Baader IR Pass Filter 685nm

Baader IR Pass Filter 685nm


  • €89,95
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Baader IR Pass Filter 685nm

The secret of good planetary images, the Baader IR-Pass Filter 685nm can greatly improve image sharpness by reducing the effects of seeing.

Baader IR-Pass filter blocks wavelengths below 670 nm. At these longer wavelengths, planetary images are less disturbed by atmospheric conditions. By combining a luminance image taken with the IR-Pass filter, along with RGB frames, overall image sharpness is significantly enhanced. There are some amazing images taken of the planets using this technique.

Alongside superb planetary images from the Baader IR-Pass Filter 685nm, it is also possible to take exceptional lunar images even in the daytime and evening, excellent image results have been seen of the lunar surface whilst the sun is still 35 degrees above the horizon! The IR-Pass filter provides a dark background and good contrast of the lunar surface under these conditions.


Freedom from Ghosts and Halos:  Baader Planetarium's filters have always been halo and ghost free.  Baader balances each dielectric coating stack to avoid the ghosts and annoying halos that plague other mfgr's filters.

Stackability:  Unlike most other filters, Baader Planetarium  filters are truly designed to be stacked and combined.  This is possible due to the high optical quality and highly efficient anti-reflection multicoatings.  The ability to combine filters opens up many interesting possibilities, permitting  unique spectral characteristics unachievable with any single filter.

Special Filter Cell:  Baader's special filter cell design offers unique features that enhance their reliability and usability.  Though difficult to produce, the ultra-thin filter cell results in the maximum possible clear aperture, in order to minimize vignetting (1¼" Filter clear aperture is 27mm!, 2" Filter aperture is 45mm).  The special threading has been designed to fit the wide variety of eyepieces and accessories (there is significant variation between the 1¼” filter threading used by eyepiece and accessory manufacturers).  The front 'crown' of the filter incorporates milled notches which make handling and threading the filter a more secure operation in the dark.



  • Baader IR-Pass Filter 685nm
  • Reduces the effect of seeing resulting in a much sharper image.
  • Tip for use: Ideal for imaging and used for the luminosity channel.
  • The effect of use: The normal spectral bandwidth is 400-700nm. This filter starts at 670nm in the deep red, just in the visual range so it can be focussed correctly. At this long-wavelength spectral range the atmospheric air turbulence (seeing) has much lower impact on the sharpness. Dark structures on Mars, Jupiter the Moon and the Sun are thereby rendered much sharper. The luminosity can then be combined with RGB creating a very sharp LRGB image.
  • Highly recommended for any planetary imager.
  • Reflex free anti-reflective and optically polished.

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