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Antlia Imaging Herschel Wedge with CaK 3nm Filter - 1.25"

Antlia Imaging Herschel Wedge with CaK 3nm Filter - 1.25"

by Antlia
SKU ANT-CAK-WEDGE
CA$481.00 - CA$481.00
CA$481.00
CA$481.00 - CA$481.00
CA$481.00
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  • For high-resolution solar imaging with refractors only: aperture no larger than 120mm or f/5.5 or longer
  • 35mm Herschel prism: a design well known for sharper, higher-contrast images
  • Integrated 3nm narrow bandpass CaK filter centered at 393.3nm
  • Extra thick polycrystalline ceramic diffuser plate, cooling vents and rear heat-sink fins
  • Built-in brightness control ring with adjustable aperture blades
  • Includes a sun centering finder
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Antlia Imaging Herschel Wedge with CaK 3nm Filter - 1.25"

    The Antlia Imaging Herschel Wedge replaces the standard prism diagonal at the rear of a refractor telescope to enable imaging of solar granulation and sunspots. It combines a 35mm prism with a 3nm Calcium II K-Line (CaK) filter centered on 393.3nm, mounted in a standard 1.25" holder and screwed into the eyepiece holder base. It is for refractors only, with an aperture no larger than 120mm or a focal ratio of f/5.5 or longer. With its ceramic diffuser, brightness control ring and sun centering finder, the system provides for the safe management of harmful light intensity and heat when imaging the Sun.

    CaK Imaging at 393.3nm: A 3nm Bandpass for High-Contrast Granulation

    This wedge is built around a narrow 3nm bandpass CaK filter, precisely centered on the 393.3nm wavelength. Antlia designed it to maximize contrast for high-resolution imaging of sunspots, solar surface granulation and other features that are prominent in CaK light. Because of the eye's low sensitivity and poor resolving ability at 393nm, solar features are almost invisible to human vision, so this is an imaging-only system.

    The Herschel Wedge design is well known to give sharper, higher-contrast images, and the optical components are multi-coated with anti-reflection coatings to minimize internal reflections and contrast-reducing stray light. The prism and filter are made of heat resistant double-polished substrate, and the high blocking specification, OD5 (0.001%) between 200-1200nm and OD3 (0.1%) between 1200-1500nm, rejects solar heat ingress.

    Heat Management: Ceramic Diffuser, Cooling Vents and Heat-Sink Fins

    Managing the sun's focused energy is critical in any solar instrument. The Antlia wedge directs energy into an extra thick polycrystalline ceramic diffuser plate at the rear of the wedge. Cooling vents above the ceramic plate help cool the system, and excess heat is transferred to the rear fins, which act as a heat sink.

    The wedge must only be used with refractor telescopes, to avoid damage to the unit, and the refractor aperture must be no larger than 120mm or the focal ratio f/5.5 or longer. Within these limits, the heat management system keeps the instrument at safe operating temperatures.

    Refractor-Only Imaging System with Integrated Finder and Brightness Control

    The Antlia CaK wedge is housed in a sturdy, CNC machined body. An included sun centering finder helps you point the telescope at the Sun. A control ring with aperture blades, similar to that used in camera lenses, lets you conveniently increase or decrease the image brightness.

    This system is strictly for use with refractor telescopes: it must only be used with refractors to avoid damage to the unit. The wedge replaces the standard prism diagonal at the rear of the refractor. Never use the solar wedge without the supplied narrowband filter, otherwise irreparable eye damage can result.

  • Why is the Antlia Herschel Wedge for imaging only and not visual observation?

    The integrated filter is a narrow 3nm CaK (Calcium-K) filter centered at 393.3nm. Because of the eye's low sensitivity and poor resolving ability at this wavelength, solar features are almost invisible to human vision. The wedge is designed for imaging with cameras that have spectral responses well beyond human vision. Never look into the Sun with the K-Line filter alone: although you do not perceive it, a lot of harmful UV radiation enters your eye.

    What solar features can I image with the Antlia CaK 3nm wedge?

    Antlia designed this wedge for high-resolution imaging of granulation, sunspots and other features prominent in CaK light, such as:

    • Solar Granulation: The "boiling" convective cells covering the sun's surface.
    • Sunspots: Dark, cooler regions on the solar surface.
    • Faculae: Bright regions, most prominent near the solar limb.

    It is not intended for solar prominence imaging.

    Can I use the Antlia Imaging Herschel Wedge with my 8" SCT?

    No. The Herschel Wedge must only be used with refractor telescopes, to avoid damage to the unit, and the refractor aperture must be no larger than 120mm or the focal ratio f/5.5 or longer.

    How does the brightness control on the Antlia Herschel Wedge work?

    The wedge features a manual control ring with internal aperture blades, similar to a camera lens iris. Adjusting the ring opens or closes the blades to conveniently increase or decrease the image brightness at the camera.

    What is the purpose of the ceramic diffuser plate on the Antlia wedge?

    The wedge transmits a greatly reduced, safe amount of light to your camera and directs the remaining energy into the extra thick polycrystalline ceramic diffuser plate at the rear of the wedge. Cooling vents above the plate and the rear heat-sink fins dissipate the heat, keeping the instrument at safe operating temperatures.

    How do I safely align my 100mm f/7 refractor on the sun with the Antlia CaK wedge?

    A 100mm refractor is within the aperture limit. The wedge includes a sun centering finder for pointing the telescope at the Sun, so you never need to look at the Sun through the telescope. Follow the instructions supplied with the finder to fit and use it, and never look directly at the Sun.

  • Product Type Imaging solar wedge (Herschel wedge design) with built-in CaK filter
    Prism 35mm Herschel prism, AR coated
    Built-in Filter CaK (Calcium II K-Line) 3nm narrow bandpass, centered on 393.3nm
    Filter Mounting Standard 1.25" holder, screwed into eyepiece holder base
    Filter Blocking OD5 (0.001%) between 200-1200nm; OD3 (0.1%) between 1200-1500nm
    Substrate Heat resistant, double-polished (prism and CaK filter)
    Heat Management Extra thick polycrystalline ceramic diffuser plate, cooling vents, rear heat-sink fins
    Brightness Control Control ring with aperture blades
    Solar Finder Included (sun centering finder)
    Construction CNC machined; optical components multi-coated with anti-reflection coatings
    Telescope Compatibility Refractors ONLY
    Telescope Limit Refractor aperture no larger than 120mm, or focal ratio of f/5.5 or longer
    Intended Use Imaging ONLY (granulation, sunspots); not for visual observation or prominence imaging
    Safety Notice Never use the wedge without the supplied narrowband filter; never look into the Sun with the K-Line filter alone
    Warranty 1 year
    Warranty Condition Disassembly of the prism is prohibited and voids the warranty
    Barrel Size 1.25"
    Telescope-Side Connection 1.25" barrel

    • Imaging Herschel Wedge

      with 35mm prism, ceramic heat diffuser and brightness control ring

    • CaK 3nm 393.3nm Solar Filter

      1.25" (screwed into the eyepiece holder base)

    • Solar Finder

      × 1

  • Antlia 1-Year Manufacturer Warranty. Disassembly of the prism is prohibited and voids the warranty; repairs, returns and exchanges are not accepted once it has been disassembled.