SII 7nm Pegasus filter - 2″ mounted

Pegasus Astro SII filter (Sulfur II)

The filter Pegasus Astro SII is a high-quality narrowband filter designed for astrophotography. Here are its detailed specifications:

Technical specifications

• Diameter : 50.8 mm (2 inches)
• Thread : M48 x 0.75 mm
• Total thickness : 7.5 mm (5 mm filter body + 2.5 mm thread)
• Glass thickness : 2 mm
• Bandwidth : 7 nm
• Center wavelength: 672 nm
• Transmission : Tave > 80% at 672 nm
• Polishing : 1/4 wavelength
• Coating : Anti-reflective multilayer
• Type : Narrow-band interference filter

Features and benefits

• Optimum transmission : Le filtre offre une transmission supérieure à 80% à la longueur d’onde centrale de 672 nm, correspondant aux raies d’émission du soufre doublement ionisé (SII).
• Narrow bandwidth : Avec une bande passante de seulement 7 nm, ce filtre isole efficacement les raies d’émission SII, permettant une excellente séparation des détails spectraux.
• Parafocality: Le filtre SII est parafocal avec les autres filtres Pegasus, simplifiant le processus d’acquisition d’images.
• Superior optical quality : The 1/4-wavelength polish ensures excellent image quality and optimal sharpness.
• Anti-reflective coating : Multi-layer anti-reflective coating eliminates halos, ghosting and unwanted reflections.
• Durability: The filter is designed to withstand scratches and temperature changes.
• UV and IR blocking : The filter effectively blocks UV and IR wavelengths, improving image sharpness and reducing halos.

Astrophotography applications

• Nebula imaging : Ideal for capturing the details of nebulae rich in ionized sulfur.
• Reducing light pollution : The narrow bandwidth allows for effective imaging even in areas with high light pollution or during a full moon.
• False color imaging : Used in the Hubble palette technique (SHO) to create spectacular false-color images.
• High-resolution imaging : The narrow bandwidth produces high-contrast images that reveal fine details in nebular structures.

Reference and Configuration

How do I check for compatibility?

Before setting up your system, compare the exact part number, generation, and connection types of your equipment with the manufacturer’s documentation. An accessory from a different generation is not necessarily interchangeable.

Documentation: Pegasus Astro, manufacturer information. To verify a specific assembly, provide the part number PEG-FLTR-2M-S2 to Deep Space Astronomy.