The Halftone Pattern filter, as one of the group of Sketch filters, simulates the look of a picture that has been printed using a halftone or screened pattern. The filter provides similar looking results to the Color Halftone feature except here the pattern is created in monochrome and is based on the current foreground and background colors. Another difference is that the filter contains a preview window and the ability to change the pattern type (3).

The size of the pattern element (1), dot or line, and the overall contrast of the effect (2) is controlled by the sliders in the dialog. The pattern type can be switched between dot (4), line (5) or circle (6) options.

The Hand tool helps users navigate their way around images. This is especially helpful when the image has been ‘zoomed’ beyond the confi nes of the screen. When a picture is enlarged to this extent it is not possible to view the whole image at one time; using the Hand tool the user can drag the photograph around within the window frame.

The Hard Light blending mode is one of the group of Overlay modes that base their effects on combining the two layers depending on the tonal value of their contents.

This option is similar to the Overlay mode but produces a more dramatic and sometimes more contrasty result. The content of the top layer is either Screened or Multiplied depending on its color and tonal value. If the tone in the top layer is lighter than 50% then this section of the bottom layer is screened (lightened); if the tone is darker, then it is multiplied (darkened). Blending with 50% gray produces no change. When combined with the High Pass filter this blend mode is used to create editable sharpening effects that don’t use any of the sharpening filters.

The Hand tool helps users navigate their way around images. This is especially helpful when the image has been ‘zoomed’ beyond the confines of the screen. When a picture is enlarged to this extent it is not possible to view the whole image at one time; using the Hand tool the user can drag the photograph around within the window frame.

The Hard Mix blending mode is one of the group of Overlay modes that base their effects on combining the two layers depending on the tonal value of their contents.

This option is similar to the Overlay mode but produces a more dramatic, contrasty and posterized result. The luminosity of the top layer is combined with the color of the bottom to produce a picture with large flat areas of dramatic color (maximum colors 8). Lowering the opacity of the top layer (Hard Mix layer) reduces the posterization effects. Blending with 50% gray produces no change.

The Hard Mix option can be used to add a high contrast sharpening effect to a picture. Blur a duplicate layer of the original and then change to Hard Mix and adjust the layer’s opacity to control the degree of contrast and sharpening.

Hardness (4) is one of the options from the Brush Preset Picker palette, which is displayed when the down-arrow button is pressed in the options bar. The slider controls the softness of the edge of the brush tip. A setting of 100% (1) produces a sharp edged brush stroke, 50% moderately soft (2) and 1% a very soft brush stroke (3).

To create a High Dynamic Range image in Photoshop you need to capture at least three separate pictures of the same subject with different exposures.

Most digital cameras have a built-in option for exposure bracketing and using this feature will mean that you can photograph a sequence of pictures and the camera will alter the exposure settings to record over-, under- and correctly exposed frames automatically.

Be sure that the camera is changing the shutter speed to alter the exposure as adjusting the aperture will cause changes in the depth of field of sharpness as well. Photoshop CS3 increases the features available for use with HDR files. Now both the Levels and Hue/Saturation commands are available for use with these files.

The Exposure feature is designed to adjust the contrast and brightness of the 32 bits per channel or HDR pictures. With this dialog you can make basic adjustments to image tones before converting the file to 16 or 8 bits per channel mode for further editing.

The Channel Mixer, Levels, Hue/ Saturation, Auto Levels, Auto contrast, Auto color correction and Photo filter adjustment features can also be used with HDR images.

Changing from 32 bits per channel mode to either 8 or 16 bits per channel displays the HDR Conversion dialog. In this feature it is possible to control how the many tones contained in the high-bit image are compressed into a lower-bit mode format. You can select from four conversion methods (1). The Exposure and Gamma option uses two slider controls to adjust the positioning of tones prior to conversion. Highlight Compression and Equalize Histogram selections both provide automatic tonal adjustment with no user controls.

In the final option, Local Adaptation , a familiar curves feature can be used to determine which tones are compressed and by how much. A steep line indicates greater contrast and less compression of tones whereas a shallow part of the curve compresses the tones more radically and results in image areas of lower contrast.

The Healing Brush is designed to work in a similar way to the Clone tool; the user selects the area (Alt/Option-click) to be sampled before painting and then proceeds to drag the brush tip over the area to be repaired.

The tool achieves such great results by merging background and source area details as you paint. Just as with the Clone Stamp tool, the size and edge hardness of the current brush determines the characteristics of the Healing Brush tool tip (1).

One of the best ways to demonstrate the sheer power of the Healing Brush is to remove the wrinkles from an aged face. In the example, the deep crevices of the fisherman’s face have been easily removed with the tool. The texture, color and tone of the face remain even after the ‘healing’ work is completed because the tool merges the new areas with the detail of the picture beneath.

In CS3 the Healing brush can be used nondestructively with the Sample All Layers option. Just add a new blank layer above the background and with the Sample All Layers option selected clone paint in the retouching changes to the new layer.

