The following factors should be considered when choosing the proper film:

The color of the original to be copied

The contrast of the original

The contrast of the film

The type of product to be produced, that is, black-and-white or color print, duplicate negative, color or black-and-white transparency, and so on

Color quality of the light source

Types of film available

Color sensitivity of the film

Filters available

Black-and-White Line Originals

A black-and-white line original has no middle or intermediate tones between the lines and background. Therefore, the best film for copying black-and-white line originals is one with extreme contrast, such as Kodak Kodalith film. These films produce high contrast and extremely high density with an absence of fog, which ensures clear lines on a dense background.

Kodalith type of films have a very limited exposure latitude, and therefore, must be given very accurate exposure. Underexposure produces low-contrast negatives that result in prints having a muddy gray background instead of a clear, crisp, white background. Overexposure causes weak or very fine lines to fill in and results in a less than perfect transparency of the lines on the negative.

Typewritten material should be included in this type of original. When an original is typed or printed on thin white paper and on one side only, you should place another sheet of white paper behind the original to copy it. This increases the reflective ability of the original and increases contrast. When the original is printed or typed on both sides of thin white paper, place black paper behind the original to help prevent the printing or type on the reverse side of the original from showing through.

Colored Line Originals

In copying colored line originals to a black-and-white reproduction, you must maintain the high contrast between the lines and the background. This is best achieved by using a high-contrast panchromatic film, such as Kodak Contrast Process Pan film and a filter. When the lines or subject is to be rendered light against a dark background, the filter should transmit the color of the subject and absorb the color of the background. When the subject is to be rendered dark against a light background, the filter should absorb the color of the subject and pass the color of the background.

For example, a blueprint has white lines on a blue background. Copying the blueprint with Kodalith Pan film without a filter cannot produce maximum contrast because the film is highly sensitive to blue light and thus records the image of the blue background as a midtone of gray while recording the white line image as a dense highlight. When a red filter is used, the white lines still record as a dense highlight on the negative, but now the

blue background records as a shadow area because the red filter absorbs the blue light reflected from the blue background. Thus the background reproduces darker when a red filter is used.

Black-and-White Continuous-Tone Originals

To reproduce the tone gradation of a continuous-tone original, you must use a long-scale film. As discussed previously, a commercial type of film, such as Kodak Commercial film, is recommended.

The common fault in continuous-tone original copying is underexposure and overdevelopment. Full exposure with restrained development is the best rule for this type of work

Although appearing as line originals, handwritten material, pencil drawings, and so forth, are actually continuous-tone originals because of the midtones they contain. These should be copied as continuous-tone originals. Films, such as Kodak Professional Copy film or Kodak Commercial film, are recommended.

Colored Originals

When a black-and-white reproduction of multicolored reflection originals, such as color photographs, oil paintings, and so forth, is to be made, it should be copied with a moderate contrast, panchromatic film capable of recording numerous shades of gray. Panchromatic, long-scale film is recommended for copying this type of color original.

Colored originals are almost limitless in their degree of difference because of all the possible colors and hues. Each different colored original should be copied on the basis of what is desired in the black-and-white reproduction.

Color Reproduction of Color Originals

Selecting a film for copying colored reflection originals to make color reproductions is a matter of what type of reproduction is needed-reflection or transparency. Films, such as Kodak Vericolor III Professional Film Type L and Type S and Vericolor Internegative Film, can be used to produce color reflection copies. Color transparency film must be used to produce color transparencies from reflection originals. Some films have a different recommended ISO rating when used with tungsten or daylight light sources. Be sure to consult the data sheet supplied with the film or the Photo-Lab Index to determine the proper ISO setting.

When you are copying a color print to a color negative, the best film to use is Kodak Internegative film. Because of the inherent high contrast of photographic papers, if not controlled, contrast is gained in each generation of a reproduction. Kodak Internegative film is designed to give greater contrast separation in the highlights without raising the overall subject contrast in the negative. To achieve proper color balance in the shadows, midtones, and highlights, you must perform tests to assure that proper exposure and color filtration is obtained. The Photo-Lab Index contains the procedures necessary to accomplish this testing.

Combined Black-and-White Line and Continuous-Tone Originals

When a black-and-white original contains both line and continuous-tone matter, the ideal copy method is to copy each type of matter with an appropriate film separately and then sandwich the two negatives together, or print the two negatives separately on the same piece of paper. The colored lines should be copied with an extremely high contrast film, such as Kodalith Pan, and the pastel-colored portions of the original should be copied with a moderate contrast film.

When copying the original with only one type of film, you loose quality in either the lines or the continuous tones. For best results, you should copy the combined line and continuous-tone original with a moderate contrast film, such as Kodak Professional Copy film or Kodak Commercial film.

Black-and-White Halftone Originals

A black-and-white halftone original consists of a pattern of black dots of various sizes that represent tones of gray. Examples of halftone originals are printed pictures in newspapers or magazines. Small dots with ample white space between them produce an illusion of a light tone or highlight. Large dots that are close together produce the illusion of dark tones or shadow areas. Because the dots are all the same tone (black), halftone originals can be copied as line originals. This type of original can also be copied as a continuous-tone original, depending on the use of the final product.

Reflection Originals Specifically Produced for Copying

When an original is to be used specifically for copying, you can take certain measures to ensure better reproduction results.

PHOTOGRAPHIC PRINTS. Black-and-white and color prints produced for copying should have normal density, color saturation, and a glossy surface. When a non-glossy surface is used, the texture of the surface may be apparent in the copy negative and reproductions.

TYPEWRITTEN MATERIAL. Typewritten material that is to be copied should be typed with a new typewriter ribbon. A carbon one time ribbon is best. To further increase contrast between the type and the paper background, you can place a sheet of carbon paper behind the typing paper. This causes the carbon to be transferred onto the back of the paper during typing.

When using a typewriter to produce copy that will be photographed for making 35mm slides, limit your typing to no more than 8 double-spaced lines with 43 elite or 36 pica characters to a line. When photographing typed copy, use a template as a guide for setting up your camera Allow about 1/8 inch of space outside the template lines in the camera viewfinder.