This tool facilitates the determination of the appropriate neutral density filter strength required for a given photographic or videographic scenario. It allows users to input the desired final aperture and shutter speed, along with the metered exposure without a filter, to compute the necessary light reduction. For instance, a user may input an unfiltered exposure of 1/250th of a second at f/8, with a desired final exposure of 1/30th of a second at f/2.8; the software then calculates the required filter density to achieve this.
The utility of such a device lies in its ability to streamline the creative process. Instead of relying on trial and error, photographers and videographers can quickly determine the optimal filter strength to achieve specific effects, such as motion blur in daylight or shallow depth of field under bright conditions. Its development has enabled greater precision and repeatability in image and video capture, saving time and resources. Historically, these calculations were performed manually, which was time-consuming and prone to error.