Antlia IR Pass Filter (685nm) - 1.25"

Our #: OFIL-AF-IR685-1.25in
Mfg #: IR685-1.25in
Our Price: $39.00
Free shipping for this item in the US
More Info

Contiguous US Customers:
All items we sell ship for free within the Contiguous US. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. During checkout, you may also be shown other optional faster shipping choices.

US Customers in Hawaii and Alaska:
Free shipping applies to almost all products. A few large telescopes and mounts are excluded from this free shipping offer. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.

International Customers:
Free shipping does not apply to international orders. During check-out, you will be presented with several shipping choices and costs. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions.

In Stock (5 Available)
Stock listed above is accurate & shown in real time
Ships by Next Business Day

Product Details

The Antlia IR Pass 685nm filter is an absorptive filter that allows infrared light with wavelengths of more than 685nm to pass through. 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), result in the sharpest and highest contrast image 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. The filter is also possible to image the other 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 (MIL-O-13830)
  • 2 Sides Fine-optically polished to ensure accurate 1/4 wavefront
  • 30 arcsec parallelism

Filter Ring:

  • 1.25” (28.5x0.6)
  • Ultra-thin filter cell to minimize vignetting by maximize possible clear aperture
  • Black Anodized Finish
  • Laser Engraving No Fading

Not Recommended:

  • Solar Observing and imaging
  • Visual observation
  • DO NOT LOOK AT THE SUN WITH ANTLIA FILTERS.
  • Serious eye damage will result if you fail to observe the warning

Useful Resources

Filter Cell Specifications

D = Filter Cell Diameter = 31.5mm / 1.24"

T = Total Filter Height = 7.3mm / 0.28"

C = Filter Cell Height (Excluding Male Thread) = 4.7mm / 0.18"

M = Male Thread Length = 2.5mm / 0.09"

F = USABLE Female Filter Thread Length = not threaded

S = Glass Substrate Thickness = 2mm / 0.07"

CA = Clear Aperture = 25.5mm / 1.00"

 

Other Information

  • Country of Manufacture: China