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    Sale!
    Telescope-Accessories-Chroma Technology SII 3 nm Filter, 1.25" Mounted
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    Home / Astro Photography / Accessories

    Telescope-Accessories-Chroma Technology SII 3 nm Filter, 1.25″ Mounted

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    • Telescope-Accessories-Chroma Technology SII 3 nm Filter, 1.25″ Mounted 7

    $431.25 Original price was: $431.25.$172.50Current price is: $172.50.

    84 in stock

    Categories: Accessories, Astro Photography Tags: Accessories, arecibo radio telescope, Chroma Technology SII 3 nm Filter, 1.25" Mounted, hubble space telescope pictures, james webb telescope news, monocular telescope, sky telescope, Telescope, telescope lyrics carti, telescope near me
    • Telescope-Accessories-Chroma Technology SII 3 nm Filter, 1.25″ Mounted 8
    • Telescope-Accessories-Chroma Technology SII 3 nm Filter, 1.25″ Mounted 9
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    • Overview

    Experience the Unparalleled Excellence of the Chroma SII Filter!

    Looking to take your narrowband images to the next level? Look no further than this Chroma 3 nm SII filter! As an abundant element within emission nebulae, the ability to collect isolated data on sulfur is vital in creating colorful astrophotos with captivating layers of detail. Through the expertise from Chroma Technology, this 3 nm filter does a wonderful job at separating the background sky and the SII wavelength. The result? A revelation of outstanding structure within celestial bodies. Having an SII filter of this caliber is certain to make your Hubble Palette images pop!

    With decades of optical filter expertise at their side, Chroma Technology has designed this filter with high quality glass coated with sputtered hard coatings on both surfaces. These coatings eliminate ghosting, ensure maximum light transmission to your camera sensor, and provide exceptional longevity through resistance of humidity and temperature shifts. The 3 nm bandwidth is ideal for capturing stunning data on sulfur nebulosity, providing intense contrast on targets such as the Lagoon Nebula, the Dumbbell Nebula, the Rosette Nebula, and plenty more emission nebulae. Mounted within a 1.25” filter cell, this narrowband filter seamlessly integrates into your imaging train.

    ​

    horsehead nebula
    SII

    ​

    tadpoles nebula

    Why Choose Chroma?

    chroma logo
    • Chroma Technology, a 100% employee owned company founded in 1991, is an industry leader in development of precision-crafted optical filters. Their in-depth knowledge on filter construction and dedication to cutting-edge coating technology delivers unparalleled transmittance rates in the desired wavelength, something well apparent through the outstanding clarity and sharpness within the captured images! This highly reputable company stands out with their unrivaled expertise, developing filters that not only deliver performance beyond compare for amateur astronomy, but are designed with such dexterity that makes them well suited for terrestrial astronomy research applications. With both ISO 9001 and B Corporation certifications, Chroma Technology demonstrates their commitment to excellence—ensuring their filters not only meet, but exceed customer expectations.

    ​

    A Professional Grade Astrophotography Filter of the Highest Quality

    Let’s Check out the Stats!

    What exactly makes one filter better than another? How can I tell which filter will be best for my needs? To understand how well a filter performs, manufacturers provide what is called a transmission chart along with their filters. These charts give insight into the wavelengths allowed through, the bandpass, as well as the transmission percentage. It may be a bit confusing at first glance, but no need to worry, we have you covered! Our team of gear experts have crafted a comprehensive How to Read a Filter Transmission Chart guide to help you better understand the capabilities of any filters you may be interested in. With this article, you’ll be readily equipped with the knowledge needed to make a well informed, data-driven decision based on your specific needs.

    ​

    3 nm SII graph}

    ​

    chroma SII soul nebula

    3 nm SII Bandpass
    Sulfur is one of the many glowing gases within emission nebulae—with SII emitting red light at a wavelength of 672 nm. In order to produce stark contrast on this emission, Chroma Technology has developed this filter with a 99.19% transmittance at the 672 nm wavelength and features a super-narrow bandwidth of 3 nm. Light from the Moon or urban settings is of no concern, allowing you to capture narrowband data even during gibbous Moon phases or within the city. Compared to an 8 nm filter, this narrower 3 nm bandwidth blocks out a higher amount of undesirable wavelengths for a significant increase in SII definition. As a vital component of SHO imaging, combine the data captured through this Chroma 3 nm SII filter with OIII and H-alpha data to create vibrant Hubble Palette images rich in color!

    ZWO and QHY EFWs

    Effortless Integration
    Compatible with most filter wheels and filter drawers, seamlessly join this Chroma 3nm SII filter to almost any set up! A wide variety of user-supplied filter holders, such as the ZWO EFW 8-position Filter Wheel, ZWO EFW Mini Five-Position Filter Wheel, and the QHY CFW3 Small Color Filter Wheel are great choices to house this Chroma filter within. The 1.25” size is wonderful for use with sensors featuring a diagonal less than than 31 mm, with Micro 4/3 sensors and smaller yielding the best results. The male threads on this mounted filter feature a height of 1.75 mm, while the filter cell height excluding these threads is 5.25 mm. The total filter height is 7 mm.

    chroma SII close up

    Precision in Every Detail
    Understanding the ins and outs of filter development, Chroma Technology has crafted this SII filter with hard coatings built to last. They’re applied utilizing a technique called reactive magnetron sputtering and are extremely resilient to environmental stress. This means humidity and extreme temperature changes will not decrease the performance of this Chroma SII filter, as the spectral accuracy in the central wavelength (CWL) is effectively upheld. To eliminate the need for lamination and in-turn improve the filter’s overall performance and durability, Chroma Technology develops their astronomy filters with single substrates of the highest quality glass. Both sides of this glass are fully coated, with the rear side featuring anti-reflective coatings. This prevents image distortions as well as back reflections within the captured frames.

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