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Baader Planetary Observation Colour Filters and Colour Filter Sets

SKU 2458301

Availability: Immediate Dispatch

  • Dark Blue Filter, Light Blue Filter, Green Filter, Yellow Filter, Orange Filter and Red Filter coloured filters
  • Available as six individual colour filters or in a complete filterset
  • Available in 1¼" and 2" threads
  • Used for contrast enhancement of lunar and planetary observations
  • Has the largest aperture/free opening of all the colour filters on the market which eliminates any vignetting.
  • Phantom Group Coating - Double 7-layer anti-reflection coating with only 0.25% residual reflection per surface resulting in no reflections, scatter or image dimming.
  • Planeoptically polished for sharpest image quality at high magnification.
  • Non-ageing sealed coating

These Baader colour filters are carefully prepared for amateur astronomical use for contrast enhancement of lunar and planetary observations. Colour filters are often identified with a Kodak Wratten (W) number. Baader colour filters were developed and manufactured to correspond to the respective wavelength range following the Wratten nomenclature:

  • Baader-red filter ≅ W25,
  • Baader-Orange filter ≅ W21,
  • Baader-yellow filter≅ W12,
  • Baader-green filter≅ W58,
  • Baader-light blue filter ≅ W80A,
  • Baader-dark blue filter≅ W38A

Below is the transmission curve of the Baader colour filters.

Baader Colour Filters Transmission

The filters are screwed into the filter thread of eyepiece barrels or in planetary imaging camera nosepieces (e.g. Skyris). A thread at either end of the filter allows the filters to be combined (i.e. stacked) with each other or with other filters (for example with the Baader UV / IR infrared cut filter).

The glass are co-planar fine optically polished. These filters exceed the quality of the usual "raw polished" (hot flamed) coloured glass filters. As they are fine optically polished, these filters can be at any point in the mean path - far ahead of the focal point (for example, in front of a binocular approach!) without causing defects (astigmastism) or to degrade the image otherwise in any way! The parallelism of the optical surfaces is excellent to within 30 arcseconds meaning that "double images" are not present. The transmission curve for each filter colour is also supplied. 

Filter Use
Filter Uses
Red 610nm longpass filter with steep absorption edge.  
  • Filters the H-alpha line from the visible spectrum.
  • Blue and Green lights is almost completely filtered blocked increasing contrast between the light and dark bands on Jupiter and Saturn.
  • Most interesting filter to use for observing the polar caps of Mars.
  • An optimum filter for daily observation of all the planets.
    Orange 570nm longpass filter.
    • Contrast enhancement for lunar and planetary observations at dusk.
    • Improves the detection of dark areas on Mars and penetrates the hazy atmosphere of Mars.
    • Shows more detail in the cloud bands of Jupiter and Saturn.
    • Suited for daytime observations of the Moon, Mercury and Venus.
    Yellow 435nm Longpass filter.
    • Suppresses the secondary blue spectrum when using achromatic and half-apochromatic refractors (increasing image sharpness).
    • For visual and photographic planetary observations.
    • Enhances contrast between the belts on Jupiter.
    • Increases contrast of the lunar and Martian surface.
    Green 500nm bandpass filter.
    • Provides the sharpest images with achromatic and refractors (eg double star observations.
    • Improves the visibility of CO2 Hoarfrost and ground fog on Mars.
    • Increases contrast between red and blue regions on Jupiter and Saturn.
    • Provides the best contrast for lunar craters Tyco, Copernicus and Kepler.
    Light Blue 470nm bandpass filter.
    • For visual and photographic planetary observations.
    • To observe high clouds on Mars, enhances contrast of hazes on terminator of Mars (Violet Clearing).
    • Displays reddish structures darker, ideal for observing the red spot on Jupiter. Also shows Saturn rings better.
    • To monitor the structures in the atmosphere of Venus.
    • Highlights the fine details in gas tails produced by comets.
    Dark Blue 435nm bandpass filter.
    • For visual and photographic planetary observations.
    • Aids in better detection of Venus phase.
    • The Violet Clearing on Mars can be seen better.
    • Enhances the Great Red Spot on Jupiter and contrast between the belts.
    • Enhances the contrast between zones on Saturn.

    • Largest free opening of all colour filters on the market to elimante any vignetting.
    • CNC machined "grip crown" provides excellent handling and comfort.
    • Both sides 7-layer AR coating with only 0.25% residual reflection per surface. This is the most antireflective that has ever been undertaken with color filters.
    • Planeoptically polished to within 30 seconds of arc for a sharp image at high magnification with non-ageing sealed coating edges.
    • Multi-coated for max contrast – no reflections, scatter or dimming.
    • The most important criterion for any kind of light filtering is brigthness. Certain spectral ranges at high magnification will only work at the highest light transmittance.
    • The long-pass filter in this filter set offers 98% transmission and produces no flare. Unmatched by other brands. This can be seen in comparison with standard colour filters at once - the filter colour radiant downright.
    • The combination of our infraread (IR) cut filter 1¼" and the RG 610 red filter results as an extremely narrow-band H-α pass filter for the CCD photography of red emission nebulae - at a ridcidulously low price!
    • A wide range of adaptors allow the uses of T-2 photo threads (See: Baader Astro T-2 System™).
    • Baader Phantom Group Coating™ developed by Baader Planetarium the coating is a 7-layer broadband coating with extremely low residual reflection. The term "Group" indicates that the respective most effective anti-reflection layer system was calculated for each type of glass of the filter. This means that the anti-reflection layers of different colour filters are different. They are calculated to provide the mximum for the respective filtered colour transmission values. Both sides of the filter are coated with 7-layer AR coating with only 0.25% residual reflection per surface. This is the most that has ever been provided for colour filters. The filter discs are screwed into the blackened aluminium frames and are delivered within a filter. Each filter is designed for multiple applications.
    MANUFACTURER Baader Planetarium
    TRANSMISSION RANGE multiple bands (see spectral image)
    AR-COATING Phantom Coating® Group, planeoptically polished
    FILTER SIZE 1 25 inch / 2 inch
    FILTER USAGE Color, Planetary
    FILTER MOUNTED Mounted (LPFC 6mm)
    TYPE OF FILTER Bandpass, Longpass
    SINGLE OR SET? Filter-Set
    FILTER SHAPE round