Baader O-III 2" unmounted f/2 Highspeed Filter 4 nm CMOS optimized (2961453U)

Baader O-III 2" unmounted f/2 Highspeed Filter 4 nm CMOS optimized (2961453U)

Description

The Baader O-III 2" unmounted (Ø 47.4 mm, 2 mm thick) f/2 Highspeed Filter 4 nm is designed for extremely fast optical systems such as the Celestron RASA f/2 astrographs. It is specially selected for Baader FCCT (Filter Changer Camera Tilter) filter sliders, compatible with QHY cameras and similar models.

Optimized for CMOS sensors, it also performs excellently with CCD technology. With a central wavelength of 500.7 nm and a 4 nm bandwidth, it isolates the O-III emission line, providing maximum contrast even under strong light pollution (Bortle 9 to 6). It reduces star size and highlights the finest nebula details in O-III astrophotography.

Featuring precision planeoptical polishing and Reflex-Blocker™ hard coating, it minimizes unwanted reflections. Blackened edges with telescope-side indicator ensure proper orientation, while Life-Coat™ sealed protection guarantees long-term durability. Lightweight (0.01 kg) and robust, it is sold individually and is indispensable for high-speed O-III astrophotography.

Technical Specifications

• Manufacturer: Baader Planetarium

• Product SKU: 2961453U

• EAN code: 4047825051011

• Net weight: 0.01 kg

• Filter type: O-III f/2 Ultra Highspeed

• Mount: unmounted

• Shape: round

• Diameter: 47.4 mm (2" without cell)

• Thickness: 2 mm

• Central wavelength (CWL): 500.7 nm

• Half bandwidth (HBW / FWHM): 4 nm

• Transmission: O-III line

• Coating: Reflex-Blocker™ hard coated, planeoptically polished

• Durability: Life-Coat™ sealed edges

• Edges: blackened with telescope-side indicator

• Suitable f/ratio: < f/2.3

• Compatibility: Celestron RASA 8", Baader FCCT, QHY cameras, CMOS and CCD

• Application: O-III astrophotography, nebulae, light-polluted skies

• Packaging: single filter