Optolong Filtro OIII 6,5nm 36mm
El filtro OIII-CCD de 6.5nm de banda angosta extra está diseñado para la observación de nebulosas que permite un ancho de banda de 6.5nm centrado en una longitud de onda de 500nm, que corresponde a las líneas de emisión OIII, y reduce la transmisión de ciertas longitudes de onda de luz, específicamente las producidas por luz artificial incluyendo vapor de mercurio, y luces de vapor de sodio de alta y baja presión y la luz natural no deseada causada por la emisión de oxígeno neutro en nuestra atmósfera (es decir, brillo celeste).
OIII emits 495.9nm and 500.7nm and it is a blue-green colored filter. Many of images of planetary nebula and supernova remnants are taken only with H-alpha and OIII filters. They show great structural details, but have natural colors, looking like an RGB image.
Main Use and Performance
- Suitable for visual observation on most emission nebulae, planetary nebulae and supernova remnants
- Hubble look of images can be made by the combination of H-alpha, OIII-CCD and SII-CCD, such as the famous “Pillars of Creation” (M16 Eagle Nebula)
- Narrowband filter do not eliminate the effects of light pollution or increase the object’s brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.
- WARNING: The filters of Optolong are not designed for sun observation. DO NOT LOOK AT THE SUN WITH OPTOLONG FILTER. You would be BLIND if you fail to observe the warning.
Technical Data
- Schott substrate material
- Thickness 2.0mm
- Surface Quality: 60/40 (Refer to MIL-O-13830)
- Fine-optically polished to ensure accurate 1/4 wavefront and <30 seconds parallelism over the both surfaces
- 80% transmission at major OIII line 500nm
- Infrared wavelength 700-1100nm cut-off
- 0.1% transmission of off-band, specifically the major emission lines of artificial light pollution (i.e. Na 589nm, Hg 435nm and 578nm). Transmission of 0.1% is equivalent to OD3(Optical Density), and a high optical density value indicates very low transmission, and low optical density indicates high transmission.
Coating Parameter
- Non-cementing optical substrate coating
- Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL(central wavelength) no deviation affected by temperature change
- Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band
Filter Cell
- Ultra-thin filter cell minimize vignetting by maximize possible clear aperture (clear aperture is 26mm for 1.25”; 45mm for 2”)
- Aerometal Material | Precise CNC Machining | Sand Blasting Process | Black Anodized Finish | Extinction Treatment to Prevent Reflection | Laser Engraving No Fading
Package
- Plastic PP Case | Imported High Pressure EVA Case Lining | Silver Cardboard Box | High Density Sponge Carton Lining
Spectral Curve
