Operation Manual

431
USING PHOTOSHOP
Saving and exporting images
Last updated 12/5/2011
Photoshop recognizes two types of PDF files:
Photoshop PDF files Created when Preserve Photoshop Editing Capabilities is selected in the Save Adobe PDF dialog
box. Photoshop PDF files can contain only a single image.
Photoshop PDF format supports all color modes (except Multichannel) and features that are supported in standard
Photoshop format. Photoshop PDF also supports JPEG and ZIP compression, except for Bitmap-mode images, which
use CCITT Group 4 compression.
Standard PDF files Created when Preserve Photoshop Editing Capabilities is deselected in the Save Adobe PDF dialog
box, or by using another application such as Adobe Acrobat or Illustrator. Standard PDF files can contain multiple
pages and images.
When you open a standard PDF file, Photoshop rasterizes vector and text content, while preserving pixel content.
PICT File
PICT format is used in Mac OS graphics and page-layout applications as an intermediary file format for transferring
images between applications. PICT format supports RGB images with a single alpha channel and Indexed Color,
Grayscale, and Bitmap mode images without alpha channels.
Though Photoshop can open raster PICT files, it cannot open QuickDraw PICTs or save to PICT format.
PICT Resource
(Mac OS) A PICT resource is a PICT file but takes a name and resource ID number. The PICT Resource format
supports RGB images with a single alpha channel, and Indexed Color, Grayscale, and Bitmap mode images without
alpha channels.
You can use the Import command or the Open command to open a PICT resource. However, Photoshop cannot save
to this format.
Pixar format
The Pixar format is designed specifically for high-end graphics applications, such as those used for rendering three-
dimensional images and animation. Pixar format supports RGB and grayscale images with a single alpha channel.
PNG format
Developed as a patent-free alternative to GIF, Portable Network Graphics (PNG) format is used for lossless
compression and for display of images on the web. Unlike GIF, PNG supports 24-bit images and produces background
transparency without jagged edges; however, some web browsers do not support PNG images. PNG format supports
RGB, Indexed Color, Grayscale, and Bitmap mode images without alpha channels. PNG preserves transparency in
grayscale and RGB images.
Portable Bit Map format
The Portable Bit Map (PBM) file format, also known as Portable Bitmap Library and Portable Binary Map, supports
monochrome bitmaps (1 bit per pixel). The format can be used for lossless data transfer because many applications
support this format. You can even edit or create such files within a simple text editor.