ANTLIA IR-Pass 685nm Planetary Imaging Filter - 1.25"


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ANTLIA IR-Pass 685nm Planetary Imaging Filter - Mounted in 1.25" Filter Cell (31.8mm)

The Antlia IR Pass 685nm filter is an absorption filter that allows infrared light with wavelengths of more than 685nm to pass through. It nicely complements the Antlia 850nm IR-Pass filter. At these longer wavelengths, the sensitivity of the unaided eye is reduced, so it is not suitable for visual observations. The filter is highly recommended for any planetary photography. At long-wavelength spectral range the atmospheric air turbulence (seeing) has much lower impact on the sharpness. The closer to the infrared band, planetary images are less disturbed by wavefront distortions in the atmosphere (seeing), and this results in the sharpest and highest contrast images possible.

By combining a luminance image taken with the IR-Pass filter, along with RGB and U-Venus filters, overall image sharpness is significantly enhanced and details of planets in different bands are taken. This filter makes it also possible to image some planets during daylight due to the dark background sky created by the 685nm IR Pass Filter.

Technical Data:

  • Schott optical substrate
  • 1.25” mounted (2mm+/-0.05mm)
  • Surface Quality: 60/40 (Refer to MIL-O-13830)
  • Both sides fine-optically polished to ensure accurate 1/4 wavefront
  • 30 arcsec parallelism

Filter Cell (specifications for cell mounted filters only):

  • 1.25” (M28.5*0.6)
  • Ultra-thin filter cell to minimize vignetting by maximized possible clear aperture
  • Black Anodized Finish
  • Non-Fading Laser Engraving

Available Sizes:

  • Mounted: 1.25” (2mm thickness)

Not recommended for:

  • Solar Observing and imaging
  • Visual observation

Serious eye damage will result if you fail to observe the warning.

In the box:

1 pc IR-Pass 685nm filter in a Plastic case

ANTLIA IR-Pass 685nm Planetary Imaging Filter - 1.25"