Baader Filters f/2 Highspeed SII CMOS 50.4mm

The SII filter: A narrowband S-II 7nm filter, designed for nebula photography, selectively transmits light at a wavelength of 672nm with a bandpass of 3nm.

It proves suitable for capturing most emission nebulae, planetary nebulae, and supernova remnants.

If you aspire to replicate the captivating aesthetic of Hubble Space Telescope (HST) images, such as the renowned “Pillars of Creation” (the Eagle Nebula, Messier 16), the SII (es-two) or sulfur filter is an essential addition to your collection, following H-a and OIII. Much like the H-a filter, the SII filter operates in the deep red spectrum around 672 nm. Employing H-a, OIII, and SII filters collectively imparts that distinctive Hubble-like appearance to many emission nebulae. Moreover, undertaking tri-color narrowband imaging with these filters remains feasible even when the moon is present, ensuring your equipment stays active throughout.

SPECIFICATIONS

Capacity

Central wavelength (nm): 671.7

Half-value width (nm): 6.5

Frame: Ring

Mount material: Aluminium

Coating of optical system: Reflex-Blocker™

Appropriate for: f/3.4 - f/1.8

Filter thickness (mm): 2

Filter Size (mm): 50.4

General

Type: Filters

Type of build: Line filter

Series: f/2 Highspeed

Area of application

Useful for photographs: Yes

Visually useful: No

Twin stars: No

Moon & Planets: No

Nebulae & galaxies: Yes