More than 40 years ago, the Daystar founder Del Woods began manufacturing narrow band H-alpha filters for solar observation. These filters are used by both amateurs and universities alike, and have even flown into space aboard the space shuttle.
In 2014, DayStar introduced a new H-alpha filter under the trading name QUARK. The QUARK revolutionised solar observation because it offers very high contrast at a reasonable price, and can be used with existing refractors.
The QUARK module is now also available for other wavelengths, and DayStar also offers it pre-installed into refractors.