Astronomik OIII CCD Filter

A 12nm bandpass is narrow enough to effectively block out light pollution and airglow while still allowing enough signal through for shorter exposure times. It provides a great balance between high contrast and manageable integration times for CCD sensors.

While this filter is optimized for CCD imaging, it performs well with many modern CMOS cameras. However, if you are using a camera with a very small pixel size or high sensitivity, you might consider if a narrower bandpass is required for your specific light-pollution levels.

This is a 50mm round unmounted filter. You will need a filter wheel or drawer that accommodates 50mm round glass, as it does not come in a threaded cell for standard eyepiece or lens attachments.

Because this filter isolates a specific wavelength of light, it will not produce a natural-color image on its own. You will typically combine data from this filter with H-alpha and SII filters to create a 'Hubble Palette' or other narrowband composite images.

This filter is specifically designed for planetary nebulae and supernova remnants that emit strongly in the OIII line. It is an essential tool for pulling out fine, gaseous structures that are often washed out in broadband imaging.