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ptg adjustment layer basics IN THIS CHAPTER Creating adjustment layers. . . . . . . .197 Editing the settings for an adjustment layer. . . . . . . . . . . . .199 Saving adjustment presets . . . . . . . .200 Merging and deleting adjustment layers . . . . . . . . . . . . . . . . . . . .201 Editing the adjustment layer mask . .202 Using the Histogram panel . . . . . . . .203 12 You’re happy with the composition of a photo, but it looks a bit dull or the contrast is too strong? Or perhaps the shadows or highlights lack detail? Enter the digital darkroom. Photoshop oers a wide assortment of commands for adjust- ing images, most of which are accessible from the Adjustments panel. In addition to letting you create and edit 15 types of adjustment layers, this panel also provides buttons for viewing, clipping, and restoring your settings. is chapter is devoted primarily to the mechanics of using the Adjustments panel. It also includes an overview of the Histogram panel. Specic adjustment controls are covered in the next chapter. Creating adjustment layers e eects of a command that is applied to a layer via the Image > Adjustments submenu are permanent, whereas the eects of an adjustment layer (applied via the Adjustments panel) become permanent only when you merge it downward into the underlying layer or atten your document. We recommend using adjust- ment layers whenever possible because they’re exible, meaning you can change the settings for them when- ever you like — plus you can restack, hide, show, or delete them, and even drag-copy them between les. Furthermore, adjustment layers don’t increase the le size, so you can create and keep as many as you need. Note: e last six commands on the Image > Adjustments submenu, including the valuable Shadows/ Highlights command, can be applied only via their respective dialogs, not via an adjustment layer. For some of the kinds of adjustment layers that you can create via the Adjustments panel, you can choose a settings preset; for all of them, you can choose indi- vidual settings (you can also modify the settings for a preset). Via the presets, you can apply basic adjust- ments quickly, such as to increase the image contrast using three progressively stronger Levels presets, or to increase the image saturation using progressively stronger Hue/Saturation presets. To create an adjustment layer: 1. Click an image layer. e adjustment layer is going to appear above the layer you have selected. 2. Optional: To restrict the adjustment eect to a specic area of the image, create a selection. Continued on the following page ptg 198 Chapter 12 3. Display the Adjustments panel. e Add an Adjustment buttons and scroll list display. A 4. Do either of the following: Click the button for the desired adjustment type. ey are arranged as follows: tonal adjustments in the top row, color adjustments in the middle row, and miscellaneous adjustments in the bottom row. Click an expand/collapse arrow on the scroll list to expand a category of presets, then click a preset (not all of the adjustment types have presets). 5. Controls for the adjustment layer display on the Adjustments panel, and a new adjustment layer and layer mask appear on the Layers panel. B 6. If you clicked a preset, the controls are already set for you. If you didn’t click a preset or you want to alter the preset settings, choose the desired settings C (and A–B , next page). ➤ To redisplay the Add an Adjustment list when the controls for an adjustment layer are dis- playing, click the Return to Adjustment List button at the bottom of the panel. ➤ To enlarge the Adjustments panel, click the Switch Panel to Expand View button at the bottom of the panel. Click the button again to shrink the panel. ➤ You can also create an adjustment layer by choosing one of the same adjustment types from the New Fill/Adjustment Layer menu at the bottom of the Layers panel. A On the Add an Adjustment list of the Adjustments panel, either click a button to display controls for that adjustment type, or click a preset, if available on the scroll list, to display its predened settings. B Each kind of adjustment layer can be identied by its unique icon, which displays in the layer thumbnail. C  i s i m a g e l a c k s c o n t r a s t . ptg Adjustment Layer Basics 199 A Via the Adjustments panel, we applied the Increase Contrast 1 preset, found in the Levels Presets category. B To darken the midtones and add tonal depth to the photo, we ne-tuned the Levels preset adjustment by dragging the midtones (gray) Input Levels slider slightly to the right. To change the settings for an adjustment layer: 1. On the Layers panel, double-click the thumbnail (icon) for an adjustment layer. e layer becomes selected and the current settings display on the Adjustments panel. (Alternatively, you could also click an adjustment layer, then show the Adjustments panel, in two separate steps.) 