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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Explore Scientific Nebula Filter H-Alpha 2-inch 7nm
Explore Scientific Nebula Filter H-Alpha 2-inch 7nm
Explore Scientific Nebula Filter H-Alpha 2-inch 7nm
Explore Scientific Nebula Filter H-Alpha 2-inch 7nm

Explore Scientific Nebula Filter H-Alpha 2-inch 7nm

by Explore Scientific
SKU ES-310140
$299.99 - $299.99
$299.99
$299.99 - $299.99
$299.99
Price Match Policy!
  • 7nm H-Alpha Bandpass
  • 2-inch Filter Format
  • Isolates Hydrogen Emission Nebulae
  • Blocks Urban Light Pollution
  • Includes Individual Test Report
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Explore Scientific Nebula Filter H-Alpha 2-inch 7nm

    The Explore Scientific H-Alpha 2-inch Nebula Filter isolates the specific wavelength of hydrogen emission nebulae within a tight 7nm bandpass, making it an essential tool for urban astrophotography. By aggressively rejecting light pollution from mercury and sodium vapor lamps, this 2-inch filter reveals faint, extended structures that are otherwise completely lost against a brightened sky.

    A 7nm Bandpass for Maximum Nebula Contrast

    This filter's narrow 7nm window is engineered to transmit only the red light associated with ionized hydrogen, the primary element in most emission nebulae. By blocking all other wavelengths, the filter dramatically darkens the sky background, causing the faint signal from your target to stand out with striking contrast. Photos taken with the filter reveal details in objects like the North American Nebula (NGC 7000) that appear completely empty without it.

    Urban Astrophotography with a 2-inch H-Alpha Filter

    Light pollution is the single greatest challenge for deep-sky imagers. The Explore Scientific 7nm H-Alpha filter is designed specifically to solve this problem, enabling high-quality astrophotography from city and suburban locations. It effectively nullifies the glow from common streetlights, transforming a washed-out sky into a dark canvas and making surprisingly deep images possible despite local light pollution.

    Individually Tested for Guaranteed 7nm Performance

    To ensure you receive a high-quality optical component, every Explore Scientific nebula filter is supplied with an individual test report. This certification verifies that your specific filter meets its stated transmission and bandpass specifications. This commitment to quality control guarantees that you are capturing the maximum amount of signal from your target while effectively blocking unwanted light.

    7nm H-Alpha vs. Broadband LPR Filters: Choosing the Right Tool

    While both filter types combat light pollution, they serve different purposes. A broadband Light Pollution Reduction (LPR) filter is a general-purpose tool that passes a wide range of wavelengths, making it suitable for galaxies and star clusters. This 7nm H-Alpha filter is a specialist's instrument with a much narrower bandpass.

    • H-Alpha 7nm Filter: Exclusively for emission nebulae. It provides the highest possible contrast but will block almost all light from broadband targets like the Andromeda Galaxy (M31) or reflection nebulae.
    • Broadband LPR Filter: A jack-of-all-trades filter that provides a modest contrast boost on all deep-sky objects but cannot match the dramatic effect of a narrowband filter on emission nebulae.

  • What is the primary use for the Explore Scientific 7nm H-Alpha filter?

    This filter is designed exclusively for astrophotography of emission nebulae. Its narrow 7nm bandpass isolates the hydrogen-alpha wavelength, dramatically increasing contrast and revealing faint details, especially from light-polluted locations.

    Can I use the Explore Scientific 7nm H-Alpha filter for visual observing?

    No, this filter is not recommended for visual use. The 7nm bandpass is so restrictive that it blocks too much light for the human eye to perceive a useful image. It is specifically engineered for long-exposure imaging with a digital camera.

    How does the 7nm bandpass on this H-Alpha filter help with light pollution?

    Light pollution from sources like mercury and sodium vapor streetlights is "broadband," meaning it emits light across many colors. The 7nm H-Alpha filter blocks all of these colors except for a very narrow 7nm-wide slice of red light where emission nebulae shine. This effectively removes the skyglow from your images, resulting in a much darker background and higher contrast on your target.

    Will the Explore Scientific 2-inch H-Alpha filter improve my images of the Orion Nebula (M42) from my backyard?

    Yes, absolutely. The Orion Nebula (M42) is a massive hydrogen-alpha region. Using this 7nm filter will cut through local light pollution to reveal the faint outer loops and intricate details in the nebula's core that are typically washed out in unfiltered images from a suburban or urban setting.

    I have an 8" SCT with a 2-inch focuser. Is this Explore Scientific H-Alpha filter the right size?

    Yes, the 2-inch format is ideal for an 8" SCT or any telescope equipped with a 2-inch focuser and accessories. It will thread directly into your 2-inch diagonal, filter wheel, or camera nosepiece, ensuring it won't cause any vignetting, even with larger camera sensors.

    What does the included individual test report for the Explore Scientific H-Alpha filter tell me?

    The test report is your assurance of optical quality. It provides a graph showing the exact transmission curve for your specific filter, verifying that it meets the 7nm bandpass specification and is centered on the correct H-Alpha wavelength. This guarantees you are getting the performance needed for high-contrast imaging.

  • Filter Type H-Alpha Narrowband
    Bandpass 7nm
    Size 2-inch
    Primary Use Astrophotography

    • Nebula Filter H-Alpha 2-inch 7nm

      × 1

    • Individual Test Report

      × 1

    • Protective Case

      × 1

  • No manual or software is available for this product.

  • Explore Scientific Warranty