The Antlia OIII 7nm Prime narrowband filter delivers a finely tuned 7nm FWHM (Full Width at Half Maximum), balancing high signal transmission with effective suppression of unwanted wavelengths. Its bandwidth allows strong signal capture while reducing background noise and the impact of light pollution.

Antlia incorporates the same advanced optical coatings found in its 3nm Pro series, ensuring the 7nm Prime filter produces high contrast and an excellent signal-to-noise ratio (SNR). At the key OIII emission line of 500.7nm, the filter transmits 90% of the signal—making it easy to reveal faint, delicate details in oxygen-rich nebulae.

By blocking out-of-band light to OD4 levels (0.01%), the filter cuts stray light and prevents interference from nearby spectral lines. Its sharp spectral edges reduce halos around bright stars, preserving clarity in your final image.

You can use the Antlia 7nm Prime filter with fast optical systems down to f/2, without significant signal loss. Its design supports a wide range of imaging setups, from refractors and Newtonians to RASAs and other fast scopes.

Whether you’re shooting under dark skies or in light-polluted areas, the Antlia OIII 7nm Prime filter helps you capture deep-sky objects that shine in the OIII wavelength—such as emission nebulae, planetary nebulae, and supernova remnants—with impressive detail and contrast.

Application and Performance:

• Transmits 90% of light at the central OIII wavelength of 500.7nm, capturing maximum signal from faint nebulae

• Handles fast optics down to f/2 with minimal signal loss, making it ideal for high-speed systems

• Maintains sharp star profiles with a steep spectral curve that minimizes halos around bright stars

• Uses a single glass substrate to prevent internal reflections and preserve image clarity

• Targets a wide range of narrowband objects, including OIII emission nebulae, planetary nebulae, Wolf-Rayet regions, and supernova remnants

• Performs reliably in both light-polluted environments and dark-sky locations

• Features edge-blackened unmounted filters to block stray light and suppress internal reflections

• Delivers high optical reliability, reducing the need for heavy post-processing

• Enhances detail and contrast in deep-sky objects rich in OIII emissions

Not recommended for:

• Solar imaging

• Visual observation at night