The Hoya PRO ND100000 filter is a specially designed for solar photography, both shooting the full sun and solar eclipses. This is a ultra dark filter with a filter factor of 100,000 meaning it only passes 1/100,000 of the light that enters the filter. That translates to a light reduction of just over 16.5 stops. This is necessary due to the sun’s intensity even during a solar eclipse.

The more than 16.5 stops of light reduction can also yield exposure times of several minutes during daytime where the sun is not actually in the photo. Hoya uses a precise metal vapor deposition process to create the ultra-dark ND effect while maintaining a very neutral color balance for faithful color reproduction at very long exposure times.

The PRO ND100000 is available in 58,67,77 and 82mm sizes only. If the size is not available to match a particular lens, purchase the next larger size and use an appropriate step-up ring.