Improves the Clarity of Bright Objects in Refractors
With refractors, it's normal to see some purple fringing or halos around bright objects such as the planets, Moon, and bright stars. Such false color, or chromatic aberration, results from the inability of a standard two-element ("achromatic") lens assembly to focus all wavelengths of light to a single point. The effect is particularly pronounced at higher powers.The V-Block works amazingly well with achromatic refractors of any aperture or focal length. Its sophisticated coatings selectively block wavelengths in the violet and blue (<450nm) end of the visible spectrum, while allowing up to 95% transmission of the other wavelengths.Filter is in excellent condition. Paypal preferred(+3.5%)Thanks for looking.