IMAGE FILE TYPE OVERVIEW

INTRODUCTION TO PHOTOSHOP 4.0 (Continued)

IMAGE FILE TYPE OVERVIEW

MACINTOSH VS IBM COMPATIBLE FILE & DISK FORMATS

Disk Formatting and File Naming Requirements - When moving files between a Macintosh and an IBM-Compatible (or "PC"), follow these rules:

From Macintosh to PC: use DOS-Formatted Diskette. Keep filenames to 7 characters or less. ALWAYS include the proper 3-character extension in the filename.

From PC to Macintosh: In most cases, the Macintosh will accept IBM-formatted diskettes, and most any DOS / Windows 95 filename. Remember to follow the rules "From Macintosh to PC" if you intend to move the files back to a PC later.

GENERAL IMAGE FILE TYPES

PSD (Photoshop Document) - Used by Photoshop. Includes additional file information, including Layers, Masks, Channels, Thumbnail, and Caption / Date / Author info.

EPS (Encapsulated PostScript) - Supported by most illustration and page layout programs. Usually the preferred format for these applications. HINT: When exporting to Adobe Illustrator, convert the document in CMYK Mode before saving it.

TIFF (Tagged Image File Format) - Used to exchange files between applications and computer platforms (i.e., Macintoshes and IBM-compatibles). Supports the LZW compression, a lossless compression scheme.

JPEG (Joint Photographic Experts Group) - Uses an algorithm to compress file size. JPEG compression is lossy. The compression ratio can be custom-set up to 15:1. Used for full-color images on Web pages.

GIF / GIF89a (Graphics Information File) - Created by CompuServe, and used for images and animated graphics on Web pages. GIF89a files can include transparent areas. Uses a Lossless compression scheme with less compression than that possible by JPEG.

BMP (BitMap) - Generally used in Microsoft Windows Applications. The default file type created by Windows Paintbrush.

File Compression - A process using an algorithm to reduce the size of a file.

Lossless Compression - - A file compression scheme that does not discard data when compressing a file. Lets you maintain the quality of the original image, but does not reduce file size as much as lossy compression. Examples include GIF and TIFF

Lossy Compression - A file compression scheme that discards data when compressing a file. While lossy compression can greatly reduce file size, it also reduces the quality of the image. Examples include JPEG.

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Image Basics

Image File Types

Scanning Basics

Photoshop Work Area

Basic Image Correction

How to Scan, Adjust and Save an Image

MACINTOSH VS IBM COMPATIBLE FILE & DISK FORMATS
Disk Formatting and File Naming Requirements - When moving files between a Macintosh and an IBM-Compatible (or "PC"), follow these rules:
	From Macintosh to PC: use DOS-Formatted Diskette. Keep filenames to 7 characters or less. ALWAYS include the proper 3-character extension in the filename.
	From PC to Macintosh: In most cases, the Macintosh will accept IBM-formatted diskettes, and most any DOS / Windows 95 filename. Remember to follow the rules "From Macintosh to PC" if you intend to move the files back to a PC later.

GENERAL IMAGE FILE TYPES
	PSD (Photoshop Document) - Used by Photoshop. Includes additional file information, including Layers, Masks, Channels, Thumbnail, and Caption / Date / Author info.
	EPS (Encapsulated PostScript) - Supported by most illustration and page layout programs. Usually the preferred format for these applications. HINT: When exporting to Adobe Illustrator, convert the document in CMYK Mode before saving it.
	TIFF (Tagged Image File Format) - Used to exchange files between applications and computer platforms (i.e., Macintoshes and IBM-compatibles). Supports the LZW compression, a lossless compression scheme.
	JPEG (Joint Photographic Experts Group) - Uses an algorithm to compress file size. JPEG compression is lossy. The compression ratio can be custom-set up to 15:1. Used for full-color images on Web pages.
	GIF / GIF89a (Graphics Information File) - Created by CompuServe, and used for images and animated graphics on Web pages. GIF89a files can include transparent areas. Uses a Lossless compression scheme with less compression than that possible by JPEG.
	BMP (BitMap) - Generally used in Microsoft Windows Applications. The default file type created by Windows Paintbrush.

File Compression - A process using an algorithm to reduce the size of a file.
Lossless Compression - - A file compression scheme that does not discard data when compressing a file. Lets you maintain the quality of the original image, but does not reduce file size as much as lossy compression. Examples include GIF and TIFF
Lossy Compression - A file compression scheme that discards data when compressing a file. While lossy compression can greatly reduce file size, it also reduces the quality of the image. Examples include JPEG.