Astronomik Filters CLS Nikon XL Clip (66927)

The Nikon Clip Filters have been successfully tested with the D750, D780, D800, and D810 camera models. Compatibility with other Nikon bodies has not yet been verified.

Astronomik CLS Filter
The Astronomik CLS is an affordable filter designed for black-and-white photography, CCD imaging, and visual observation of nebulae, galaxies, and star clusters. It works with astronomical instruments of any size. Since 2008, all Astronomik filters have been redesigned to eliminate halos and unwanted reflections for improved performance.

Light Pollution Reduction
This filter effectively blocks spectral lines from mercury and sodium-vapor lamps while allowing most visible light and H-alpha emissions to pass through. It preserves important emission lines and enhances contrast by reducing light pollution. The spectral range visible to dark-adapted eyes is also transmitted, making it ideal for astrophotography and visual observation.

Optimized Usage
The Astronomik CLS filter is optimized for aperture ratios between 1:3 and 1:15. Transmission losses and chromatic distortions are minimal unless used with extremely bright aperture ratios (e.g., 1:2 or higher). It is suitable for telescopes of all aperture sizes.

Applications

• Photography: Suitable for DSLR cameras (modified or unmodified), CCD cameras, and black-and-white film photography.
• Visual Observation: Effective in dark-sky conditions to reduce light pollution but less suitable for urban skies.

Technical Specifications

• 92% transmission at 486nm (H-beta)
• 92% transmission at 496nm (OIII)
• 92% transmission at 501nm (OIII)
• 97% transmission at 656nm (H-alpha)
• Passes light from 450–540nm and beyond 650nm.
• Glass thickness: 1mm with multiple coatings for added durability.

Build Quality and Compatibility
The filter features an aluminium mount in a clip-filter frame format. It is resistant to scratches, humidity, and aging effects, ensuring long-term reliability. Astronomik CLS filters are parfocal with other Astronomik filters, maintaining excellent optical performance. They are delivered in a durable plastic storage box for safe handling and protection.