Antlia OIII 4.5 nm EDGE Filter 2 inch Mounted

Antlia OIII 4.5 nm EDGE Filter 2 inch Mounted

Description

The Antlia OIII 4.5 nm EDGE filter is a narrowband filter designed for deep-sky imaging of nebulae emitting in the OIII line at 500.7 nm. Its 4.5 nm full width at half maximum and OD5 blocking eliminate unwanted wavelengths while maintaining more than 85 % peak transmission.
This design ensures high contrast and clean images even under light-polluted skies or when the Moon is present. The steep spectral profile minimizes halos around bright stars, and the single optical substrate removes internal reflections. The edge blackening prevents stray light and enhances optical reliability.
The Antlia EDGE filter is suitable for systems as fast as f/3 with minimal signal loss. It is intended exclusively for astrophotography and must never be used for solar or visual observation.

Technical Specifications

• Manufacturer: Antlia

• Product: OIII 4.5 nm EDGE Filter 2 inch mounted

• Type: narrowband OIII filter

• Central wavelength (CWL): 500.7 nm

• Full width at half maximum (FWHM): 4.5 nm

• Peak transmission: > 85 %

• Out-of-band blocking: OD5 (300–1000 nm)

• Optical substrate: single, non-glued

• Filter thickness: 2 mm ± 0.05 mm

• Surface quality: 60/40 (MIL-O-13830)

• Transmitted wavefront: λ/4 or better

• Parallelism: < 30 arcsec

• Filter mount: 2 inch (M48 x 0.75)

• Clear aperture: 48 mm

• Net weight: approx. 0.01 kg

• Application: astrophotography of OIII emission objects

• Not recommended: solar imaging, visual observation