Sky-Watcher Evostar 120 ED OTAW Black Diamond (SW-2010)

This refractor telescope is a larger version of the popular EQ100 model, featuring a 120 mm lens while maintaining a focal length of 900 mm. Like its smaller counterpart, it is widely used by astrophotographers. The combination of high-quality optics, a precise focuser, and a lightweight design makes it an excellent choice for astrophotography. Additionally, the telescope can be upgraded with a 0.85x focal reducer, which also flattens the field of view. This modification results in a corrected system with a focal length of 765 mm and an aperture ratio of f/6.38.

Optical System
The telescope features a doublet refractor design made with low-dispersion ED glass (FPL-53). This optical system ensures excellent image brightness and minimizes chromatic aberration. It is ideal for observing planets, the Moon at high magnifications, and astrophotography. Apochromatic lenses focus nearly all visible wavelengths at a single point, correcting chromatic aberration in blue, green, and red light while eliminating spherical aberration in red and blue light. The telescope collects approximately 290 times more light than the human eye at night, allowing observation of objects up to magnitude 12.5 (compared to the naked eye limit of magnitude 6). Its optical resolution allows it to separate stars that are more than 1.2 arcseconds apart.

Focuser
The telescope is equipped with a high-precision focuser featuring a micrometer planetary gear transmission with a 10:1 reduction ratio. It supports both 2-inch and 1.25-inch eyepieces for versatile use.

Applications and Observation Capabilities

• Solar System: Observe lunar surface features larger than 1–1.5 km, sunspots and their structure, all planets in the Solar System, Mercury and Venus phases, Mars' polar caps, Jupiter's equatorial stripes and Galilean moons, Saturn's rings and Titan, Uranus and Neptune as disks, asteroid motion against stars, and brighter comets.

• Stars: View approximately 1.1 million stars up to magnitude 12.5, double and multiple stars separated angularly by more than 1.2 arcseconds, and observe star colors for brighter stars.

• Nebular Objects: Observe nearly all Messier catalog objects, hundreds of globular clusters, open clusters, brighter nebulae, and galaxies.

• Terrestrial Observation: With a prismatic angular attachment, the telescope can be used for terrestrial observations or as a high-quality telephoto lens for photography.

Included Accessories:

• LET eyepiece (28 mm; 2-inch)

• Straight-through finder scope (9x50)

• Dielectric diagonal (90°, compatible with 2-inch/1.25-inch eyepieces)

• Tube clamps and dovetail rail

• Aluminum transport case

Technical Data:

• Optical System: ED Doublet

• Lens Diameter: 120 mm

• Glass Type: Japanese FPL-53 (ED) with Schott-AG crown glass

• Focal Length: 900 mm

• Weight: 5.3 kg

• Focuser: 2-inch with micrometer planetary gear (10:1)

• Optical Tube Dimensions: 130 x 920 mm

This telescope offers excellent performance for both celestial observation and astrophotography while remaining versatile enough for terrestrial use when paired with the appropriate accessories. Its high-quality optics and lightweight design make it an ideal choice for both beginners and experienced users looking to explore the night sky or capture stunning images of celestial objects.