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	Tone Reproduction The theory behind tone reproduction is to successfully manage the placement of halftone dots (highlight, midtone, and shadow) to maximize contrast and detail for the interest area of an image. To optimize reproduction, every image should be handled on an individual basis for proper tonal distribution. Non-detail White Dropout Remove all printing dots from non-detail whites to maximize the entire available print range between paper brightness and total ink saturation. A common example of a non-detail white is the reflection from a shiny surface (reflections on chrome, jewelry, and electronics). Adjusting Midtone Placement Adjusting the midtone is crucial to optimizing the area of interest in an original. Lighting conditions and subject content dictate the need for modified midtone placement. Many quality failures occur when subject midtones are not properly adjusted in the scanning process. This can result in images printing too dark, even though specifications are adhered to. Midtone placement is dependent on each unique image and subject content. Midtones should be lightened (less printing weight) for dark images. Shadow/Range Restoration A common error made in tone reproduction is to make necessary midtone adjustments without restoring the shadow range (darkest setting). Because the shadow is pulled open by powerful midtone manipulations (opening up for detail) it is important to restore the shadow to its maximum density. With high-key originals, slightly more weight than specified can be given to non-detail shadows enhance print contrast. Enhancing Sharpness Aside from tone reproduction, a final strategy for producing quality halftones is electronic digital sharpness. In most originals, it may be beneficial to apply additional electronic digital sharpness. This works to improve the perception of detail and clarity in the image. The amount of sharpness employed depends on the smoothness of photo emulsion and enlargement size. Noticeable white or black image outlines can result if an excessive amount of digital sharpness is applied. Screen Ruling Newsday is output at 100 line screen. However, a finer screen ruling, up to 120 lpi, may be considered to improve image quality. Because a higher screen ruling can lead to plugging in the shadow areas, it is important that the midtones and three-quarter tones be opened an additional 5-15% to allow for dot gain. The shadow should then be restored to normal specification for maximum contrast. Dot Gain Compensation Dot Gain can be described as the growth in size of a halftone dot through the successive stages of the printing process. The value measured in this assessment is "total dot gain" which includes both mechanical and optical dot gain. It is a measure of the total dot growth when producing negatives, plates and the printed sheet. Dot gain values are typically reported from the midtone portion of the printed material (50%). This measurement is a direct increase in the percent dot area. Therefore, a 50% film dot that produces an 85% printed dot, has a 35% total dot gain.

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