Home » Adobe Manuals » Computer Software » Adobe 23101335 » Manual Viewer

Adobe 23101335 User Guide - Page 351

Previewing and controlling dithering, Creating background matting in JPEG, images

UPC - 718659152833

Add to My Manuals
Save this manual to your list of manuals

Page 351 highlights

ADOBE PHOTOSHOP 6.0 341 User Guide To create hard-edged transparency in a GIF or PNG-8: 1 Open or create an image that contains transparency. 2 In the Optimize panel/palette, select GIF or PNG-8 from the File Format menu. 3 Select Transparency. 4 Select None from the Matte pop-up menu to make all pixels with greater than 50% transparency fully transparent, and all pixels with 50% or less transparency fully opaque. 3 Select a color from the Matte pop-up menu: • (Photoshop) Select None, Eyedropper (to use the color in the eyedropper sample box), White, Black, or Other (using the color picker). • (ImageReady) Select None, Foreground Color, Background Color, or Other (using the color picker), or select a color from the Matte pop-up palette. Note: When you select None, white is used as the matte color. Creating background matting in JPEG images When creating a JPEG from an original image that contains layer transparency, you must matte the image against a matte color. Since the JPEG format does not support transparency, blending with a matte color is the only way to create the appearance of background transparency in a JPEG. Fully transparent pixels are ﬁlled with the matte color, and partially transparent pixels are blended with the matte color. When the JPEG is placed on a Web page with a background that matches the matte color, the image appears to blend with the Web page background. To create a matted JPEG image: 1 Open or create an image that contains transparency. 2 In the Optimize panel/palette, select JPEG from the ﬁle format menu. Previewing and controlling dithering Most images viewed on the Web are created using 24-bit color displays (millions of colors mode), but many Web browsers are used on computers using only 8-bit color displays (256-color mode), so that Web images often contain colors not available to many Web browsers. Computers use a technique called dithering to simulate colors not available in the color display system. Dithering creates adjacent pixels of different colors to give the appearance of a third color. For example, a red color and a yellow color may dither in a mosaic pattern to produce the illusion of an orange color that does not appear in the color palette.

