Gosky 150mm Solar Filter for 150mm Aperture Sky-watcher Telescope - Baader Planetarium Solar Film 150mm Solar Filter for 150mm Aperture Sky-watcher Telescope. A must-have, white light filter for safely observing the sun and su nspots without damaging your eyes With this filter the Sun will be of a neutral, eye-pleasing white color. See sunspots, eclipses, and planetary transits of the Sun safely with your telescope and this filter Made with high-quality, streak-free and blister-free Baader Astro Solar Safety Film CAUTION: Never look at the Sun, either directly or through a telescope, without a professionally made protective solar filter installed that completely covers the front of the instrument, or permanent eye damage could result. Optical density: 5.0 Aperture of the telescope