The Darken blending mode is one of the group of modes that darken the picture.

When the top layer is changed to the Darken mode both layers are examined at each part of the picture. When the darkest color is located - it can be from either layer - it is selected as the final color.

Next, the pixels in the top layer are compared to the final color; if they are lighter then they are replaced, if darker they are left unchanged.

Photoshop includes a sophisticated brush engine that, when combined with the program’s ability to make a brush tip from almost any image, allows the user unlimited drawing options to play with.

At the center of brush customization is the Define Brush Preset feature. After using any of the selection tools to outline a part of a picture that will be the new brush tip, select Define Brush Preset under the Edit menu. Name the new brush and click OK. The new tip will now be available at the bottom of the list of brushes in the tool’s options bar.

In the example above a customized Holly Brush tip is created to be used to help decorate a Christmas card. Go to the step-by-step section at the front of this book for a tutorial on how to create your own brushes.

The Custom Shape tool in Photoshop draws a variety of vector-based shapes. The package ships with a variety of premade graphic shapes to choose from but you can also add to this group with shapes that you create yourself.

As the Shape tool uses vector-based artwork as its base, to create your own shape you must use the Pen tool to draw the outline of the design (1).

With the path that outlines your shape complete, select the Define Custom Shape option from the Edit menu and add a name for the shape in the Shape Name dialog that pops up (2).

The newly created shape can now be accessed like an other shape from the Custom Shape Tool library (3).

Custom shapes can also be used in the Shape Blur filter.

Working in a similar way to the Define Brush Preset feature, this option creates and saves a pattern tile for use with tools such as the Pattern Stamp and the Fill command.

To create a new pattern pick Rectangular Marquee tool from the selection tools in the toolbar. Make sure that the Feather and Anti-aliased options are both turned off. Select the picture part that will become the new pattern. Choose the Edit > Define Pattern option and add a new pattern name in the pop-up dialog.

The pattern you create is saved to the bottom of the Pattern Picker (1) menu and becomes available for use immediately after its creation.

No matter how hard you try, when cutting round a subject you usually leave a few pixels from the old background. When you paste the cutout to the new background the unwanted pixels may stick out like a sore thumb. This orange flower, for example, cut out from a typical green foliage background has a few dark green pixels around the edge that show up when it’s pasted to its new blue background. The Defringe command changes these green pixels to orange to produce a cleaner effect. Like most commands, you can enter a pixel value, in this case a width of between 1 and 200 pixels, depending on the nature of your original selection.

The picture above left is the straight cutout and above right is after a defringe value of 50 was applied to the pasted image.

Photoshop has the ability to manipulate and edit single video frames captured from movies, but the photos derived from video sources often need extra processing in addition to the steps usually involved with still pictures.

The process used to record digital video means that photos captured in this way may contain some missing pixels (every second video line). The De-interlace filter is designed to replace this missing picture detail by either interpolating the pixels or duplicating the ones surrounding the area

(1). Interpolation provides the smoothest results and duplication the sharpest.

Also included in the filter dialog is the

option to select which video field to keep and which to eliminate (2). If you are unsure which option to select apply the filter to the image with different options set, creating two example photographs, and then compare the results.

There are four ways to delete a single layer from the layer stack in Photoshop.

• 1. Select the layer in the Layers palette and then drag it to the dustbin icon (Delete Layer button) at the bottom of the palette.
• 2. Select the layer in the palette, click on the Dustbin icon and then select Yes in the confirmation dialog box. To avoid this dialog box hold down the Alt/Option key when clicking the dustbin.
• 3. After selecting the layer to be discarded, choose Layer > Delete Layer.
• 4. Make sure that the layer to remove is selected in the palette then choose Delete Layer from the pop-up menu displayed via the sideways button (top right of the palette).

The contents of active selections can be deleted by pressing the Delete key. This action results in the pixels contained within the selection being converted to the current background color.

The results are the same as selecting Edit

> Cut with an active selection, with the exception that deleting does not store a copy of the selected area on the Clipboard.

In the example, a rectangular selection was made on the surface of the picture before hitting the Delete key. To soften the edges the selection was feathered (1) first before deleting.

