Baader Filters f/2 Ultra-Highspeed H-alpha/OIII/SII CMOS 50.4mm (70960)

H-alpha filters transmit light at a wavelength of 656nm and are the ideal choice for narrowband astrophotography. They provide high-contrast imaging and reveal rich details of nebulae, even in areas with significant light pollution.

OIII filters are narrowband filters designed specifically for nebula observation. They allow a 3nm bandwidth of light centered on a wavelength of 500nm, corresponding to OIII emission lines, while blocking all other light. These filters are excellent for isolating oxygen emissions in nebulae.

SII filters pass light at a wavelength of 672nm with a bandpass of 3nm, making them perfect for nebula photography. They are suitable for capturing most emission nebulae, planetary nebulae, and supernova remnants.

If you want to achieve the iconic look of Hubble Space Telescope (HST) images, such as the famous “Pillars of Creation” in the Eagle Nebula (Messier 16), the SII filter is a must-have addition to your collection after H-alpha and OIII filters. Like the H-alpha filter, the SII filter is a deep red filter near 672nm. Together, H-alpha, OIII, and SII filters enable tri-color narrowband imaging that creates the distinctive Hubble-like appearance for many emission nebulae. These filters can also be used during moonlit nights, ensuring your imaging sessions continue without interruption.

Specifications:

    Central Wavelength (nm): 656.3 (H-alpha), 500.7 (OIII), 671.7 (SII)
    Half-Value Width (nm): 3.5 (H-alpha), 4 (OIII and SII)
    Frame Type: Ring
    Mount Material: Aluminium
    Coating: Reflex-Blocker™
    Filter Thickness (mm): 2
    Filter Size (mm): 50.4

Compatibility and Applications:

    Appropriate for f/ratio: f/3.4 - f/1.8
    Type: Line filter
    Series: f/2 Ultra-Highspeed

Applications:

    Useful for photographs: Yes
    Visually useful: No
    Twin stars, Moon & Planets: Not suitable
    Nebulae & Galaxies: Ideal

These H-alpha, OIII, and SII filters are essential tools for astrophotographers seeking to create stunning tri-color narrowband images with exceptional detail and contrast while minimizing interference from light pollution or moonlight.