Best resolution for printing high resolution
Best resolution for printing high resolution books on press
Best resolution for printing high resolution books on press; get it right! There are a couple of rules to follow for the optimum resolution necessary to print images without them looking pixilated in print. Read below about size and resolution.
SIZE
Always use photographs or images at the dimensions they will be when printing, or larger. Keep in mind the dimensions of the image when enlarging or reducing, and when placing in the document. Save as TIFs or JPGs.
RESOLUTION
The resolution must be 300 ppi or larger. What matters is the effective resolution. To view in InDesign, go to Links. Highlight an image. In the panel below the links, see the Effective PPI as well as the Actual PPI.
An image with an Actual PPI of only 72 for example may print at an acceptable effective resolution if the dimensions are quite large. That is because the image can be reduced, so that the Effective PPI increases.
Simply put, reducing an image with a low Actual PPI means that you are increasing the Effective PPI.
BEWARE OF “REZING UP”
Do not increase resolution artificially, even if you see that you are allowed to do in Photoshop. This is called rezing up.
There is no substitution for the original digital or scanned image. If the image is rezed up, the printed image will be pixilated, even if it looks fine on your monitor. That is because images can be viewed on monitors at only 72 ppi or 92 ppi instead of the 300 ppi required for print.
The solution is to recreate the image, rescan the original image, or buy a larger image.
DESTINATION SPACE
Check with your printer. Star Print Brokers uses U.S. Sheetfed Coated v2 when printing on coated stock. In Photoshop, go to File > Convert to Profile. Select Profile: U.S. Sheetfed Coated v2.
Creating new images
When creating new images in Photoshop, make sure they will print well on press. If you simply need to convert existing images, skip this section, and go on to “Converting existing images from RGB to CMYK.”
Open Photoshop and then open a new document. Go to File > New . . . See the Preset Details on the right side of the open window as replicated in the illustration above. Save as TIFs or JPGs.
WIDTH AND HEIGHT
Set width and height to a minimum of the size they will be when printed in the book. Larger is okay. So many designers and illustrators seem to miss the importance of this. The dimensions of an image are just as important as the resolution. If you are creating many of the same types of images such as screen shots, follow the same sizing for each image. All images should be
of the same type to be consistent.
RESOLUTION
300 Pixels / Inch (or more).
COLOR MODE
CMYK Color
BACKGROUND CONTENTS
Select the option that works best for the image you are creating, usually white or transparent.
ADVANCED OPTIONS > COLOR PROFILE
Select U.S. Sheetfed Coated v2, unless using uncoated stock. Verify the color profile with your printer.
Select Create and Save the image, preferably as a tif or as a jpg.
Convert existing images from RGB to CMYK
Check with your printer before you convert images as they may have a particular color profile they use. Star Print Brokers prints books on offset sheetfed presses. They use U.S. Sheetfed Coated v2 for most books.
If books are printed on uncoated or woodfree stock, they use U.S. Sheetfed Uncoated v2. “SWOP” is never used as we do not print on web presses. To convert images in Photoshop, go to Edit > Convert to Profile, and make your selection from the pull-down menu.
COLOR SHIFT
There may be a shift in color when any photo or image is converted from RGB to CMYK. Most often, it appears in blues such as in skies or in hot pink or fuchsia. Photographs with metal colors may also change too. Blues and pinkish watercolor images will likely shift in color. The shifts occur because CMYK has a more limited color array than RGB.
Batch conversion is not recommended. It is important that the client see any shift in color between the original and converted images.
