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Astronomik Blue Type 2c Filter - 31 mm Round - B-31

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SKU: ASF-B-31

Astronomik 31 mm Round Blue Filter

  • Astronomik 31 mm Round Type 2c Filter in Blue with a transmission of almost 100%
  • The effects of scratching, aging, and high humidity are negated by this filter's coatings
  • This filter is diffraction limited and therefore will not lower the optical performance level of your telescope system
  • Astronomik has modified the transmission of this filter in order to enable optimal color reproduction for simple image processing
  • Extremely short exposure times are enabled by higher transmission
  • Since this 31 mm Blue Filter blocks the IR, no additional filter is required
  • Made in Germany, a country known for producing optics of superior quality!


More About Astronomik 31 mm LRGB Filters

With transmission properties ideal for CCD astrophotography, Astronomik 31 mm round LRGB filters enable pure color reproductions of all sorts of objects, including planets and stars as well as emission and reflection nebulae. While filters from other brands have to make unusual compromises, these Astronomik filters offer the finest color reproduction possible. Stars as well as objects that only emit in spectral lines will be seen in their true colors. In fact your images will have such flawless colors, it'll be as if the featured objects were bright enough to see in the daytime. This represents the fundamental difference between Astronomik filters and filters from other manufacturers.

The act of taking the image is not the end of the process for Astronomik. They realize that astrophotographers want a tool that offers a simple, efficient editing procedure. To retain the color, Astronomik has calculated their filter set for the sRGB color space, used as an industry standard for companies that produce monitors, printers, and imaging software. Astronomik L-RGB filters separate the spectrum into four components: red, green, blue, and luminance. Hence color separation can be attained with pure black & white CCD sensors. The separation corresponds to the human eye's color sensitivity per DIN 5032. Use of the sRGB color space allows image color to be maintained throughout the complete image processing and output. The Astronomik L-RGB filter set enables the production of ideal raw material for image processing in the sRGB color space.

Due to the high-precision machining of the carrier substrate, Astronomik filters are parfocal with wedge errors below all usual margins. Astronomik filters are diffraction limited to keep them from being the weak link in an otherwise high-quality optical system. Focal distance problems as well as the precise location of the images in each color image are no longer concerns! These filters also offer total resistance to scratching, high humdity, and the effects of aging. Each filter comes with its own high-quality, long-lasting plastic storage box.

Transmission Specifications

  • Above 99% transmission
  • Obstructs unwanted Infrared wavelengths