Operation Manual

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USING PHOTOSHOP
Saving and exporting images
Last updated 12/5/2011
• Bicubic Downsampling To Uses a weighted average to determine pixel color, which usually yields better results
than the simple averaging method of downsampling. Bicubic is the slowest but most precise method, resulting in the
smoothest gradations.
Compression Determines the type of compression that is used.
• ZIP compression Works well on images with large areas of single colors or repeating patterns, and for black-and-
white images that contain repeating patterns. ZIP compression is lossless.
• JPEG compression Is suitable for grayscale or color images. JPEG compression is lossy, which means that it removes
image data and may reduce image quality; however, it attempts to reduce file size with a minimal loss of information.
Because JPEG compression eliminates data, it can achieve much smaller file sizes than ZIP compression.
• JPEG2000 Is the new international standard for the compression and packaging of image data. Like JPEG
compression, JPEG2000 compression is suitable for grayscale or color images. It also provides additional advantages,
such as progressive display and lossless compression not available with JPEG. JPEG2000 is only available if Acrobat 6
(PDF 1.5) or later is selected from the Compatibility menu.
Image Quality Determines the amount of compression that is applied. The available options depend on the
compression method. For JPEG2000 compression, Photoshop provides Lossless, Maximum, High, Medium, Low, and
Minimum options. For JPEG compression, Photoshop provides Minimum, Low, Medium, High, and Maximum
options. For ZIP compression, Photoshop provides an 8-bit Image Quality option. The 8-bit Image Quality option is
lossless; that is, data is not removed to reduce file size, so image quality is not affected.
Tile Size Specifies the size of the tiles used in images with JPEG 2000 compression. When low Image Quality values
are used to optimize images smaller than 1024 x 1024 pixels, using the largest tile size produces better results. In
general, a tile size of 1024 is best for most images. Lower tile sizes are generally used for images with small dimensions
(for viewing on devices such as mobile phones).
Convert 16 Bit/Channel Image To 8 Bit/Channel Converts 16-bits-per-channel images to 8-bits-per-channel images
(selected by default). ZIP is the only compression method available if the Convert 16 Bits option is unselected. If your
document’s Compatibility setting is Acrobat 5 (PDF 1.4) or earlier, the Convert 16 Bits option is unavailable, and
images are automatically converted to 8 bits per channel.
Color management and PDF/X options for Adobe PDF
You can set the following options in the Output section of the Adobe PDF Options dialog box. Interactions between
Output options change depending on whether
Color Management
is on or off and which PDF standard is selected.
Color Conversion Specifies how to represent color information in the Adobe PDF file. When you convert color objects
to RGB or CMYK, also select a destination profile from the pop-up menu. All spot color information is preserved
during color conversion; only the process color equivalents convert to the designated color space.
• No Conversion Preserves color data as is.
• Convert To Destination Converts all colors to the profile selected for Destination. Whether the profile is included
or not is determined by the Profile Inclusion Policy.
Destination Describes the gamut of the final RGB or CMYK output device, such as your monitor or a SWOP standard.
Using this profile, Photoshop converts the document’s color information (defined by the source profile in the Working
Spaces section of the
Color Settings