The Tiffen #2 viewing filter is designed for films up to 100 ISO. Balancing lighting by eye is a matter of experience. Decisions can be made easier by using contrast viewing filters. These are designed to handicap the eye, with its much wider range of apparent densities, to resemble the range of different types of film.nnnFeatures:nn- Use contrast viewers to judge the relative densities of highlights and shadowsn- There are viewers for black and white films, as well as different density viewers for colour filmsn- A darker viewer is used for slower speed films, where you would tend to use brighter lighting; a faster film, which can be used in darker environments, would require a lighter viewernnTiffen viewing filtersnn- #1 is for black and white imagingn- Viewer #2 is for films up to 100 ISOn- #3 is for faster films; they can also be used for video, with #3 being better suited to lower light levelsn- The green #4 viewer is for process photographyn- The blue #5 is for blue screen work, as well as for adjusting colour video monitorsnnSpecifications:nn- Type: Viewing filtern- Size: Not applicablen- Grade: 2n- Filter factor: Not specified by manufacturern- Multi-coated: Not applicablen- Rotating: Not applicablen- Effect: Judges the relative densities of highlights and shadowsn- Application: For judging contrast in black and white photography with films of sensitivity greater than 100 ISOn- Colour temperature: Not applicablen- Construction: Glassn- Front filter thread size: Not applicablen- Front lens cap size: Not applicable