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Televue 2 inch 4x Powermate with Eyepiece Adapter
Tele Vue Barlows An Optically Perfect Window Properly designed Barlows do wonderful things. First, they amplify power while retaining the eyepiece's eye-relief. Second, they slow the telescope's f/#, which improves eyepiece sharpness. Third, the designer can introduce compensations for eyepiece aberrations. The 4X Powermate Barlow is a parfocal, compact amplifying lens system. POWERMATE consists of a negative achromatic doublet plus a positive pupil-correcting doublet. While it looks and functions like a Barlow, your eyepiece will operate with pupil locations where the designer intended, avoiding mismatch problems. POEWRMATE

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Price: $350