Daystar QUARK photographic calcium H-Line sun filter

This accessory from the QUARK series allows you to observe the sun in the calcium H line. Like every QUARK filter, this one is simply plugged into the telescope's focuser.

Please note: The QUARK Calcium H-Line solar filter should only be used in conjunction with refractors (lens telescopes) up to a maximum of 150 millimeters. For an opening of 80 millimeters or more, a UV/IR block filter should be used, although it must still be transparent to the light from the calcium H line (see “Recommended accessories”). The refractor should not have any optical elements downstream of the front lens, since high temperatures occur near the focal point - nomen est omen - which damage these elements. So please do not use flatteners, Barlow lenses or anything similar.

The manufacturer DayStar recommends refractors with an aperture ratio of f/8 to f/15.

With a longer focal length, the image becomes darker but has greater contrast.

The two spectral lines calcium-K (CaK) and calcium-H (CaH) are just as important in scientific solar observation as the H-alpha line of hydrogen. The two calcium lines have wavelengths of less than 400 nanometers. The sensitivity of the human eye noticeably decreases with age. Filter manufacturers therefore concentrate on the shorter CaK wavelength and recommend purely photographic observation because the CCD chip is sensitive enough.

The calcium QUARK is designed for the CaH line. At 397 nanometers, this has a slightly longer wavelength than the CaK line (393nm). According to the manufacturer, this color is still visible to most people, so the calcium QUARK is also suitable for visual observation.

In calcium light, as in H-alpha light, you observe the chromosphere of the sun. The photo on the right gives an impression. Protuberances can also be seen in the light of the calcium ions. Due to their low brightness, they are primarily photographic.
Technical data:
Performance
Connection (telescopic side) 1.25"
Current consumption (mA) 1500
Power supply (volts) 5
Half width (angstrom) 5
Spectral line (angstrom) 3968.5
Connection (eyepiece side) 1.25"
Clear passage (mm) 21
equipment
Power supply yes
Generally
Quark series
Solar filter type
Line filter design
Areas of application
Can be used for photography, yes
 


♦ Daystar Quark calcium filter