The term saturation refers to the vividness of the color in the picture. Desaturating the color reduces the color’s strength in the photograph. Desaturating the image totally removes all color from the picture leaving a grayscale image.

The Hue/Saturation feature (1) in Photoshop is the key control for adjusting the saturation of colors. Moving the middle slider (Saturation) in the dialog to the left allows gradual desaturation of the colors in the picture. Moving the control completely to the left produces an image with no color.

Color can also be removed or enhanced during Raw file editing via the Saturation

(2) or Vibrance sliders (3) in the Adobe Camera Raw feature.

The Desaturate option (4) in the Image > Adjustment menu creates the same effect.

Most professionals don’t convert images to grayscale via the desaturation route, instead they preferred to use techniques that have more control such as those that use the Channel Mixer or Black & White options.

To remove an active selection from the canvas choose Select > Deselect from the menu bar or use the key combination Ctrl/ Cmd D.

Alternatively, you can click anywhere on the canvas outside of the current selection area. This may cause a new selection to be created if you are in the middle of using a selection tool such as the Magic Wand.

Photoshop CS2 introduced some changes to the way that layers are linked/grouped. With this release it became possible to Shift-click layers in the Layers palette to multi-select groups of layers.

The Select > Deselect Layers menu item is one of the commands that can be used in conjunction with the multi-selection of layers. Selecting the option deselects all currently selected layers and leaves no layer active or selected in the Layers palette.

Another way to select multiple layers is to choose the Auto Select Layer and Auto Select Groups options in the Move tool's options bar and then drag a selection marquee around the layers in the workspace.

The Despeckle filter is one of the options in the Noise group of filters. The feature smooths the speckled appearance ofphotos taken with high ISO settings whilst trying to retain as much detail in the original as possible.

The filter isolates the edges and areas of high contrast in the picture before applying its smoothing changes.

As no controls, or preview, are provided with the filter, using the feature is a matter of ‘try it and see'. If the results are unsatisfactory then you can undo the filter changes by selecting Edit > Undo Despeckle.

Generally, better results are obtained using the more sophisticated and controllable Reduce Noise filter. So as a general rule use the Reduce Noise filter for color noise problems and Despeckle for larger areas of more uniform noise.

In Photoshop CS3 all the actions concerning the application of saved or preset Raw conversion settings have been placed under a single menu heading

- Develop Settings.

This menu can be accessed in three ways:

• • via the Edit menu in Bridge,
• • via the Settings icon in the top right of the Adobe Camera Raw dialog (just below the histogram) or
• • by right-clicking on a thumbnail in the Bridge content area.

The Develop Settings menu choices include:

Camera Raw Defaults (1) - Based on the default conversion settings saved for a specific camera or ISO value.

Previous Conversion (2) - Applies the settings from the previous conversion of an image taken with the same camera or ISO value.

copy settings (3) - Used to copy the settings applied to the current image.

Paste Settings (4) - Applies the copied settings from the previous option to a selected image.

Clear Settings (5) - Removes the settings applied to the selected image and returns the photo to its capture state.

User saved settings (6) - Applies one of a list of stored settings created by the user.

Device Central is included for the first time in Photoshop CS3 and the Adobe Suites. The utility is designed to provide an easy way for developers to create and preview content that is destined for display on mobile devices such as phones or PDA (personal digital assistants).

Device Central contains a library of specifications and skins for a range of mobile devices. The specifications provide information on the file types, screen resolutions and media content that is suitable for each device and the skins provide a preview of the content on the device (1).

Users designing for a specific mobile device should start in Device Central. After selecting the make and model use the File > New Document In > Photoshop

(2) to automatically create an image with the dimensions and format suitable for the device.

To preview the photo on the selected mobile device choose File > Save for Web & Devices. Use the new Device Central button

(3) at the bottom right of the dialog to pass the photo to Device Central and preview it on the selected device (1).

Photoshop has five different gradient options. All the gradient types gradually change color and tone from one point in the picture to another.

The Diamond gradient (1) changes color from a center point outwards in a diamond shape.

The Difference blending mode is one of the group of modes that compare and highlight the differences between the top and bottom layers.

