Requirements for the resolution of the
original files in book printing
The definition of the original image is the
clarity of the painting surface, the ideal printing of the original particle
fine, especially when copying, the higher the magnification, the finer the
original particle, the better the reproduction effect. In the pre-press process
of book printing, the subtle level
of the image can be adjusted by the power extension or DTP system to improve
the resolution of the image. However, if the resolution cof the original
manuscript itself is not high, the ideal effect can not be achieved only by
relying on the software to adjust. For digital image, its definition depends on
the size of the image resolution, the larger the image resolution is, the
higher the resolution is.
What is the hierarchy of printed files
The image hierarchy refers to the density
grading from the brightest to the darkest on the image. The ideal original
should be highlights, clear middle and dark tones, rich and complete steps.The
loss of the original layer mainly refers to the density of the darkest part of
the image, and the loss of the middle and dark layer, which leads to the
contrast of the whole picture is too large
How to judge and correct the original files
color bias in book printing
In the production process of the original,
due to the influence of illumination, photographic equipment, developing
conditions and other factors, the original color offset is inevitable, common
overall color offset, dark color offset, light color offset and cross color
offset.
We can judge and correct the color bias of
the original through the extension, Mac or PC scanning software or image
processing software, that is, according to the neutral gray in the image to
judge whether the original color bias.If the values of the three components of
RGB in the neutral gray area are equal, or in LAB color mode, the values of A
and B are equal to 0, it indicates that the original draft has no color bias. Once
found color bias, correction must be considered as a whole, can not see a color
immediately deal with a color, otherwise it will cause other color bias.
