This is a great seven piece filter kit from Optolong. Building on the LRGB H-alpha telescope filter Kit this kit includes a SII and an OIII filter.
The SII-CCD 6.5nm Deep Sky Imaging Filter:is an extra narrowband SII-CCD 6.5nm filter (Sulfur II for CCD) is designed for nebula observation allowing 6.5nm bandwidth of light centered on a wavelength of 672nm 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 6.5nm Deep Sky Imaging Filter:
This filter is an extra Narrowband OIII-CCD 6.5nm filter. It is designed for nebula observation allowing 6.5nm bandwidth of light centered on a wavelength of 500nm 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 495.9nm 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)
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 589nm and improves color 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 color space is available with LRGB filter set and mono CCD camera.
The H-alpha 7nm Deep Sky Imaging Filter:
H-Alpha 7nm filter is the most popular narrowband filter allowing 7nm bandwidth of light centered on a wavelength of 656nm 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). 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
- 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
- 95% transmission at bandpass with the LRGB filters
- The Ha, SII, and OIII filters have 80% transmission, the H-alpha line is 656nm, the SII line is 672nm, and the OIII line is 500nm
- Infrared wavelength 700 to 1100nm 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 (clear aperture is 26mm for 1.25-inch; 45mm for 2-inch)
- Aerometal Material
- Precise CNC Machining
- Sand Blasting Process
- Black Anodized Finish
- Extinction Treatment to Prevent Reflection
- Laser Engraving No Fading