GSO's 2 2x ED Barlow is perhaps the best barlow of its kind on the market today, and one of our perennial best-sellers. This barlow uses two-element, fully-multicoated lenses made from special ED (Extra-Low Dispersion) glass for excellent color correction and sharpness. The lens ...GSO's 2 2x ED Barlow is perhaps the best barlow of its kind on the market today, and one of our perennial best-sellers.
This barlow uses two-element, fully-multicoated lenses made from special ED (Extra-Low Dispersion) glass for excellent color correction and sharpness. The lens edges are blackened to maximize image contrast. The clear aperture is 37mm so you can use even 2 wide-angle eyepieces without vignetting.
- The body is precision CNC-machined from aluminum and sports a handsome finish that you would usually find on much higher priced items. The barlow comes with a 2-1.25 adapter so it can be used with 1.25 or 2 eyepieces. The barlow tube and the 1.25 adapter both feature brass compression rings so the set-screw will not scratch your eyepiece barrels.
- A really nice feature of this GSO barlow is that the barlow element is housed in a separate metal cell at the bottom that can be unscrewed from the upper tube (see photos). You can then screw the barlow cell directly into 2 eyepieces with a standard 2 filter thread to increase the magnification of that particular eyepiece while still maintaining a low profile. When screwed into an eyepiece, the barlow will yield approximately 1.5x of magnification.
So, for example, a 30mm eyepiece can be used with the barlow element screwed on as a 20mm eyepiece, or with the complete barlow as a 15mm eyepiece. That's like having three eyepieces in one! You can also use the tube by itself without the barlow element as a 27mm (1.1) extension tube for 2 eyepieces and accessories. - Note that the use of any optical element like barlows and focal reducers changes the focus point of your telescope, requiring additional in-focus or out-focus travel.
This GSO 2 2x ED barlow will require at least 19mm (0.75) or more of additional in-focus travel. The exact amount of focus travel required will depend on the optics and mechanics of your specific set-up (telescope, diagonal (if used), barlow, and eyepiece). Hence, be aware that you may not be able to reach focus with all eyepieces or in all configurations with a given barlow.
- Specifications: Barrel Size: 2 inch (50.8mm)Magnification Factor: 2x - Coatings: Fully multicoated, Blackened lens edgesWeight:13.7ozHeight (Total):116mm - End Caps: 2Other: Includes 2 to 1.25 conversion adapter with brass compression ring - Made in Taiwan