Description
Optolong LRGB Ha, S2 & OIII Astroimaging Filter Kit – 2 inch
Please note this is a 2 inch diameter round mounted astroimaging set of filters to fit directly to all standard CCD 2 inch Colour Filter Wheels which are commonly used globally by nearly every major CCD Manufacturer globally.
This is a premier quality Seven (7) piece filter kit from premier specialist astronomy & astroimaging filter manufacturer Optolong.
The SII-CCD 6.5 nm Deep Sky Imaging Filter: is an extra narrowband SII-CCD 6.5 nm filter (Sulphur II for CCD) is designed for nebula observation allowing 6.5 nm bandwidth of light centered on a wavelength of 672 nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
Main Use and Performance
- Use with H-alpha and OIII-CCD extra narrowband filters (SHO Set) for tricolor CCD astrophotography
- Narrowband imaging with SHO set can be done with the moon up in heavy light pollution, so your equipment is not sitting dormant for several weeks
- 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.
OIII-CCD 6.5 nm Deep Sky Imaging Filter:
This filter is an extra Narrowband OIII 6.5 nm filter. It is designed for nebula observation allowing 6.5 nm bandwidth of light centered on a wavelength of 500 nm through, which corresponds to OIII emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
OIII emits 495.9 nm and 500.7 nm and it is a blue-green coloured 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 colours, 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)
The LRGB filter set:
This set divides the spectrum into its components red, green, blue and luminance.
OIII emission overlaps on blue and green filters with maximum transmission to allow high efficiency and natural color imaging. Gap between green and red filters serves to block out the primary Sodium light pollution line at 589 nm and improves colour balance and separation.
Main Use and Performance
- Work well with debayered monochrome CCD cameras
- Suitable for deepsky and planetary CCD imaging
- RGB-imaging allows equal weighting factors for each channel, very important for automated imaging.
- The ideal raw material for image processing in the sRGB colour space is available with LRGB filter set and mono CCD camera.
The H-alpha 7 nm Deep Sky Imaging Filter:
H-Alpha 7 nm filter is the most popular narrowband filter allowing 7 nm bandwidth of light centered on a wavelength of 656 nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapour, and both high and low pressure sodium vapour lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). Best choice of narrowband H-alpha astrophotography filter for highest contrast and revealing subtle nebula details.
Main Use and Performance
- Suitable for viewing on faint emission nebula of H-Alpha line in full moonlight or in severe light pollution
- 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 imaging with SHO set (H-alpha, OIII-CCD and SII-CCD) can be done with the moon up in heavy light pollution, so your equipment is not sitting dormant for several weeks
- H-alpha filter is the first narrowband addition to LRGB set for most imagers who blend a black-and-white Ha image into RGB data to enhance structural detail while maintaining natural look
- 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.
Features of the Full Kit:
Technical Data
- Premier German Schott substrate material
- Thickness 2.0 mm
- 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
- 95% transmission at bandpass with the LRGB filters
- The Ha, SII, and OIII filters have 80% transmission, the H-alpha line is 656 nm, the S2 line is 672 nm, and the OIII line is 500 nm
- Infrared wavelength 700 to 1100 nm cut-off
- Precision off-band blocking
Coating Parameter
- Multi-layers anti-reflection coating
- 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
- Aerometal Material
- Precise CNC Machining
- Sand Blasting Process
- Black Anodized Finish
- Extinction Treatment to Prevent Reflection
- Laser Engraving No Fading