Alpine Astronomical Baader Contrast Booster Filter (1.25' Eyepiece Filter)

Alpine Astronomical Baader Contrast Booster Filter (1.25 Eyepiece Filter)

Much more than a simple minus-violet filter, and based on the popular Baader Moon & Skyglow filter, the Baader Contrast Booster Filter, from Alpine Astronomical takes contrast enhancement and skyglow reduction to the maximum level possible from a filter. Not only does this filter deliver a significant enhancement of planetary and lunar contrasts, but it is designed to also totally eliminate the damaging blue defocused 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.

The Contrast Booster 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 antireflection 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 Lunarscapes are set against a jet black sky. The Contrast-Booster is a must for Solar observing (with Baader Astro Solar). And, as many users have found, this 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.

• Eliminates the color error of economy refractors.
• Clearly puts the real quality of the lens on display.
• 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 - with this filter you will.
• Over 95 % transmission - provides a bright, brilliant image compared to the usual dark green colour filters, used to bring out detail on Jupiter. Color definition is retained.
• The ultimate in lunar filters. Moon (and Sun) appear much more natural in color (with a slight yellowish tint), compared to the usual low priced dark green Moon-filters, usually offered for beginners telescopes.
• Completely removes distracting false color and the resulting smeared and washed out image details. You have never ever seen the Moon or the Sun (with AstroSolar Safety Film) so tack sharp in an economy achromatic telescope.
• Blocks atmospheric stray light (skyglow). Sky background turns into pitch black.
• Fits into 1A¼ and 2 standard filter threads. Planeoptically polished, suitable for being used in front of a binocular viewer, or for a-focal image projection during digital imaging (way in front of the focal plane).
• No deterioration of resolution with magnifications of 200x and more - as with raw polished (flame polished) glass. Substrate (glass melt) Neodymium doped glass.
• Coating / rear face: 7-layer hard-multicoating, featuring 0.25% reflection.
• Coating / front face: 23-layer dielectric long pass blocker.
• Ionbeam hardened coatings on both faces, absolutely scratch resistant - may be cleaned any time without fear. Non-aging sealed coating edges.
• A significant part of city light pollution, as well as atmospheric Airglow is removed from the telescopic image.