By changing to the Difference mode both layers are compared and the color values in the layer (top or bottom), where pixels are brightest, are subtracted from the other layer’s colors. In this way, colors in the top layer can be subtracted from the bottom, or values in the bottom layer can be taken away from the top based on layer brightness.

Blending with a black upper layer produces no change. Blending with a white upper layer inverts the bottom layer’s colors.

The Difference Clouds filter is one of the options in the Render group of filters. The feature fills the document with randomly drawn clouds based on variations in hues ranging from the foreground to background colors.

Applying the filter once creates a basic cloud pattern (1) with colors fluctuating between the foreground and background hues. Applying the filter several times creates a more random effect with new colors and textures entering the picture (2).

The Diffuse filter is one of the options in the Stylize group of filters. The feature softens and diffuses the look of the picture by moving the image pixels around. The effect can be quite subtle and generally more control over the application of diffusion can be obtained using the Diffuse Glow filter.

Four different settings (1) and a preview window are available in the filter dialog.

Normal - Applies the effect randomly throughout all the pixels in the picture.

Darken Only - Replaces light pixels in the photograph with darker ones.

Lighten Only - Replaces darker pixels with lighter ones.

Anisotropic - Applies the soften to all pixels in the picture.

The Diffuse Glow filter is one of the options in the Distort group of filters. The feature adds a strong softening and diffusion effect to the photograph. As a result large areas of tone appear to glow and the whole photograph takes a lighter, more high-key look.

Three slider controls can be found in the filter dialog. The Graininess slider (1) controls the amount of grain-like texture in the resultant photo, the Glow Amount

(2) adjusts the degree that bright colors bleed into the surrounding areas and the Clear Amount (3) determines the strength of the diffusion effect.

The Direct Selection tool is one of a pair of selection tools (1) used for manipulating paths.

Direct Selection tool - This tool is used to select path segments as well as picking up the anchor points on a path made by the Pen tool. Once selected the anchor points can be used to move the entire path, change a point or create a Bezier curve around the subject (2).

To select a path segment with the tool either click onto one of the anchor points or drag a marquee over the segment area.

Path Selection tool - Use this tool to select the whole path by clicking anywhere inside the path boundaries.

1. To select the whole path with the Direct Selection tool Alt/Opt-click inside the path.

2. Ctrl/Cmd-click on an anchor point to activate the

Direct Selection tool.

3. To select additional path segments hold down the Shift key whilst clicking on the segment.

The Lighting Effects filter provides a vast array of options to adjust the way that light is distributed in, or projected on, your photos. One of the options is the lighting type. The choices are:

Omni - Shines light in all directions like a naked light bulb.

Spotlight - Shines light in a beam shaped like an ellipse.

Directional - Shines light as if the light source is far away from the picture.

You can adjust a directional light type in the following ways:

1. Drag the center circle to move the light.

2. To change the direction of the light drag the square end and move it to a separate angle or position in the photograph.

3. To adjust the strength of the light, click and drag the end circle to make the line longer. The shorter the line the brighter the light source.

The Displace filter changes the look of a photo by shifting the position of pixels in the original image. The position and amount of the shift are determined by a displacement map picture which is combined with the original photo as part of the filtering process.

To displace a picture, start by selecting the filter from the Distort menu. Next set the values in the filter dialog (1). In this example I used 100% for both scales, Stretch To Fit and Repeat Edge Pixels settings. Click OK and then choose a displacement map from those saved in the Photoshop/Plug-ins/ Displacment Map folder (2).

Displacement maps are Photoshop files (PSD) that have been designed for use with the Displace filter. The program ships with several examples but you can also make your own.

The amount of displacement in the final picture is based on the tonal value of the map. Dark areas or those pixels with values approaching 0 give the maximum negative shift. Light areas or those with values near 255 produce the maximum positive shift. Middle values (around a value of 128) produce no displacement.

Use the filters and painting tools in Photoshop to create your own maps.

The Dissolve blending mode is one of the group of modes that lighten the picture.

Using the mode blends top and bottom layers using a pattern of pixels. As the opacity of the top layer drops, more of the bottom layer can be seen. The effect is similar to the dissolve transition or editing cut found on many video editing or slide show creation software packages.

