ALP-T Dual Band Filter (Ha-OIII) 5nm 2" - Antlia
The Antlia ALP-T 5nm dual-band filter is designed for use primarily with color sensors for one-shoot color (OSC) shooting such as color astronomy cameras or digital cameras. It can also be used as a narrow band filter for monochrome cameras to save imaging time.
The advanced multi-coatings of the ultra dual-band ALP-T filter effectively isolates H-Alpha red light and OIII blue-green light from emission nebulae, with almost complete suppression of optical density (OD) 4.5 over long distances. unwanted waves from light pollution, moonlight and skylight. The result is that the ALP-T dual-band 5nm filter creates a higher signal-to-noise ratio and better contrast in your images.
This filter allows you to capture the 2 main emission bands of nebulae at the same time, while removing unwanted signals. The raw materials are thus cleaner and therefore require less post-processing. As the Antlia ALP-T dual band 5nm filter appears golden yellow to the naked eye, it is also called a "Golden filter".
Applications and performance
Designed specifically for use with DSLR, CMOS and CCD color cameras. Suppressing optical density (OD) 4.5 on unwanted visual wavelengths increases the signal-to-noise ratio
Clean cuts of extremely steep lines minimize internal reflections
Ion gun-assisted deposition coating technology on the double-sided polished substrate, making it the most consistent and precise light pollution suppression filter
Good performance at focal ratios above F/3, with contrast increasing with focal ratio
Designed to suppress artificial lighting from Bortle scale 1 to 8. Near IR (NIR) is blocked up to 1100nm
Features
- Mounting diameter: 50.8mm screw (M48)
- Substrate thickness: 2mm
- Transmission:
- 90% transmission on the H-Alpha 656.3nm line
- 82% transmission on the O-III 500.7nm line
- Treatments: Filter polished on both sides with a precision of λ/4
- Multi-layer and anti-reflection treatment on both sides