Optolong O-III 6.5nm Filter

Use the Optolong O-III 6.5nm filter with the H-alpha and SII-CCD extra narrowband filters (SHO Set) for tricolor CCD astrophotography
Narrowband imaging with a SHO filter set can be done with the moon up in heavy light pollution, allowing you to image much more frequently that would otherwise be possible.
Hubble palette images can be made by combining H-alpha, OIII-CCD and SII-CCD images into a color rendering, such as the famous "Pillars of Creation" (M16 Eagle Nebula)

• Fine-optically polishing for double-sides-- Ensure accurate λ/4 wavefront and <30 seconds parallelism over the both surfaces
• Ultrasonic wave cleaning substrate with purified water to remove impurities and dust effectively
• IRO source assisted coating - For durability and resistance to scratching, as well as stability on CWL (central wavelength).  No deviation from temperature change.
• Constant stringent quality testing processes - Each filter is tested by spectrophotometer and laser interferometer testing spectrum and wavefront to ensure market filter is qualified product
• Optolong will spare no effort to serve our customer with outstanding quality products and best service!

Specifications

FWHM: OIII 6.5nm
Tpeak: <85%
Optical Density: OD 3
Surface Quality: 60/40
Transmitted Wavefront RMS: λ/4
Parallelism(arcsec): 30s