Transcript dl_remember
Things to Remember
When working with digital images
What’s your output device?
We prepare images based on our intended use
Output device
• Images for PRINT
• Should have a higher resolution
• Usually in CMYK color mode
• Images for DIGITAL DISPLAY
• Usually have a lower resolution
• Use RGB color mode
Points to Remember
• Create Archival Master
• Scanned at highest level possible - appropriate for
your environment
• Save in uncompressed file format (psd, tiff, eps)
• Create all derivative files from the archival
master
• Back-up Archival Master
Points to Remember
• Image for the web
• Must be compressed, optimized and saved
in a file format readable by browsers
(JPEG, GIF, PNG)
• Compression?
•
The process of reducing the amount of information needed to
display an image file. Compression shrinks the file size which
results in faster download times.
• Lossless Compression method
• Lossy Compression method
Points to Remember
• Optimize?
• The process of selecting the correct file format,
resolution, quality settings for an image so that it
is efficient and usable on the web.
• The ultimate goal is to find a balance between
file size and image quality.
Graphic File Formats
Common Web File Formats
• GIF
Ideal for images with flat areas of color such as logos,
illustrations and cartoons. Supports transparency and
animation. Uses lossless compression to reduce the file size.
• JPEG
Ideal format for photographs or graphics with subtle
gradients. This format supports millions of colors and uses
lossy compression to reduce the file size.
• PNG
PNG-8 similar to GIF and PNG-24 similar to JPEG format.
Supports
Resolution…
• Images for digital display typically have a
lower resolution (72 ppi)
• Image pixels map one-to-one with the
display resolution of a monitor
• Monitor resolution varies by platform and
user configuration
• Monitor resolutions
• http://www.thecounter.com/stats/2006/Septemb
er/res.php
Resolution…
•
High resolution graphics – not needed online. They just
appear larger on screen and take up more file size and
bandwidth.