ALP-T Dual Band Ha OIII 5nm

The Antlia ALP-T Dual Band 5nm Ha OIII is a dual line-pass narrowband filter designed for one-shot color (OSC) cameras like DSLRs and astronomical CMOS cameras, and can also be used with monochrome cameras to save imaging time. The advanced multi-coatings effectively isolate red hydrogen-alpha and blue-green oxygen-III emission lines from nebulae while suppressing optical density (OD) 4.5 on unwanted wavelengths from light pollution, moonlight, and airglow, resulting in superior signal-to-noise ratio and contrast. This filter features Ion Gun Assisted Deposition coating technology with good performance at focal ratios slower than f/3.6, with contrast increasing as focal ratio increases, and is designed to suppress artificial lighting from Bortle scale 1 to 8. The filter captures fine nebula details with minimal star halos, indicating high-quality coatings.