Camera Lens Filter Set Telescope Monocular Astrophotography CCD Ultrasonic DSLR

Description

Camera Lens Filter Set Telescope Monocular Astrophotography CCD Ultrasonic DSLR
Specifications
Tave: T>98%
Spectrum: 300-700nm
Optical Density:  OD3
Surface Quality: 60/40
Transmitted Wavefront RMS: λ/4
Parallelism (arcsec): 30s
Manufacturing Technique
Fine-optically polishing for double-sides—— Ensure accurate λ/4 wavefront and <30 seconds parallalism over the both surfaces
Ultrasonic wave cleaning substrate with purified water—— Cleanup by 13 purified water tank to remove inpurities and dust effectively
Iro source assisted coating—— For durability and resistance to scratching, as well as stability on CWL (central wavelength) no deviation affected by temperature change.
Constantly stringent quality testing processes—— Each filter was tested by spectrophotometer and laser interferometer testing spectrum and wavefront to ensure market filter is qualified product