Section	Page
Table of Contents	3
Getting Started	11
Registration	11
Installing Adobe Photoshop and ImageReady	11
Learning Adobe Photoshop and ImageReady	11
Using Web resources	13
Other learning resources	14
Customer support	15
Adobe Photoshop Basics	19
Using tools and palettes	20
Opening images in Photoshop and ImageReady	22
Streamlining your workflow	24
Making tonal and color adjustments	26
Retouching images	27
Making pixel selections	28
Making edits	30
Using layers	32
Compositing images	34
Painting	36
Drawing shapes	37
Creating type	40
Editing type	41
Designing Web graphics	42
Creating animations (ImageReady)	43
Optimizing Web graphics	44
What’s New in Adobe Photoshop 6.0	49
Superb vector support	50
Enhanced vector output	52
Layer styles	52
Interactive image warping	54
Enhanced slicing capabilities	55
Enhanced support for image maps and rollovers	57
Weighted optimization	58
Improved Web workflow	58
Streamlined interface	59
Enhanced layer management	60
Expanded text features	61
Preset Manager	63
Other new and enhanced features	63
Looking at the Work Area	67
Using the toolbox	67
Using the tool options bar	69
Using palettes	70
Using context menus	74
Viewing images	74
Correcting mistakes	78
Reverting to any state of an image	79
Duplicating images	83
Using rulers, the measure tool, guides, and the grid	84
Working with Extras	87
Displaying status information	88
Displaying file and image information	88
Annotating images (Photoshop)	90
Jumping between applications	92
Previewing an image in a browser	94
Managing libraries with the Preset Manager (Photoshop)	95
Setting preferences	96
Resetting all warning dialogs	97
Monitoring operations	98
Closing files and quitting	98
Getting Images into Photoshop and ImageReady	101
About bitmap images and vector graphics	101
About image size and resolution	102
Changing image size and resolution	105
Scanning images	109
Creating new images	110
Opening and importing images	111
Placing files	114
Managing files with WebDAV	116
Working with Color	119
About color modes and models (Photoshop)	119
Color gamuts (Photoshop)	124
Adjusting the monitor display	124
Channels and bit depth (Photoshop)	126
Converting between color modes (Photoshop)	127
Converting to indexed color (Photoshop)	128
Applying colors	128
Making color and tonal adjustments	128
Producing Consistent Color (Photoshop)	131
Why colors sometimes don’tmatch	131
About color management	131
Do you need color management?	132
Creating a viewing environment for color management	133
Setting up color management	134
Using predefined color management settings	134
Customizing color management settings	136
Specifying working spaces	137
Specifying color management policies	138
Customizing advanced color management settings	140
Saving and loading color management settings	140
Synchronizing color management between applications	141
Soft-proofing colors	141
Changing the color profile of a document	143
Embedding profiles in saved documents	144
Obtaining, installing, and updating color profiles	144
Creating an ICC monitor profile	146
Selecting	149
About selections	149
Making pixel selections	149
Adjusting pixel selections	156
Softening the edges of a selection	157
Moving, copying, and pasting selections and layers	159
Working with snap	162
Saving and loading selections	163
Deleting selections	163
Removing fringe pixels from a selection (Photoshop)	164
Extracting objects from their background (Photoshop)	164
Drawing and Editing	171
About drawing and painting	171
Drawing shapes and paths	171
Using the shape tools	174
Using the pen tools (Photoshop)	176
Drawing overlapping shapes (Photoshop)	181
Using the Paths palette (Photoshop)	181
Editing paths (Photoshop)	182
Managing paths (Photoshop)	189
Converting between paths and selection borders (Photoshop)	190
Adding color to paths (Photoshop)	192
Transforming and retouching	192
Using Channels and Masks	195
About channels	195
Using the Channels palette (Photoshop)	195
Managing channels (Photoshop)	197
Mixing color channels (Photoshop)	200
Adding spot colors (Photoshop)	201
Using channel calculations to blend layers and channels (Photoshop)	204
About masks (Photoshop)	207
Creating temporary masks in Quick Mask mode (Photoshop)	207
Storing masks in alpha channels	209
Using Layers	215
About layers	215
About layer sets	216
Using the Layers palette	216
Creating a layered image	220
Grouping layers into sets	223
Moving and aligning the contents of layers	224
Editing layers	226
Creating clipping groups	228
Specifying layer properties	229
Using the Layer Style dialog box (Photoshop)	230
Setting layer blending options	231
Using layer styles	236
Customizing layer styles	240
Creating and editing contours (Photoshop)	246
Hiding portions of a layer	247
Using adjustment layers or fill layers (Photoshop)	252
Managing layered images	256
Using Type	261
About type	261
Creating type	261
Working with type layers	264
Formatting characters	268
Formatting paragraphs	275
Controlling hyphenation and justification	277
Working with composition	277
Setting options for Chinese, Japanese, and Korean type (Photoshop)	277
Designing Web Pages	281
About designing Web pages with Photoshop and ImageReady	281
Creating and viewing slices	282
Selecting and modifying slices	286
Specifying slice options	291
Creating and viewing image maps (ImageReady)	296
Selecting and modifying image maps (ImageReady)	298
Specifying image map options (ImageReady)	301
Selecting an image map type (ImageReady)	302
Working with rollovers (ImageReady)	302
Creating Web photo galleries (Photoshop)	307
Creating Animations (ImageReady)	311
About animation	311
Creating animations	311
Working with layers in animations	316
Viewing animations	319
Optimizing animations	319
Viewing animated images in Photoshop	320
Saving animations	320
Opening and importing files as animations	321
Optimizing Images for theWeb	325
About optimization	325
Viewing images during optimization	326
Choosing a file format for optimization	327
Optimizing images	330
Using weighted optimization	337
Optimizing colors in GIF and PNG-8 images	340
Working with hexadecimal values for color	347
Making transparent and matted images	349
Previewing and controlling dithering	351
Setting optimization preferences (ImageReady)	355
Using a droplet to automate optimization settings (ImageReady)	356
Saving optimized images	357
Setting output options	358
Creating background images	362
Saving and Exporting Images	367
Saving images	367
About file formats	374
Adding file information (Photoshop)	376
Adding digital copyright information	376
Setting preferences for saving files (Photoshop)	376
Creating multiple-image layouts (Photoshop)	377
Placing Photoshop images in other applications (Photoshop)	379
Printing (Photoshop)	385
About printing	385
Printing images	386
Positioning and scaling images	387
Setting output options	388
Selecting halftone screen attributes	389
Printing part of an image	392
Choosing a print encoding method	392
Printing vector graphics	392
Using color management when printing	392
Printing with Adobe PressReady	393
Creating color traps	394
Printing duotones	394
Printing color separations	399
Automating Tasks	403
About actions	403
Using the Actions palette	404
Recording actions	404
Playing actions	409
Setting playback options (Photoshop)	410
Editing actions	410
Managing actions in the Actions palette	412
Using the Batch command (Photoshop)	415
Using droplets	416
Using the Automate commands (Photoshop)	420
External automation	421
Index	423

Match case Limit results 1 per page

341

ADOBE PHOTOSHOP 6.0

User Guide

To create hard-edged transparency in a GIF or PNG-8:

Open or create an image that contains

transparency.

In the Optimize panel/palette, select GIF or

PNG-8 from the File Format menu.

Select Transparency.

Select None from the Matte pop-up menu to

make all pixels with greater than 50% trans-

parency fully transparent, and all pixels with 50%

or less transparency fully opaque.

Creating background matting in JPEG

images

When creating a JPEG from an original image that

contains layer transparency, you must matte the

image against a matte color. Since the JPEG format

does not support transparency, blending with a

matte color is the only way to create the

appearance of background transparency in a

JPEG. Fully transparent pixels are ﬁlled with the

matte color, and partially transparent pixels are

blended with the matte color. When the JPEG is

placed on a Web page with a background that

matches the matte color, the image appears to

blend with the Web page background.

To create a matted JPEG image:

Open or create an image that contains

transparency.

In the Optimize panel/palette, select JPEG from

the ﬁle format menu.

Select a color from the Matte pop-up menu:

•

(Photoshop) Select None, Eyedropper (to use

the color in the eyedropper sample box), White,

Black, or Other (using the color picker).

•

(ImageReady) Select None, Foreground Color,

Background Color, or Other (using the color

picker), or select a color from the Matte pop-up

palette.

Note:

When you select None, white is used as the

matte color.

Previewing and controlling

dithering

Most images viewed on the Web are created using

24-bit color displays (millions of colors mode),

but many Web browsers are used on computers

using only 8-bit color displays (256-color mode),

so that Web images often contain colors not

available to many Web browsers. Computers use a

technique called dithering to simulate colors not

available in the color display system. Dithering

creates adjacent pixels of different colors to give

the appearance of a third color. For example, a red

color and a yellow color may dither in a mosaic

pattern to produce the illusion of an orange color

that does not appear in the color palette.