Blending when the top layer’s opacity is set to 100% produces no effect. Reduce the top layer’s opacity setting to see the change. The example uses an 80% opacity for the top layer.

The Edit > Transform menu contains six options that allow you to change the shape of your pictures from their standard rectangle format. The Distort feature is one of these options and is used to stretch and squeeze your photos.

After selecting Image > Transform

Pro's Tip

> Distort (1) you may be prompted to change the background to a standard layer ready for transformation. Click Yes in this dialog. Next change the shape of your picture by click-dragging the corner handles to new positions in the document. When completed either double-click on the transformed layer or press the Enter key to ‘commit’ the changes.

To cancel the changes at any time during the distortion process press the Esc key.

Holding down the Alt/Opt key / whilst distorting mirrors the ' changes around the center point of the photo.

A collection of filters that distort the image in a variety of ways. If you have an older computer be patient, some of these filters are memory intensive and apply to your image at a snail’space.

Use these filter options with care. If applied to a full image the results can often look a bit naff. When used creatively on selections within an image the filters can be much more valuable. In the example above the Zigzag filter was used in a selection of just the water.

To control the filtering effect even more try using the Edit

> Fade command directly after applying the filter to the picture.

Many medium to high level digital cameras support saving images in a Raw file format. The format has many advantages for photographers offering them greater control over the tone and color in their files, but there is only one standard available for the Raw files. Each camera manufacturer has their own flavor of the file format.

Adobe developed the DNG or Digital Negative format to help promote a common Raw format that can be used for archival as well as editing and enhancement purposes. As well as including output DNG options in both Photoshop and Photoshop Elements, Adobe provides a free DNG converter that can change proprietary Camera Raw formats to DNG. The converter can be downloaded from www.adobe.com.

To save your Raw files in the DNG format select this option as the file type when saving from the Camera Raw editor (1). In addition to providing a common Raw file format the DNG specification also includes a lossless compression option which, when considering the size of some Raw files, will help reduce the space taken up with the thousands of images that photographers accumulate.

The Info palette contains a variety of details regarding the document that is currently open in the workspace as well as the position of any selected tool. Added to the bottom of the palette in CS2/CS3 is another information panel that displays a range of document and program data (1). By clicking the side-arrow and then selecting Document Sizes it is possible to set up the panel to display. The figure on the left represents an estimate of the file’s size when flattened and saved in the Photoshop format (PSD). The number on the right is the approximate size of the current open file including all layers. As was the case in previous editions of Photoshop you can also find this detail on the left-hand side of the status bar at the bottom of the screen

(2). To change the display select a different option from the pop-up menu.

The Dodge tool lightens specific areas of a photograph when the tool tip is clicked and dragged across the picture surface. The tool’s attributes are based on the settings in the options bar and the current brush size.

The strength of the lightening is governed by the exposure setting. Most professionals choose to keep this value low and build up the tool’s effect with repeated strokes over the same area.

You can also adjust the precise grouping of tones, highlights, midtones or shadows that you are working on at any one time by setting the option in the Range menu.

The term dots per inch started as a measurement of the screen size used by offset printers when converting continuous tone pictures to a series of colored ink dots. It literally refers to the number of dots that would be used in a single inch of a printed picture. The higher the DPI value, the fin er the screen and, therefore, the smaller the dot size. Typically newspapers use a DPI value of around 85 and good quality magazines 150. More recently the term has been used to represent the digital resolution of a photo as well as a measure for scanning resolution. Even though most readers will understand what others mean when they say ‘What is the DPI of that photo?’ or ‘What DPI do you have your scanner set to?’, this is an incorrect use of the term.

PPI - For digital photos the correct unit of measure is PPI or pixels per inch as this describes the resolution of the picture in terms of its primary component - pixels. The picture will only be converted to dots per inch when printed.

SPI - The unit that should be used when discussing scanner settings is SPI or samples per inch. This describes how often the scanning head will sample the information in the photo original per inch.

DPI - As dots per inch started life as a printing term it still has a place in this part of the digital photography process. In fact, in inkjet technology the number of dots laid down by the printer head is often called DPI.

