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Optolong 3nm SHO 2" Mounted Filter Kit

(Only 1 Left)
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SKU: OTL-SHO3-KIT-200
$1,199.00

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Optolong 3nm Filter Kit - 2" Mounted

This Optolong SHO Filter kit comes with 2" 3nm H-alpha, SII, and OIII filters. Adding this filter kit to your astrophotography setup will give you higher contrast, greater detail, decreased background noise, and increased faint nebula signal. The SHO 2" filter kit works best with monochrome cooling CCD astronomy cameras and modified DSLR imaging in each channel. The HA, OIII, and SII correspond with the RGB channel, allowing imagers to process Hubble images with post-processing astrophotography software.

About the SHO Filters

About the H-alpha Filter

This Optolong H-alpha filter is narrowband and allows 3nm bandwidth of light, centered on a 656nm wavelength, through. It reduces certain types of light transmission like artificial light from mercury vapor and both high/low pressure sodium vapor lights. It also blocks natural light transmissions caused by neutral oxygen emission in our atmosphere, often called sky glow. This popular type of filter is perfect for those looking to have better contrast and the ability to capture subtle nebula details.

About the OIII Filter

OIII (Oxygen IIII) CCD filters like this 2" Optolong OIII extra narrowband filter, is great for blocking unwanted light, both artificial light and natural sky glow. This particular filter allows 3nm bandwidth of light, centered on a 500nm wavelength, through. This corresponds with the OIII emission line. OIII filters emit 495.9nm and 500.7nm and are blue-green colored filters. When coupled with the H-alpha filter, users will get incredible images with great structural details and natural colors, like with an RGB image. With the coating optimization, Optolong has ensured that this filter does well with bright stars after performing a qualitative halo test.

About the SII Filter

The SII (Sulfur II) CCD filter is an extra narrowband filter and designed for nebula observation. The SII filter from Optolong allows 3nm bandwidth of light centered on a wavelength of 672 nm though. Like the OIII and the H-alpha filters, the SII filter reduces transmission of certain light wavelengths, particularly those that are produced by artificial light and natural light/sky glow.

About the Coating Technology

Optolong uses a multi-layer, anti-reflection coating on each of the three filters. Each filter uses a non-cementing optical substrate coating, which is applied through precision Ion-based deposition, providing durability and resistance to scratching. It also provides stability on the central wavelength so there is no deviation depending on temperature change. Their planetary rotation system gives precision and homogenous coatings to ensure high-value pass-band transmission and off-band optical density.