High-quality printing requires 3 to 4 times bigger image resolution as it appears on the monitor. Thus, "good looking" images on the monitor may be unacceptable in printing. For high-quality images in our book, we need to know the size of them in pixels.

• The image size can be found in the image properties in Windows Explorer, e.g. 1024x768, 2500x1600, etc..
• In Google Image Search, that number is shown next to the picture if you put your mouse over it.
• As a rule, approx. 10 cm wide, high-quality printing can be produced from a 1000 pixel image. Thus, a high-quality 20x16 cm print can be made from a 2500x1600 pixel image.
• However, not even a passport photo can be taken from a 300x200 pixel image.

In Word, images “tend to jump” to another page if e.g. we try to change their size. This is an annoying problem for longer material and there is no good solution to it.

Word does not handle transparent images well (such as png). It is more fortunate to use JPG images.

Word supports the RGB color mode and not the CMYK color mode used by printing offices. Thus, in many cases, the colors of created PDF files need to be converted, and conversion can cause unexpected surprises.

• Many RGB colors are not part of the CMYK colors. Thus eg. the neon green color that can be perfectly printed by a dirt-cheap inkjet printer at home may be colorless by a ten million digital or a hundred million offset pressing machine.
• We have already seen where the black color channel was missing when it was decomposed into colors in a PDF made from Word. Without black, it is quite difficult to print e.g. the shady parts in an image.

Fortunately, these conversion problems are most common in offset printing. Digital printing machines making fewer copies are more tolerant for the RGB color mode, with much less error.