Astronomik Filters 2" OIII filter

Reveal Subtle Nebula Structures

Narrowband filters redefine the benchmarks for imaging and research, offering unparalleled performance and durability.

They excel in enhancing the contrast of emission targets by effectively reducing background noise. With a guaranteed transmittance of over 90% at the emission wavelength, these filters ensure maximum signal strength. Known for their ability to minimize halos around bright stars, even during lengthy exposures typical of narrowband astrophotography, these filters are meticulously coated to the edge and edge blackened to minimize any stray light. This is crucial for a filter that selectively blocks most light except for the narrow bandpass.

When it comes to imaging, narrowband filters prioritize contrast. This is essential for bringing out faint features by minimizing background noise. Our filters maintain a consistent signal percentage at the emission line, ensuring reliable performance even with narrower bandwidths. While achieving this level of performance comes at a higher manufacturing cost, it enables you to fully leverage the improved contrast compared to less expensive filters on the market. The enhanced contrast is clearly demonstrated in a series of equal-exposure images of the Crescent Nebula (NGC 6888) taken on the same system and on the same night. As the bandwidth narrows, the nebula and surrounding nebulosity become more pronounced.

The specifications of these filters include:

Capacity: Filters

Connection (to the telescope): 2"

Coating of Optical System: Multiple

Mount Material: Aluminum

Frame: 2"

Series: OIII

Type of Build: Line Filter

Area of Application: Visually Useful, Useful for Photographs, Anti Light-Pollution