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We have a large job running on two different sheetfed presses at the same time. Both presses are running the same paper, ink, and fountain solution. On one press the fit is acceptable; on the other press the image is out of register by several rows of dot

Paper expansion or distortion is usually caused by excessive impression cylinder pressure and/or excessive fountain solution on the plate(s) transferring to the paper. Ink coverage, high tack, and the smoothness of the surface of the blanket can also contribute to paper distortion. Excessive fountain …

I have a four-color separation that appeared ok on the screen and in the proof, but a moir� appeared in the printed image. To our knowledge our screen angles and RIP settings are correct. Why is this happening?

I have seen this happen when the TVI (tonal value increase or dot gain) on the proof is low and/or very high on the litho press. In one example, the TVI was too high because the press operator had to make the magenta ink film very heavy (the magenta or yellow separations are too weak) to match the …