Astronomik Hydrogen-Alpha Imaging Filter

A 12nm bandwidth is a 'narrowband' specification that allows only a very specific slice of light—the Hydrogen-Alpha line—to pass through. This effectively isolates the signal from nebulae while blocking the vast majority of light pollution, making it possible to capture deep-sky objects even from suburban locations.

No, you shouldn't need to. This filter is parfocal with other filters in the Astronomik series, meaning they are designed to have the same optical thickness. You can switch between them during your imaging session without needing to adjust your focus.

While this filter is designed for dedicated CMOS and CCD astronomy cameras, it can be used with a DSLR or mirrorless camera if you have the appropriate adapter or filter drawer. However, keep in mind that standard color cameras are less sensitive to Hydrogen-Alpha light than monochrome astronomy cameras, so your results may vary.

This is a standard 2-inch mounted filter with an M48 x 0.75 thread. As long as your filter wheel, drawer, or eyepiece adapter accepts standard 2-inch threaded filters, it will fit your existing equipment.

The filter features a durable, scratch-resistant MFR coating designed to withstand the rigors of outdoor use. It is built to resist aging and humidity, so you don't have to worry about the optical performance degrading over time with proper care.

This is strictly an imaging filter. Because it blocks so much light to isolate the Hydrogen-Alpha wavelength, the view through an eyepiece would be extremely dark and generally not useful for visual astronomy.