Chroma Technology Bessell U Filter

This is a photometric filter, specifically engineered for ultraviolet light applications. It is optimized for capturing data within the 320 nm to 397 nm range, making it ideal for scientific observation and precise light measurement.

No, you shouldn't need to. The filter features a parfocal design, meaning it is built to match the focal length of other standard optical components in your setup, allowing for seamless transitions during your imaging session.

The rear surface is treated with anti-reflection coatings specifically designed to minimize internal reflections. This helps prevent ghosting artifacts, ensuring your final images remain clean and high-contrast.

Yes, this filter is compatible with focal ratios of f/4 or smaller. Its construction is robust enough to maintain performance even in these faster optical systems.

Not significantly. The filter uses sputtered hard coatings on a single substrate, which makes the passbands highly resistant to shifts caused by temperature or humidity fluctuations. You can expect consistent spectral stability throughout the night.

Yes, by using a single piece of glass rather than multiple laminated layers, the filter is less prone to delamination over time. This construction method, combined with the hard coatings, results in a more durable and reliable optic for long-term use.