OPTOLONG H-Alpha 7nm SII-CCD 6.5nm OIII-CCD 6.5nm Narrow-Band Filters kit  for Deep Sky 2" Mounted

1. These Optolong 2” Filters are made with advanced glass that has been multi-coated with an ion-assisted deposition technology to ensure scratch resistance and stability on the central wavelength, or CWL. The filter cell is made of lightweight, strong metal and is CNC machined, sand-blasted; black anodized, and then laser engraved.

2. The Optolong H-Alpha 7nm is an extremely narrow emission-line filter that works by allowing a 7nm bandwidth of light, centered on the 656nm wavelength through, and blocking the transmission of contrast-killing light pollution wavelengths. Wavelengths that are responsible for natural light pollution, or skyglow, are drastically reduced, as is artificial light pollution caused by high and low pressure sodium vapor and mercury vapor lights. The result is a high contrast image that reveals the H-alpha line in all its glory.

3. The Optolong Sulfur II 6.5nm Extra Narrowband Filter transmits a 6.5nm bandwidth of light that is centered at 672nm and drastically reduces other transmissions, including wavelengths of light that are responsible for light pollution (both artificial and natural). Like all Optolong filters that are designated as “CCD”, this SII filter also blocks infrared wavelengths from 700nm to 1100nm so you don't need a separate IR-Cut filter.

4. The Optolong Oxygen III 6.5nm Extra Narrowband Filter transmits a 6.5nm bandwidth of light that is centered at 500nm and drastically reduces other transmissions, including wavelengths of light that are responsible for light pollution (both artificial and natural). Like all Optolong filters that are designated as “CCD”, this OIII also blocks infrared wavelengths from 700nm to 1100nm so you don't need a separate IR-Cut filter.

5. The Optolong 6.5nm SII filter can be used in conjunction with H-Alpha and OIII filters for false color emission line images like the Hubble Space Telescope.

Specturm curve

Quality Filter Materials:

1. CNC machined and black anodized aero-metal filter cell that is ultra-thin to provide largest clear aperture; Laser-engraved to prevent fading

2. Multiple layers of anti-reflection non-cementing coatings applied via electron-beam gun evaporation with Ion-assisted deposition

Filter Manufacturing Processes and Parameters:

1. Filter substrate is fine-optically polished to 1/4 wave and <30 parallelism over both surfaces

2. Surface quality, according to MIL-O-13830, is 60/40

3. 80% transmission at OIII line 500nm (at SII line 672nm; at H-alpha 656nm)

4. Infrared wavelength 700-1100nm cut-off

5. 0.1% transmission Hg at 435nm and 578nm

6. 0.1% transmission Na at 589nm

7. High value transmission of pass-band and optical density of off-band is assured through Optolong’s planetary rotation system, a homogenous and precise coating procedure

8. Each filter comes with a plastic case with high pressure EVA case lining   

                                                             Vela Supernova Remnant

                                   (SHO Set, H-alpha 7nm, OIII-CCD 12nm, SII-CCD 12nm)

Package Includes:

   l OPTOLONG 1.25/2inch H-Alpha 7nm Filter

l OPTOLONG 1.25/2 inch SII 6.5nm Filter

l OPTOLONG 1.25/2 inch OIII 6.5nm Filter

l Three Sturdy Plastic Cases

FAQ

1. Why do we need a light pollution suppression filter?

The astrophoto is more easily washed out by sky background, or overposed, which makes the longer exposure impossible. But we all know that it is important to expose your images so that faintest detail is not impacted by noise of your DSLR camera (CCD). Light  pollution filters are designed to block wavelengths of skyglow, and more generally light pollution, and passing other wavelengths(particular the nebula lines), thus allowing longer astrophoto exposures to be made filters blocking light pollution while not weaken signals of objects. It is true that longer exposure times with light pollution filters work while exposure effects will not change with or without filters.

2. Is it enough that only one filter work on all objects?

No. it isn't. Different filter has different degree of suppression.  Filter designed to select specific narrow emission lines may suppress broad parts of the spectrum, decreasing the light from broadband source even more than filters designed for balanced color photography.  Broadband filter such as L-Pro filter performance better than UHC filter for full spectrum objects. But for emission line objects and serious light pollution areas, UHC is a good choice.  

3.There is some problem with the product design. Could you help us to resolve the problem?

We are much appreciate supply you product design. With years of developing, we have much experience and own understanding of coating design according to different applications. There is much we could do for you.

4. Could Optolong support on prototype for sample offer?

There is no MOQ requirement for the prototype filters. We even could offer free samples for OEM according to the condition.

5. Could Optolong supply OEM for customer?

Yes, we could. Send us your data details which your requirement. Our technical engineer will design products for you. Furthermore, Optolong standard products also welcome.