Computer-to-film

Computer to film (CTF) is a print workflow involving printing from a computer straight to film. After that, the film image is burned onto a lithographic plate, using a plate burner. The plate is then put on an offset printing press to make a product, usually up to about 100,000 copies, after which a new plate must be made. The process requires a clean environment, skilled workers, and a well-thought-out proofing system in order to maximize quality.

With advances in the technology of heat stabilization of polyester film, new-generation laser printer films provide excellent image registration and sharpness for multi-colour jobs. For multi-coloured printing, the image is broken up into four images for CMYK printing, using special software. Each of the four images is printed on a separate laser film which is then used to expose pre-sensitized plates using ultraviolet (UV) light.

CTF is being replaced by the more advanced computer to plate (CTP) technology. Compared to CTP, the cost of maintaining and running a CTF system is much cheaper, even though it requires an additional step in the plate-making process.

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Wikipedia