Antlia Herschel Wedge with 3 nm Calcium Filter

Codice articolo: AHEKAC

The solar prism allows photography of the sun in visible light and in calcium light through refractor telescopes.

♦ Large dimensioned 35 mm prisms

♦ Adjustment of image brightness via a variable ring diaphragm in front of the prism

♦ Effective heat dissipation into an extra thick ceramic diffuser plate and cooling holes above the plate for good heat regulation

♦ 1.25" and T2 mount on camera side and 1.25" mount on telescope side

♦ 3 nm calcium filter included for high contrast photography for the solar surface

♦ For visual observation an ND3.0 filter is still necessary (optional accessory)

♦ Delivery in robust transport box

Antlia 1.25" solar prism with complete equipment for photographing the sun in calcium light

The solar prism is suitable for refractor telescopes without built-in field flattener and is used instead of the zenith mirror. About 96% of the solar energy is dissipated by the Herschel-type prism, the remaining 4 percent are available for photography. The images are sharper and richer in contrast than with simple objective lens solar filters. In addition, the image brightness can be continuously adjusted by means of an adjustment ring on the telescope-side opening. The Herschel prism is CNC-machined and has anti-reflective coatings to minimize contrast-reducing stray light.

The calcium filter with 3 nm bandwidth:

Included is a narrow band calcium (CAK II) filter. This filter allows solar photography in the calcium line around 393.3 nm. The mounted 1.25" filter is installed in the eyepiece holder and can be easily removed and replaced by other filters. Sunspots are imaged in the calcium region, similar to white light. The flares, solar granulation, flares and even bright prominences in the edge region of the "solar disk" become visible to the photographer.

The visual observation of the sun with the Herschel prism:

The prism with the CaK-II filter is not suitable for visually observing the sun. If you replace the calcium filter with an optional ND3.0 filter, you can also observe with the prism. The continuously adjustable ring diaphragm allows mechanical adjustment of the brightness.

Solar observation and photography with other telescopes

Basically, we recommend only refractors without built-in field flattening for solar observation. The heat of the sun would heat up a secondary mirror or corrector lenses too much. Damage would be very likely.

More info about the Antlia Herschel prism:

♦ The heat radiation is diverted into an extra thick polycrystalline ceramic diffuser plate. This prevents concentrated radiation. In addition, cooling vents above the ceramic plate facilitate efficient cooling of the system.

♦ The 1.25" receptacle with the T2 connection allows the connection of cameras and eyepieces to the solar prism. On the bottom side, the barrel offers an internal thread for mounted 1.25" filters, in which the 3 nm CaK II filter is screwed in.

♦ The 35 mm prism is coated with an anti-reflective (AR) layer to reduce stray light.