William Optics STC ULTRA LAYER® ASTRO MULTISPECTRA FILTER 48mm (Free Shipping)

• The SLR lenses focal distance is recommended for 60mm or more.
• It is specially designed Astro-Adapter M48-M56 P0.75mm for telescope adapter connecting Astro filter. CNC Machining is used in precisely manufacturing metal parts. Anodizing Aluminium process could reduce the reflection of the image.
• STC Astro-Multispectra filter can reduce the interference from artificial lighting in the city, and enhance the wavelength of Hα, Hβ,OIII and SII.
• It is coated by the use of the IBAD (Ion-beam-assisted deposition) technology on Schott® B270 optical 2mm glass, working for higher durability and easy cleaning, and preventing aging variation in optical spectral characteristics due to temperature and humidity change.
• High-quality double-sided NANO Anti-smudge coating builds excellent performance on waterproof and grease-proof.
• Matte black anodized and Teflon-coated frame design eliminates flare and easy to install or remove from your lens.
• This product is an interference filter. Its spectrum characteristics will be subject to the incidence of incoming light. Directly shooting at a strong light would affect the image performance due to the light interference and reflection.

Product Details

STC Astro Multispectra filter is a general-purpose light pollution suppression filter designed to use with DSLRs cameras. It will effectively reduce the interference from artificial lightings, such as mercury and sodium street light, yet allow the important nebula emission lines to pass, thus enhancing the contrast of astronomical objects. Supporting by Dr. Wei-Hao Wang, it is improved to passing more than 95% of the light from the main spectral lines from emission nebula, such as the predominant Hydrogen-Alpha line at 656.3nm, the Oxygen III line at 495.9 & 500.7nm, and the Hydrogen-Beta line at 486.1nm. It is coated by the use of the IBAD (Ion beam-assisteddeposition) technology on Schott® B270 optical glass, working for higher durability andeasilycleaning. Since light pollution and airglow are filtered out with ASTRO filter, much more of the interesting wavelengths of the deep-sky object will be recorded in these longer exposures.