TeleVue achromatic 2x Barlow lens 2" / 50.8 mm Big Barlow

TeleVue achromatic 2x Barlow lens 2" / 50.8 mm Big Barlow.

Properly designed Barlows do wonderful things: They amplify power, slow the telescope's f/# (improving eyepiece sharpness), and give designers the opportunity to compensate for eyepiece aberrations.

TeleVue Barlows use multi-coated high index glasses for optimum aberration correction, exceptional contrast with virtually no light loss. Observed performance is aberration free, even when tested with f/4 scopes. They even improve our competitor's eyepieces and telescopes!

Tele Vue Quality

Compromise image quality in any part of the optical chain and you've compromised every part! Tele Vue product design and execution deliver consummate satisfaction. Every Tele Vue Barlow must pass the same rigorous f/4, full field testing as all our eyepieces. All Tele Vue Barlows now use brass clamp rings for secure, non marring holding of eyepieces and accessories.

2" Barlows

Offered in 2x, this 2" Barlow includes parfocalization, 2" filter threads, captive lock screws that won't fall out and full multicoatings.

For astro-imagers, the below chart indicates the magnification for each Barlow (2x, 2x Big & 3x) as a function of distance from the Barlow top surface to the imaging surface (CCD or film).