Though there has always been a great Help system in Photoshop, CS2 introduced a revised version of the feature and CS3 continues this development.

The Help Center displays topics in a Viewer palette that is independent of the main program (1). And unlike previous Help options searches for particular topics display entries not just for the program you are working with but across the whole suite of Adobe products that you have installed (2).

Other changes include linked video tutorials on specific topics and listing of Help entries in ways that provide quicker and easier access not just to information about a particular subject but also how to use the tool or feature in a fuller workflow.

Open palettes can be hidden and redisplayed by pressing the Tab key (1). To close the palette altogether click the red ‘X’ in the top right corner of the palette window. Alternatively palettes open in the workspace can be dragged to the palette dock, where the palette is minimized and displayed as a single tab. Palettes can then be displayed by clicking on the tab or displayed and removed from the dock by double-clicking.

The Photoshop Layers palette displays all the layers in your picture and their settings in the one dialog box. Layers can be turned off by clicking the eye symbol on the far left of the layer so that it is no longer displayed. This action removes the layer from view but not from the stack. You can turn the layer back on again by clicking the eye space. You can Alt/Option-click on an Eyeball icon to show all layers or just that layer.

Photoshop CS2 introduced the ability to create and apply basic edits to 32 bits per channel digital photos. CS3 builds on the features set that can be used with this high-bit file type.

Most digital camera sensors are capable of capturing a brightness range of between 6 and 8 f-stops between deepest shadow and brightest highlights. For most shooting scenarios this range, often called the dynamic range of the sensor, equates to the contrast of the scene. So when photographing a scene with average brightness range the detail is captured and held throughout the whole file. However, in particularly bright or contrasty environments (summer in the tropics) or when capturing a view that encompasses an inside space as well as a brightly lit exterior, the abilities of the sensor will be exceeded. This results in detail being lost in the highlight and/or the shadow area of the picture. To help solve this problem Adobe has created a new set of tools that can be used to combine the brightness range of several different pictures to create a High Dynamic Range or HDR picture.

To create an HDR picture start by shooting at least three pictures of the same scene with exposure differences of 2 f-stops or more. (See HDR, capturing source images entry for more details.) Next, load the three files into the File > Automate > Merge to HDR feature (1). Photoshop will attempt to register the three pictures and determine the exposure difference between each using the metadata stored with the original camera file. If the exposure detail is not found or is stored in a format that isn’t accessible by the feature then you will need to inform Photoshop of the exposure settings used to capture each photograph. This is entered via the Manually Set EV dialog (2). The Merge to HDR dialog (3) displays the combined image, thumbnails of the source pictures, as well as a Set White Point preview option. In CS3 there is also an option to Save/Load Response Curves for use across a range of similar images. The finalized HDR file can then be used as a basis for conversion to 8 or 16 bits per channel files.

HDR options in CS2:

In Photoshop CS2 the following features and tools are 32-bit enabled: Crop, Image, Canvas Size, Trim, Free Transform, Selection (save and load), Clone Stamp, History Brush, Info palette, Channel Mixer, PhotoFilter and Exposure Adjustments as well as Add Noise, Unsharp Mask, Gaussian Blur, Motion Blur, Offset, High Pass, Lens Flare, Smart Sharpen, Average, Box Blur, Motion Blur, Radial Blur, Shape Blur, Surface Blur, DeInterlace, NTSC filters.

Additional HDR options in CS3:

In CS3 you also have layer support, Levels and Hue/Saturation adjustments, Normal, Dissolve, Behind, Clear, Darken, Multiply, Lighten, Linear Dodge (Add), Difference, Hue, Saturation, Color, and Luminosity blend modes, Fill, Stroke, and Transform commands, Average, Add Noise, Clouds, Fibers, Lens Flare, Smart Sharpen, Emboss, Maximum and Minimum filters, New layers, duplicate layers, adjustment layers (Levels, Hue/Saturation, Channel Mixer, Photo Filter, and Exposure), fill layers, layer masks, layer styles, supported blending modes, and Smart Object layers, Invert, Modify Border, Transform Selection, Save Selection and Load Selections,

The High Pass filter, as one of the group of Other filters, isolates the edges in a picture and then converts the rest of the picture to mid gray. The filter locates the edge areas by searching for areas of high contrast or color change.

The filter contains a single slider, Radius (1), that controls the filtering effect. When the Radius value is set to low only the most prominent edge detail is retained and the remainder of the picture converted to gray. Higher values produce a result with less of the picture converted to gray.

The combination filter effects of edge finding and changing picture parts to gray make this feature a tool that is often used for advanced sharpening techniques like the one detailed here.

These can be adjusted using the clear triangle on the slider control (white point input slider) that appears on the right-hand side of the Levels graph (2).

The Shadow/Highlight feature provides another way of controlling the density (brightness) of the highlights in your pictures (3).

