ED Glass Element: The Alstar 2 inch Barlow lens utilizes ED glass to minimize visible chromatic aberrations; thereby significantly enhancing image clarity; Additionally, all lens surfaces are coated with a green multi-layer coating to effectively reduce reflections and improve overall optical performance
Large Lens Diameter: The 2 inch diameter also allows you to insert your 2 inch eyepieces into the Barlow lens doubling their magnification; The large lens diameter also means you will notice no shadowing in the image
Doubles the Focal Length: The Barlow lens can also be utilized for astrophotography; In particular when observing compact celestial objects a longer focal length may be necessary to ensure they appear at an appropriate size in the image; A significant advantage is that no shadowing occurs on camera sensors with smaller image formats
Precision Tool: Illuminated Reticle Eyepiece with red LED illuminated dual-line crosshair reticle precision tool for measuring double star separations planetary lunar dimensions and celestial position angles
Double Crosshair Eyepiece: The double crosshair design facilitates precise alignment of target objects enhancing the accuracy of locating and centering celestial bodies; This eyepiece is particularly suitable for guiding astrophotography when used with off-axis guiders or guide scopes