Baader Filters OIII CMOS f/3 Ultra-Highspeed 1.25" (75577)

OIII filters allow only light with a wavelength of 501 nanometers to pass through. This corresponds to the spectral lines of doubly ionized oxygen, which are emitted by planetary nebulae and some emission nebulae. By blocking out other wavelengths, these filters enhance contrast and make faint nebulae visible for the first time.

Astrophotography benefits greatly from OIII filters, which are best used with monochrome cameras. For optimal results, images captured with OIII filters should be combined with those taken using H-alpha and SII filters. This combination produces high-contrast images that clearly depict faint nebulae in stunning detail.

Specifications:

    Central Wavelength (nm): 500.7
    Half-Value Width (nm): 4
    Frame Size: 1.25"
    Mount Material: Aluminium
    Coating: Reflex-Blocker™
    Connection (to Telescope): 1.25"
    Filter Thickness (mm): 2

Compatibility and Applications:

    Appropriate for f/ratio: f/3.4 - f/2.3
    Type: Line filter
    Series: f/3 Ultra-Highspeed

Applications:

    Useful for photographs: Yes
    Visually useful: No
    Nebulae & Galaxies: Yes
    Moon & Planets: No

These OIII filters are essential tools for astrophotographers aiming to isolate oxygen emissions and capture high-contrast, detailed images of nebulae while minimizing interference from surrounding light sources.