The first step in taking charge of your pixels is to become aware of where they are situated in your image and how they are distributed between black and white points.

The Histogram palette displays a graph of all the pixels in your image. The left-hand side represents the black values (1), the right the white end of the spectrum (3) and the center section the midtone values (2). In a 24-bit image (8 bits per channel) there are a total of 256 levels of tone possible from black to white - each of these values is represented on the graph.

The number of pixels in the image with a particular brightness or tone value is displayed on the graph by height. The higher the spike at any point, the more pixels of this value are present in the picture.

A low-key image appears with most of the peaks concentrated in the shadow area at the left-hand side. A high-key image has the peaks in the highlight area to the right. The average tone image should have a graph that rises from the far left, peaks across the middle section and falls to the far right.

Use this to paint in details from a previous stage of editing. Click on the box that appears in the History palette at the stage in the image-editing process that you’d like to apply and paint onto the new level.

This is a great option if you’re considering hand-coloring a black and white image. Cheat by starting off with a color image and convert it first to grayscale to discard all color information and then back to color. The black and white image can then be colored using the History brush.

Click on the left of the opening image to turn on the History brush icon. Then click on the latest stage and begin to paint.

The feature is also good for removing dust and scratches. Apply the Dust & Scratches filter and make the History brush active on that new layer. Then go back to a previous history level and paint with the History brush over dust and scratches to paint in the newer filtered layer.

First released in CS the History Log feature is an option that records all actions that you perform in Photoshop.

The log can be saved as metadata that is attached to the picture or as a separated text file. When the History Log is saved as metadata the contents can be viewed via the File > Info palette (1).

Settings that govern the type of log created, as well as where it is stored, can be found in the Edit > Preferences > General dialog (2). Also located in this dialog is the option to turn the feature off and on.

Every task you perform in Photoshop is recorded as a step, or state, and then displayed as a list in the History palette. Working like a multiple level Undo feature this allows you to go back through previous stages of your image editing and correct changes that went wrong.

A slider on the left-hand side of the palette can be dragged slowly through the stages to help you find when things start to go wrong. Simply click on the last stage that you were happy with and start again to change history - if it were only just that simple in life!

The number of states stored in the palette is controlled by the value set in the Edit > Preferences > General dialog. States are deleted by selecting the entry in the palette and then pressing the Dustbin button (1) at the bottom of the palette. A new document can be made from a state by clicking the New Document button (2). A snapshot or temporary copy of any given state that is displayed at the top of the palette can be created with the Snapshot button (3).

Each editing or enhancement step that is performed on a picture in Photoshop is stored as a history state in the History palette.

The total number of states that can be stored is determined by the History states setting in the general area Preferences dialog. Once this number has been reached the oldest state is deleted to make way for the latest image change.

Clicking on an earlier state will restore the picture to the way it was when the state was first added to the palette.

The Photoshop Type tool provides the option to apply text horizontally across the page, or vertically down the page.

To place text onto your picture, select the Horizontal Type tool from the toolbox. Next, click onto the canvas in the area where you want the text to appear.

Do not be too concerned if the letters are not positioned exactly, as the layer and text can be moved later.

Once you have finished entering text you need to commit the type to a layer. Until this is done you will be unable to access most other Photoshop functions.

To exit the text editor, either click the ‘tick’ button in the options bar or press the Control + Enter keys in Windows or Command + Return for a Macintosh system.

The Hue blending mode is one of the group of modes that base their effects on combining the hue (color), saturation (color strength) and luminance (tones and details) of the two layers in different ways.

This option combines the hue of the top layer with the saturation and luminance of the bottom.

To understand how this feature works you will need to think of the colors in your image in a slightly different way. Rather than using the three-color model (Red, Green, Blue) that we are familiar with, the Hue/Saturation control breaks the image into different components - Hue or color, Saturation or color strength, and Lightness (HSL).

The dialog itself displays slider controls for each component, allowing the user to change each factor independently of the others. Moving the Hue control (1) along the slider changes the dominant color of the image. From left to right, the hue’s changes are represented in much the same way as colors in a rainbow. Alterations here will provide a variety of dramatic results, most of which are not realistic and should be used carefully.

Moving the Saturation slider (2) to the left gradually decreases the strength of the color until the image is converted to grayscale. In contrast, adjusting the control to the right increases the purity of the hue and produces images that are vibrant and dramatic.

The Lightness slider (3) changes the density of the image and works the same way as the Brightness slider in the Brightness/Contrast feature.

The Colorize option (4) converts a colored image to a monochrome made up of a single dominant color and black and white.

If Master is selected in the Edit menu, changes will affect the entire image. You can also select different color ranges from the menu and changes will affect only the selected color range.

The Hue/Saturation adjustment layer provides the same functionality as the Adjust Hue/Saturation feature.

Manipulating the picture with an adjustment layer rather than directly means that the original picture is always kept intact and you can always change the settings of the adjustment later by double-clicking on the left-hand layer thumbnail.