Increase or reduce size of photographic dots by chemical or photomechanical methods to make color corrections on halftone negatives or positives to be used in preparation of lithographic printing plates.

Places masks over separation negatives or positives and exposes film for specified time, using contact frame and automatic film processor to reduce size of photographic dots to increase or reduce color. Prepares photographic masks to protect areas of film not needing correction, using contact frame and automatic film processor or by manually cutting masking material, to correct color by photomechanical method. Compares proof print of color separation negative or positive with customer's original copy and standard color chart to determine accuracy of reproduction. Examines film on light table to determine specified color and color balance, using magnifying glass or densitometer. Identifies and marks color discrepancies on print and film. Applies opaque to defective areas of film to block out blemishes and pinholes. Determines extent of correction and exposure length needed based on experience or predetermined exposure and color charts. Prepares dyes and other chemical solutions according to standard and applies solution to inaccurately colored areas of film to correct color by chemical method. Blocks out or modifies color shades of film, using template, brushes, and opaque.

Chemistry -- Knowledge of the chemical composition, structure, and properties of substances and of the chemical processes and transformations that they undergo. This includes uses of chemicals and their interactions, danger signs, production techniques, and disposal methods. Fine Arts -- Knowledge of the theory and techniques required to compose, produce, and perform works of music, dance, visual arts, drama, and sculpture.

Operation and Control -- Controlling operations of equipment or systems .

Visual Color Discrimination -- The ability to match or detect differences between colors, including shades of color and brightness. Near Vision -- The ability to see details at close range (within a few feet of the observer). Visualization -- The ability to imagine how something will look after it is moved around or when its parts are moved or rearranged. Information Ordering -- The ability to arrange things or actions in a certain order or pattern according to a specific rule or set of rules (e.g., patterns of numbers, letters, words, pictures, mathematical operations).

Controlling Machines and Processes -- Using either control mechanisms or direct physical activity to operate machines or processes (not including computers or vehicles). Monitor Processes, Materials, or Surroundings -- Monitoring and reviewing information from materials, events, or the environment, to detect or assess problems. Handling and Moving Objects -- Using hands and arms in handling, installing, positioning, and moving materials, and manipulating things. Getting Information -- Observing, receiving, and otherwise obtaining information from all relevant sources.