Astronomik IR-Block 1.25" — infrared-blocking filter for lunar and planetary imaging The Astronomik IR-Block filter is Astronomik's standard filter for lunar and planetary imaging with infrared-sensitive cameras. It blocks infrared light while preserving the visible spectrum.
Manufacturer model: Astronomik IR-Block 1,25" (M28,5), 10230125 · Specifications checked against manufacturer data on 2026-11-03
The Astronomik IR-Block filter is Astronomik's standard filter for lunar and planetary imaging with infrared-sensitive cameras. It blocks infrared light while preserving the visible spectrum.
Telescopes corrected for visible light often focus infrared at a slightly different point, which adds a blurred ghost image to the sharp one. Many planetary cameras are sensitive to infrared, so blocking it removes halos and gives a sharper overall image. The filter works at all focal ratios.
Placed in front of the camera, the filter also protects the telescope and camera from dust and airborne contaminants. For visual observing, Astronomik considers it useful only as dust protection.
| Function | Infrared blocking; visible spectrum passed |
|---|---|
| Typical transmission | 97–99% |
| Focal ratio | Suitable for all focal ratios |
| Best use | Webcam and video imaging of the Moon and planets |
| Manufacturer code | 10230125 |
|---|---|
| Format | 1.25-inch cell, M28.5 × 0.6 thread |
| Glass thickness | 1 mm |
| Parfocal | With other Astronomik filters |
| Made in | Germany |
Astronomik IR-Block 1.25" product page
IR-Block (10230125), not the L-1/L-2/L-3 UV-IR Block luminance filters. Cut-off wavelength not published on the product page.