Chroma O-III Imaging Filter

This filter is designed to isolate the 500.7nm emission line of doubly ionized oxygen. It is specifically used in astrophotography to capture high-contrast, detailed imagery of nebulae by blocking out unwanted light pollution and other wavelengths.

This specific filter is optimized for telescopes with focal ratios of f/4 or slower. If you are using a faster system, you may experience a shift in the central wavelength, which can reduce the filter's effectiveness.

By using a single piece of glass rather than laminated layers, this filter eliminates the risk of internal reflections and delamination over time. This construction ensures better spectral stability and helps maintain high contrast in your final images.

The rear anti-reflection coating is crucial for minimizing ghosting and internal reflections. It ensures that the maximum amount of light passes through the filter to your sensor, resulting in cleaner, sharper images.

The filter uses sputtered hard coatings, which are exceptionally durable and resistant to environmental stress. It is engineered to maintain its spectral performance even when exposed to significant fluctuations in temperature and humidity.