About
Using Hi-Res "Live" Images
What are "Live" Images? 
A Live image is any image element in an electronic layout file that will be
incorporated into the final proof and film. The distinction "from the desktop"
includes scans, digital photography, Kodak PhotoCD, video frame grabs or computer-generated
art available to most users. Any image on the hard-copy proof that is not
marked "FPO" is typically considered to be a Live image.
A few points to keep in mind when using Live images in your documents:
1) Live images perform best when scanned at the size required in the final product. Consider how you may wish to scale a scanned image as you create the scan. The quality of scanned images will decrease as they are scaled up or down past a certain point.
2) Live images that are to be rotated perform best when scanned at the desired rotation and placed into the page layout application pre-rotated. Algorithms will not have to reposition pixels during the RIP and output; therefore, horizontal and vertical lines may not seem as jagged.
3) Keep the resolution constant between scans so that images look consistent within the same document.
4) When scanning a Live image, be sure to capture enough image to fill the desired space. Because layout programs typically place pictures/graphics in a box or frame, it is necessary to capture at least an extra 3 millimeters (18") so that it will fit behind the edges. If the image bleeds, then capture enough to account for the bleed.
5) Any Live image files should be supplied in a CMYK color model Ð not the RGB model scanners typically provide. You can have the scans converted to CMYK on-the-fly with a high-end scanner that supports this feature, or you can do it after the fact with an image editing program.
6) Our output systems work more efficiently with composite image formats such as EPS, TIFF or DCS. If your images are saved in a pre-separated format (DCS), these separations will have to be recombined if any manual trapping is required.
Live Images and Resolution Issues
As a general rule, the scanned image (placed at 100% of final size) should
have a minimum pixels-per-inch (ppi) sampling of 1.5 times the output line
screen. Finely-detailed images or images intended for lenticular printing
may be sampled at up to 3.0 times the output line screen. For example, an
image that you plan to print using a 200 line screen may need a resolution
of 300 to 600 pixels per inch, depending on the detail in the image. Remember,
this is at 100%. If you scale your image, you are changing the effective resolution.
The goal in scanning Live images is to capture enough data to achieve the
desired detail and keep file size as small as possible at the same time.
Avoid resizing or scaling images in a page layout application. Scaling of
live images should be done in a prefessional photo manipulation application
where resampling will take resolution into consideration. Be aware that increasing
image resolution above what was provided in the original scan can only be
done through interpolation. The software makes intelligent guesses about what
information to add. The results are never as good as scanning for the desired
size and resolution, and can be significantly less so.
Click here for more Scanning Tips.
Live (Vector) Images Created in Illustration Applications
When an EPS file from an illustration application is opened and saved in Photoshop™,
it is converted from an object-oriented image to a scan-like bitmap image.
It will no longer maintain hard, clean edges on the page.
Soft shadows on top of a background scan require retouching and merging of
the shadow and the background images on the Live scan.
Always restrict files that are to be placed in a page layout application to
single-subject files. For example, don't put multiple logos in one EPS file
if they are to be individually cropped in your layouts. Each time you place
an uncropped EPS file, the PostScript RIP has to process the entire EPS file,
even though only a small part is showing through the cropped windows. This
can result in huge productivity losses.
It often may be appropriate in an illustration to convert text to outlines
to eliminate font calls and ensure font compatibility at production time.
This method is good for a small number of words or an obscure font. It can,
however, be bad for more than a few words or small type sizes. For example,
outlining tiny type can create shapes too complex to print. Converting text
to outlines means edits become more complex since the image is now a graphic
instead of a font. Also, the quality of the outlined/pathed font will likely
represent a minimal degradation from the original font design. Converting
text to outlines/paths is typically used for headlines, foreign language copy
and logo treatments.
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