The Fringe-Killer Filter - 1.25-Inch by Baader Planetarium:

Baader's Fringe-Killer Filter minimizes unwanted blue fringing, comparable to a Minus-Violet-Filter, while retaining a very pleasing color balance. This is only made possible by applying modern DWDM plasma-assisted coating technology, allowing almost a hundred coating layers to be accumulated onto a panoptically polished substrate without destroying the optical figure. This fine optical tool will help a small refractor achieve the magnification advertised on the box. Performance rivals that of the most expensive color correcting lens systems, costing 20 times more! 

The coatings required to accomplish this innovative filtration are exceedingly complex, requiring almost 50 layers per side, using the latest DWDM Plasma assisted coating process. The Fringe Killer has perhaps the most complex coating ever achieved on an amateur astronomical filter. The Fringe Killer is the perfect compliment to the Baader Contrast Booster. The Contrast Booster is an aggressive filter, designed to deliver the maximum sharpness and contrast possible from an achromat. The result is complete removal of the violet haze, with a somewhat dimmer and yellower image. The Contrast Booster also incorporates additional RGB filtration for further enhancing color contrasts.

Digital Imagers (CCD, DigiCam, and Webcam) will find the Fringe Killer to be the ultimate mate for their achromatic refractor. The high transmission and fringe reduction work great for both planetary and deep sky imaging. Baader has also chosen to include their renowned UV/IR Cut coatings as part of the Fringe Killer formula. These coatings maintain very high transmission, with well placed sharp cutoffs in the IR and UV.

Baader Planetarium Fringe-Killer Filter Features:

• Offering the brightest image of all color-correcting devices in the industry, makes the Fringe-Killer a must for even the smallest of refracting (lens type) telescopes.
• Removes blue fringing as well as RED fringing above 656nm.
• Forms a "plateau" of 50-percent transmission in the blue spectral region from 450nm to 480nm, which is much more complex to produce than even the narrowest of all Nebula Filters.
• Retains the highest light transmission of all known color correcting devices be it filters or lenses in all important deep sky wavelengths from 486/501 up to 656nm.
• Built-in Infrared Blocker, ranging from 656 to 1150nm, makes it the perfect tool for CCD work, as well as afocal projection photography with digital cameras for the Moon and planets.
• The most subtle of color variations remain visible in planetary surface detail, due to the excellent color balance.
• Combine with the Baader Red 610nm color filter to receive an ultra narrow (~70nm) wide H-alpha pass band filter at an amazing 95-percent peak transmission, and at the world's lowest price!
• Combine with the 1.25-inch SkyGlow Filter for breathtaking contrast on lunar and planetary surface detail.
• Panoptically polished to achieve perfect sharpness, even when mounted way in front of a binocular viewer, or during afocal projection (digital imaging).
• No deterioration of resolution with magnification at 300 times or more, something that would not happen with the usual "flame polished" (raw polished) glass, commonly used for a wide variety of filters.
• Plasma-assisted, hardest, scratch proof and water impermeable dielectric coatings of almost 50 coating layers on either side, most carefully designed to extend equal tension onto either side of the substrate in order to retain the highest quality optical figure.

OPT Product Number: BA-FFK-1