About the Baader Contrast Booster Filter The Baader Contrast Booster Filter is much more than a simple minus-violet filter. Based on the popular Baader Moon & Skyglow filter, the Baader Contrast-Booster takes contrast enhancement and skyglow reduction to the maximum level possible from a filter. Not only does this filter deliver a significant enhancement to planetary and lunar contrasts, but it is designed to also totally eliminate the damaging blue de-focused haze present in achromatic refractors. Gone are the annoying blue halo and obscuring haze that surround and smear resolution and contrast. Subtle contrasts and colors are boosted, while displaying the full resolution your scope is capable of. Available in both 1.25" and 2" Round Mounted styles, the Baader Contrast Booster Filter combines a special proprietary melt of Neodymium glass with a carefully designed 23 layer dielectric long-pass blocker on one face, and a 7-layer ultra-low anti-reflection coating on the other face. By aggressively filtering out the defocused blue wavelengths, a light yellow tint is imparted to objects (noticeably less than a typical yellow filter). The special coatings enable over 95% transmission across key portions of the visible spectrum (including H-Alpha). This results in a filter that retains the colors and color contrasts in tough subjects like Jupiter, without excessive image dimming. Cloud bands retain their ruddy red hues, but now become more striking in contrast. The Great Red Spot finally becomes easier. Planets and Lunar landscapes are set against a jet black sky. The Contrast-Booster is a must for Solar observing when used in conjunction with Baader Astro Solar. As many users have found, the Baader Contrast Booster Filter is a great filter for Mars! The views of Mars with all telescopes (including reflectors and apochromats) benefit from the RGB filtration plus blue blocking. Combined with the Baader UV-IR-Cut Filter, the Contrast-Booster makes the ideal filter set for digital imaging. Rather than add the cost of additional IR filtration (only needed for digital imaging), the Baader Contrast Booster has been optimized for visual use. Digital imagers can simply add our Baader UV-IR-Cut Filter when needed. The true 1/4 wave fine optically polished surfaces guarantee the sharpness and contrast of the image. Filters are available in both 1.25" and 2" sizes. The base substrate of the Baader Contrast Booster Filter is a special custom melt of Neodymium-doped glass, designed for specific transmission characteristics, and made only for Baader Planetarium. In addition to it's unique spectral characteristics, the Contrast-Booster offers Baader's hallmark optical and mechanical features that set it apart and result in the best possible image sharpness, contrast, and real-world durability. Baader Contrast Booster Filter Features... Eliminates the color error present in economy refractors Removes the bluish "hue" (= lack of contrast) during lunar, planetary, solar, and terrestrial observation! Strongly emphasizes surface detail on Jupiter and Mars! If you have never seen the GRS (Great Red Spot) on Jupiter - you will with this filter! Over 95% transmission. Provides a bright, brilliant image compared to the usual dark green filters that are used to bring out detail on Jupiter. Color recognition will be retained! The ultimate in lunar filters! The Moon appears much more natural in color (with a slight yellowish tint), compared to the usual low-priced dark green Moon filters usually offered for beginner's telescopes. Completely removes distracting false color and the resulting smeared and washed out image details. You have never ever seen the Moon so tack sharp in an economy-priced telescope! Blocks atmospheric "stray light", also known as skyglow. Sky background turns into pitch black! Fits each and every standard filter thread. Combines with the Baader Infrared Cut-Filter. In this combination all blue scatter as well as unfocused near infrared light is completely removed - an absolute must for digital imaging! Planoptically polished, suitable for being used in front of a binocular viewer, or for afocal image projection during digital imaging (way in front of the focal plane!) No deterioration of resolution with magnifications of 150x and more unlike "raw polished" (flame polished) glass! Substrate (glass melt): Neodymium doped glass Rear Face Coating: 7-layer hard-multicoating, featuring 0.2% reflection Front Face Coating: 23-layer dielectric long pass blocker Ionbeam hardened coatings on both faces, absolutely scratch resistant...may be cleaned any time without Baader Contrast Booster Filter Specifications... Filter Type: Contrast Enhancement Format: Round, Mounted Aperture: Available in both 1.25" and 2" Coatings: Dielectric & Anti-Reflection Transmission: above 95% Substrate: Neodymium doped glass
