SkyWatcher Refractor Esprit 150 ED APO optical tube

SkyWatcher offers a wide range of apochromatic refractor optics, with triplet optics and ED treatment . This treatment ensures the correction of the image aberrations , since it avoids an undesired dispersion of light, achieving a much greater sharpness of the image in its entire field. The image field that is achieved, due to the field flattener , is completely flat.
The Esprit 150 ED optical tube has an aperture of 150mm , focal length of 1050mm and focal ratio of 7. This short focal ratio makes it especially suitable for use in astrophotography . It incorporates a 9x50mm finder, 28mm LET eyepiece and focuser Crayford dual speed model, Track, which ensures smooth shift focus and 0 therefore more accurate.

The lenses in contact with the exterior have an anti-reflective coating, which ensures maximum light transmission, by a factor close to 99.5%. This treatment is called high transmission metal treatment. The objective lens cell is set up to reject residual light that is not focused. The tube itself is designed with internal baffles to ensure maximum contrast , eliminating unwanted light.
Includes Crayford Dual Speed 1:11 focuser with 360º rotation and 1.25 "and 2" adapters, Di-Electric 2 "diagonal, 28mm LET eyepiece, M-48 doublet field flattener and aluminum case.
Characteristics:

• Type: apochromatic refractor
  
• Optical scheme: Triplet ED
  
• Diameter: 150mm
  
• Focal length: 1050mm
  
• Focal ratio: f / 7
  
• Maximum magnification: 300x
  
• Coating: anti-reflective metallic treatment
  
• Focuser: 3 "double speed swivel with 1:11 reduction and 50.8 / 31.8 adapters
  
• Weight: 14.5 kg (OTA)
  
• Eyepieces and Accessories: 28mm Eyepiece 50.8 (37.5X) Concealer / Flattener with M48 photos of connectors, 50.8mm diagonal, rings, 75mm slide and rigid case.
  
• Seeker 9 × 50 at 90 °