Bester H-alpha-Linienfilter für die Astrofotografie von Emissionsnebeln mit höchstem Kontrast und der Wiedergabe zartester Nebeldetails.
♦ schmalbandiger (<=7 nm) Linienfilter für wichtige Nebellinie
♦ bevorzugt für CDD-Kameras mit Full-Frame-Transfer-Technik
♦ 2 mm dick und somit homofokal mit vielen anderen Filtern von Optolong
♦ Interferenzfilter
♦ feinoptisch poliert
♦ mehrschichtig hartvergütet - reflexfrei und weitgehend kratzfest
Specifications
- CWL(centre wavelength): 656.3nm
- Fwhm: 7nm
- Tpeak: <85%
- Coating Wavelength: 300-1100nm
- Optical Denisity: OD3
- Surface Quality: 60/40
- Transmitted Wavefront RMS: λ/4
- Parallelism (arcsec): 30s
Reference Spectrum
Manufactruring Technique
- Fine-optically polishing for double-sides—— Ensure accurate λ/4 wavefront and <30 seconds parallalism over the both surfaces
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Ultrasonic wave cleaning substrate with purified water—— Cleanup by 13 purified water tank to remove inpurities and dust effectively
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Iro source assisted coating—— For durability and resistance to scratching, as well as stability on CWL (central wavelength) no deviation affected by temperature change.
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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
Package Details
- Silver Cardboard Box
- Plastic PP Case
- Imported high pressure EVA case lining