A picture with the same pixel dimensions can be printed to two different sizes by altering the number of pixels per inch that are used in the output process. In this way the same file can be used to output a 5 x 4 inch print (2), or a 10 x 8 inch photo (1), by altering the picture’s resolution (pixels per inch) within the Image Size dialog.

This feature was first introduced in Photoshop 6.0 and was designed to automatically apply a drop shadow to the content of a layer.

All you do is select the layer and then choose the option from the Layer > Layer Styles menu. From the dialog menu (1) you can choose the blend mode, opacity, angle, distance, blur, contour and intensity - play around until you’re happy with the results. Apply the effect by clicking OK.

If the drop shadow style will be used again later use the New Style button to create a new drop shadow style that can be selected from the Layers Style palette.

The Drop Shadow layer style can also be select by clicking the Layer Style button at the bottom of the Layer palette (2).

This feature first appeared in version 6.0 and creates an automated way of applying a prerecorded action.

The droplet is an icon that appears on the desktop that you drag a picture onto to automatically process the prerecorded action.

You may want to set it up to adjust a digital camera picture. Here you could prerecord an action that changes the resolution from 72 ppi to 240 ppi, and adds a faint orange hue to give a feeling of warmth and a touch of Unsharp Mask to improve the clarity of the digital image.

After recording the action select File > Automate > Droplet (1) and alter the

settings in the Create Droplet dialog (2) to suit. This action creates the droplet (3).

Eight-bit grayscale images display up to 256 shades of gray, but a printing press only reproduces around 50 levels per ink. This means that grayscale images printed with black ink look coarser than ones printed with two or more inks.

Duotones are images with two colors (inks) that increase the tonal range of a grayscale image and look stunning when subtly applied. When black is used for shadows and gray for midtones and highlights you produce a black and white image. Versions printed using a colored ink for the highlights produce an image with a slight tint that significantly increases its dynamic range. You need to be in Grayscale mode before you can enter the world of Duotones (Image > Mode > Grayscale). Choose a Duotone preset by clicking on Load and locate it in the Presets folder, or create your own color by clicking on the colored ink squares to call up the color wheel.

Select a color you like and watch the bar at the base of the palette appear as a range of hues from black to white. If you stumble across a Duotone color effect you’d like to keep click on Save and put the *.ado file in a folder. It can then be called up from the Load option when required.

If you’re new to color tone adjustments and only intend printing out on an inkjet printer it would be safer and easier to use the Variations or Hue/Saturation features to tint your RGB files.

The File > Duplicate command makes an exact copy of the current open document in the workspace (1). As well as the picture itself being copied and opened in a new window the feature also duplicates any metadata associated with the photo.

The picture can also be duplicated by right-clicking on the title bar of the document and then selecting the duplicate option (2) from the pop-up menu.

All duplicated files are added to the current folder and are automatically given a file name ending with ‘copy’.

Any layer can be copied and inserted into the current document with the Layer > Duplicate Layer command. Simply select the layer to be copied, choose Duplicate Layer from the Layer menu, insert a new name (2) and choose the destination of the new layer (3) in the Duplicate Layer dialog.

An alternative method to copy a layer is to click-drag the layer from its position in the stack onto the New Layer button in the Layers palette (4). This approach bypasses the Duplicate Layer dialog and simply adds ‘copy’ to the name of the original layer.

A final method for copying a selected layer is to choose the Duplicate Layer (5) option from the right-click menu (Cmd-click -Mac).

The Dust & Scratches filter in Photoshop helps to eliminate annoying spots and marks by blending or blurring the surrounding pixels to cover the defect. The settings you choose for this filter are critical if you are to maintain image sharpness whilst removing small marks. Too much filtering and your image will appear blurred, too little and the marks will remain.

To find settings that provide a good balance, first try adjusting the Threshold setting to zero. Next, use the preview box in the filter dialog to highlight a mark that you want to remove. Use the zoom controls to enlarge the view of the defect (1).

Now drag the Radius slider to the right. Find, and set, the lowest Radius value where the mark is removed (2).

Next, increase the Threshold value gradually until the texture of the image is restored and the defect is still removed (3).