Filters Sun iris screen, variable opening 10 - 113mm

Continuously adjustable iris diaphragm (externally heat-reflecting white anodised diaphragms, internally anti-reflective black diaphragms) from 13 to 113 millimetres for attachment in front of D-ERF filters from Baader. For optimum adjustment of a telescope aperture during observation with an H-alpha surface filter from SolarSpectrum (also suitable for other makes).

The aperture has four M3 internal threads on the telescope side on a hole circle radius of 60 mm for attachment to a DIY mount.