
• dovetail shoe for installing on a Celestron AVX go-to mount or any Vixen-style altazimuth or German equatorial mount
• two-year warranty
The Sky-Watcher Evostar 120ED uses a crown glass element, an ED glass element, and state-of-the-art optical multicoatings in its apochromatic ED doublet optics. The result is images that are essentially free of the annoying halo of unfocused violet light (chromatic aberration) that often mars the view of bright stars and solar system objects. In addition, there is no loss in contrast such as you will find in reflector and catadioptric scopes that have a secondary or diagonal mirror hanging in the light path to scatter light..
The 120mm Sky-Watcher doublet optics are even more appealing when you consider that this Sky-Watcher apo is loaded with features other manufacturers charge extra for (or don't even have available) - such as an 8 x 50mm right-angle finderscope, a 2" dielectric star diagonal with 1.25" and 2" compression ring accessory holders, two 1.25" LE (Long Eye Relief) eyepieces (LE20mm and LE5mm); and a foam-lined aluminum-clad carrying case.
The Sky-Watcher Evostar 120ED has enough premium high contrast/high resolution optical performance to let you use it as the heart of your observing system. With a weight of 11.3 pounds, it will work well on most medium duty equatorial mounts, but may start to push the capacity of some altazimuth mounts. That said, the Sky-Watcher Evostar 120ED is still light enough to take out and set up for observing on very short notice. Considering its surprisingly low price for an apochromatic doublet, adding in the extra features you get at no extra cost, and in view of the great optical performance that comes as standard equipment, the 120mm Sky-Watcher Evostar 120ED is a terrific buy!
Features of this telescope . . .
Apochromatic ED doublet refractor optics: 120mm (4.72") aperture, 900mm focal length, f/7.5 focal ratio. The ED element is precision-polished from high grade ED (Extra-low Dispersion) glass. This ED element produces superior sharpness and color correction by minimizing the chromatic aberration, the "false" color fringing seen around bright objects when light rays pass through standard crown-and-flint doublet objectives. The result is to reduce spurious color halos and fringing to vanishingly low levels.
Fully multicoated optics: Each air-to-glass surface in the Sky-Watcher PRO 120ED doublet objective lens has MHC (Metallic High-Transmission Coating) antireflection multicoatings on all air-to-glass surfaces for high light transmission, minimal light scatter, and excellent contrast.
Internal light baffles: Contrast-enhancing internal light baffles in the tube and focuser drawtube and a specially darkened tube interior provide dark sky backgrounds and high terrestrial contrast.
Dew shield: The supplied dew shield slows the formation of dew on the lens in cold weather to extend your undisturbed observing time. It also improves the contrast, similar to the effect of the lens shade on a camera lens, when observing during the day or when there is excessive ambient light at night, such as a neighbor's backyard security light. The substantial 11. 3 pound optical tube measures 37.8" long, including the dew shield. A slip-on metal dust cap is standard.
Dual speed 2" Crayford focuser: The precision-made no-backlash focuser has dual-speed focusing. There are two coarse focusing knobs. The right knob also has a smaller concentric knob with 10:1 reduction gear microfine focusing. This provides exceptionally precise image control during high magnification visual observing and critical DSLR or CCD imaging. The large focus knobs have ribbed gripping surfaces so they are easy to operate, even while wearing gloves or mittens in cold weather. Lock knobs lets you adjust the tension on the drawtube to accommodate varying eyepiece/photo accessory loads, as well as firmly lock in a photographic focus.
2" dielectric star diagonal: The supplied standard equipment 2" mirror star diagonal of the PRO 120ED slips into the focuser drawtube's 2" eyepiece/accessory holder. The 2" diagonal has 99% reflectivity dielectric mirror coatings for high light transmission. A supplied 1.25" accessory adapter slips into the 2" diagonal to let you also use 1.25" eyepieces. The 1.25" accessory adapter can also be inserted directly into the 2" accessory holder on the focuser drawtube to let you use a 1.25" image erecting diagonal, or 1.25" photographic accessories.
Supplied eyepieces: Two 1.25" long eye relief eyepieces are supplied as standard equipment - a 20mm (45x) and a 5mm (180x).
Finderscope: The Sky-Watcher Evostar 120ED comes with an 8 x 50mm right-angle finderscope that is fully-multicoated to insure maximum brightness and contrast.
Mounting dovetail: The Sky-Watcher Evostar 120ED apo has dual hinged split-ring tube rings and a dovetail mounting bar that fits directly into the Vixen-style dovetail slot on the head of many of the most popular medium capacity altazimuth and German equatorial mounts. Such mounts include the Astro-Tech Voyager altazimuth II and the Celestron AVX Advanced Series go-to equatorial, among others.
Shipping/storage case: The scope comes in foam-fitted aluminum-clad shipping/storage case.
Two-year warranty: The Sky-Watcher Evostar 120ED doublet apo is protected by a two-year limited warranty against flaws in materials and workmanship.
Tech Details
Aperture | 4.72" |
---|---|
Focal Length | 900mm |
Focal Ratio | f/7.5 |
Highest Useful Magnification | 257x |
Weight | 11.3 lbs. |
Optical Coatings | Metallic High-Transmission Coatings (MHC) |
Resolution | 0.97 arc seconds |
Supplied Eyepiece | two 1.25” LE (Long Eye relief) eyepieces (LET20mm and LET5mm) |
Telescope Type | Refractor |
View Finder | 8x50 |
Visual Limiting Magnitude | 12.9 |
Warranty | 2 years |
Reviews
The four stars is because as I just hinted, everything is is good (enough) quality. The cell is not colimatable. But mine was absolutely fine. The dew shield does not retract. The focuser is okay, it does not rotate which can be a pain on a GEM. The finder is super basic but works. The case is BARELY serviceable. Mine has edges coming apart. The rings are basic rings. The diagonal was okay but my star tests were done with a StellarVue diagonal. The two eyepiece are both surprisingly good. Not great. But better than you often get with a scope.
Seems SW spent the money where it should be on an APO OTA, on the optics!
I just do visual. Highly recommended. (Posted on 8/23/2019)
From my urban Sarasota backyard I aimed at M16 as a joke and with my unmodded DSLR knocked out 30, 30sec subs and stacked them DSS .... unbelievable..... this scope on its first night out tracked so well the image was for me mindblowing. The scope is long all right at 42inches but only weighs 13 lbs. You may see my image on CloudyNights under my username gbgrimm. (Posted on 10/25/2018)
Supplied Accessories
- 120mm f/7.5 ED doublet apochromatic optics
- Split hinged tube rings with a Vixen-style dovetail
- 8 x 50mm right-angle finderscope
- 2" dual speed Crayford focuser
- 2" dielectric star diagonal with 2" and 1.25" eyepiece holders
- 20mm (45x) and a 5mm (180x) long eye relief 1.25" eyepieces
- Dew shield
- Dust covers
- Foam-fitted carrying case.