The Baader AstroSolar® ClearWhite Safety Film OD 5.1 is a high-quality, double-sided metallised solar filter film for direct observation of the Sun and for constructing front-mounted lens filters for telescopes, binoculars, spotting scopes and camera lenses.
The film has an optical density of OD 5.1 and reduces the intensity of sunlight by approximately 99.9992 per cent, or by a factor of approximately 125,000. It meets the relevant transmittance requirements of EN ISO 12312-2:2015 for filters intended for direct observation of the Sun.
Compared to the AstroSolar® Safety film OD 5.0, the new ClearWhite version offers an even clearer, whiter image of the Sun and a slightly higher optical density. Sunspots, granulation and fine structures of the photosphere are visible in sharp, high-contrast detail when viewed through suitable optics.
Clear, white image of the Sun with high optical quality
AstroSolar® ClearWhite Safety Film OD 5.1 has been developed to provide a particularly neutral, clear-white image of the Sun. Undesirable bluish or orange colour casts, such as those that can occur with simpler solar filters, are largely avoided.
The film is manufactured from a special film free of streaks and bubbles and, at a thickness of just 0.012 mm, achieves an optical quality comparable to that of high-quality plane-parallel glass filters. The material is not ordinary ‘Mylar’ and has been developed for particularly high uniformity and optical purity.
The double-sided coating ensures a particularly uniform filtering effect and reduces the influence of isolated microscopic irregularities in the metallisation. A single layer of AstroSolar® ClearWhite Safety Film OD 5.1 is sufficient to create a safe solar filter with high sharpness.
When used correctly, AstroSolar® ClearWhite Safety Film OD 5.1 can be used for direct solar observation with the naked eye. This is provided that the film is undamaged and is used in a suitable, light-tight and securely fastened mounting.
For telescopes, binoculars, spotting scopes and camera lenses, the film must only be used as a front-mounted lens filter. The filter must be positioned in front of the optical system’s entrance aperture, securely cover the entire aperture and be secured against slipping, coming loose or being blown off by the wind.
Visual and photographic use
The AstroSolar© ClearWhite Safety Film OD 5.1 is equally suitable for photography and visual observation. Given the aperture ratio of standard telescopes and camera lenses, exposure times are short enough to capture a sharp image of the Sun in single shots or to practise ‘lucky imaging’ – ideal for observation and photography of the normal Sun as well as the partial phases of solar eclipses. You also need not worry about looking through the camera viewfinder; this can be done safely.
