These filters, manufactured from the finest solid optical glass, are ground and polished to the most practical thinness. In addition, they are heat-treated to avoid any distortion or focal shift, and each filter is subject to strict tests in order to ensure a perfect even surface which is essential to a good filter.
This UV filter absorbs ultra-violet rays without increase of exposure, thereby preventing haziness and foggy effects in distant landscape. It creates clearness. Constant use of this filter is recommended for clearer pictures as well as a lens protector.