Lunt Solar Systems Filters H-alpha LS50FHa/B1800d1 (12689)

The BF blocking filter is an essential component of a solar telescope, integrated within the deflection optics and eyepiece holder. Its main function is to reduce the brightness of the solar image, ensuring safe observation and protecting both the observer and the equipment. This filter must never be removed. For visual observation, a smaller blocking filter is usually sufficient, while a larger one is recommended for solar photography to ensure optimal image coverage.

The B1800 blocking filter is well-suited for visual solar observation and can also be used for solar photography with cameras that have small sensor chips or APS-C format sensors. For cameras with larger sensors, a telescope with a larger blocking filter is necessary to fully illuminate the sensor. For solar imaging, planetary cameras are generally recommended, as they work efficiently with this blocking filter.

The LS50 filter provides a bandpass of less than 0.70 Angstroms, delivering high-contrast views of both surface and edge details on the Sun. Adding an additional etalon system can further reduce the bandpass to around 0.50 Angstroms, depending on the telescope, allowing for even higher resolution in visual observation or imaging.

Specifications

Capacity

• Frame: Lens filter

• Free transmission: 50 mm

• Half-value width: Less than 0.75 Angstrom

• Connection to eyepiece: 1.25"

• Connector at camera end: T2

• Connection to telescope: 1.25"

• Additional connection: M90

Equipment

• Transport case: Yes

General

• Type: Solar filter

• Type of build: Line filter