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Antlia Imaging Herschel Wedge with 35mm Prism and 1.25'' Cak 3nm Solar Filter

The Antlia Solar Wedge (Herschel Wedge design) replaces the standard prism diagonal at the rear of refractor telescopes to enable imaging of solar granulation and sunspots. The Herschel Wedge design is well known to give sharper, higher-contrast images. The Antlia Solar Wedge design transmits a greatly reduced, safe amount of light to your imaging camera. The image brightness can be conveniently increased or decreased using a control ring with aperture blades, similar to that used in camera lenses.

Our Herschel Wedge is produced using CNC machining and the optical components are multi-coated with anti-reflection coatings to minimize both internal reflections and contrast reducing stray light. The solar wedge incorporates an Antlia 3nm narrow bandpass filter at the Calcium II K-Line centered on 393.3nm and mounted in a standard 1.25’’ holder.

Unlike some other solar wedge designs which may get too hot, the Antlia Imaging Solar Wedge directs energy into an extra thick Polycrystalline Ceramic diffuser plate at the rear of the Wedge. In addition, cooling vents above the ceramic plate facilitate efficient cooling of the system.

The Antlia Cak 3nm solar prism system provides for the safe management of harmful light intensity and heat when imaging the sun. The system is comprised of a prism, Cak lens filter, sun centering finder and a heat dissipation system. The sun’s light passes through the right-angle prism and excess heat is transferred to the rear fins that act as a heat sink for cooling the instrument. This heat management system effectively keeps the the instrument at safe operating temperatures.

Application and Performance:

Type of build: Herschel 35mm prism

Integrated ceramic heat dispersion diffuser

Sharp CaK 3nm 393.3nm solar filter screwed into eyepiece holder base

High-resolution imaging of granulation, sunspots, and other features

Includes a brightness control, a solar finder and effective heat dissipation system

Anti Reflection (AR) coated prism and solar filter

High blocking specification to reject solar heat ingress

Sturdy CNC machined construction

CaK 3nm 393.3nm Filter Specifications

The Antlia Solar Wedge prism and internal CaK solar filter are made of heat resistant double-polished substrate. Antlia CaK 393.3nm solar filter uses the most advanced multicoatings to produce a sharp 3nm narrow bandpass, designed to maximize contrast for high-resolution imaging of sun spots, solar surface granulation and other features that are prominent in CaK light.

A high blocking specification of OD5 (0.001%) between 200-1200nm wavelengths and OD3 (0.1%) between 1200-1500nm wavelengths delivers superb resolution for imaging with the Antlia Cak 3nm solar filter.   It should be noted that the bandpass for Cak (393nm) makes solar features almost invisible to human vision because of the eye's low sensitivity and poor resolving ability at the CaK frequency. Hence, the Antlia Solar Wedge with CaK filter is not recommended for visual observation. It 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 don’t perceive it, there is a lot of harmful UV radiation entering your eye.

Please note:

The Antlia Herschel Wedge is intended for imaging ONLY. It is not suitable for visual observation.

It is not intended for solar prominence imaging and visual.

Must only be used with refractor telescopes to avoid damage to the unit.

Refractor aperture must be no larger than 120mm or, focal ratio of F5.5 or longer.

Never use the Solar wedge without the supplied narrowband filter. Otherwise irreparable eye damage can result.

Disassembly of prism is prohibited and voids warranty. Any repair/returns/exchange for this item is not accepted once it has been disassembled.

Warranty guarantee: 1 year