We provide these helpful tips as a resource for you. If you don’t
find the information you’re looking for, please give us a call 846-1055
or e-mail us at spgm@ncifcrf.gov.
You want your images to look good, but you don’t want to use
unnecessarily huge files, because they take up space, and can slow down
the performance of your programs, especially in the case of PowerPoint
shows. These tables will help you make sure you’re using your
images in the right format, and at the right
resolution and file size.
Sometimes, when you want an image to look better, what you need is
not higher resolution, but some other kind of image optimization, such
as color balance, contrast and light/dark levels adjustment. If you’re
having trouble with an image, we’d like to help. You can e-mail
us the image and explain the problem, or come over and talk to us.
When you reuse an image file, you’ll need to make sure that
the resolution, file size and file format are appropriate for your purpose.
(See links below.) Always keep the original image file at its maximum
resolution, and make any changes necessary to a copy and save it with
a different name. Keep the original file as a TIF rather than as a JPG
or GIF, as both of these formats sacrifice image quality in order to
achieve a smaller file size. Note: each time you open and resave a JPG,
it is recompressed, and more image quality is lost.
PDF images
Images in a PDF file can often be reused; however, it may not be easy
to extract those images from the document. Also, PDFs can be generated
for a number of purposes, from screen display to professional offset
printing. Therefore, the images in the document may or may not be usable
for your purpose.
JPG
These images can be reused, but you must be cautious about resaving
JPG images, because the JPG compression feature which produces its small
file size, also degrades the quality of the image.
Images in PowerPoint
Images can often be extracted from PowerPoint and reused. However,
those images may not be at sufficient resolution for your purpose, and
the images may not be complete, especially if parts have been imported
into the presentation, and other parts have been added within PowerPoint.
Images in Microsoft Word
Images can often be extracted from Microsoft Word and reused. However,
it is important to make sure those images have sufficient
resolution settings for your purpose.