2. Do either or both of the following: Edit the settings. For a Levels, Curves, Exposure, Hue/Saturation, Black & White, or Channel Mixer adjustment type, choose a preset from the menu at the top of the panel. ➤ To undo the last individual slider, check box, or other adjustment edit, press Ctrl-Z/Cmd-Z. ➤ To lessen the overall impact of an adjustment layer, lower its opacity via the Layers panel. ➤ To expand or collapse the list of presets for all the available adjustment types, Alt-click/Option- click one of the expand/collapse arrows. ➤ Each time you select and edit an existing adjust- ment layer, those edits are listed collectively on the History panel as one state (e.g., “Modify Levels Layer”). By holding down the View Previous State button, you can display the image temporarily without the new settings you have chosen for the currently selected adjustment layer. To view the image without the latest adjustment changes: 1. On the Layers panel, double-click an adjustment layer thumbnail to select the layer and show the Adjustments panel, then edit the settings. 2. To toggle the latest edits o, press and hold down the View Previous State button or the \ key. To toggle the edits back on, release the button or key. e Reset button on the Adjustments panel either undoes the most recent changes made (if any) to the current adjustment layer since the document was opened, or restores the default settings. e button icon changes depending on whether the settings for the adjustment layer were edited. Run through the following steps, just to see how the button works. To reset an adjustment layer: 1. Double-click an adjustment layer thumbnail to display its settings on the Adjustments panel. 2. Edit the settings. 3. Click the Reset to Previous State button to cancel the current changes and restore the last settings. 4. Click the Reset to Adjustment Defaults button (same button, dierent icon) to restore the default settings. Editing the settings for an adjustment layer ptg 200 Chapter 12 To hide the effect of an adjustment layer: Click the visibility icon on the Adjustments panel or Layers panel; click it again to redisplay. Normally, an adjustment layer aects all the layers below it, but you can clip (restrict) its eect to just the layer directly below it. To restrict the effect of an adjustment layer to the layer directly below it: 1. On the Layers panel, click an adjustment layer. A 2. On the Adjustments panel, click the Clip to Layer button. (Click it again to “unclip.”) B Saving adjustment presets Regardless of how you arrive at custom settings (whether by choosing a preset rst or not), you can save those settings for future use. To save custom adjustment settings as a preset: 1. Create and choose settings for an adjustment layer. Note that presets can be saved only for Levels, Curves, Exposure, Hue/Saturation, Black & White, Channel Mixer, and Selective Color. 2. From the Adjustments panel menu, choose Save [adjustment type] Preset. In the Save dialog, enter a name, keep the default location and extension, then click Save. Your user preset is now available for any document via the Add an Adjustment list on the Adjustments panel, and also via the preset menu at the top of the panel when the controls for that adjustment type (e.g., Levels or Curves) are displaying. ➤ To delete a user preset, choose that preset, choose Delete Current Preset from the panel menu, then click Yes in the alert dialog. A A Levels adjustment layer is being used to intensify the overall contrast in this image. B We clipped the eect of the adjustment layer to just the layer directly below it (the layer that contains the photo of olive oil). ptg Adjustment Layer Basics 201 Merging and deleting adjustment layers When you merge an adjustment layer downward, the adjustments are applied permanently to the under- lying image layer. If you change your mind, either choose Edit > Undo (right away!) or click the prior state on the History panel. To merge an adjustment layer: Do either of the following: Click the adjustment layer to be merged downward, A then press Ctrl-E/Cmd-E. B Right-click on or near the adjustment layer name and choose Merge Down. Note: Adjustment layers don’t contain pixels, so you can’t merge them with one another. However, you can merge multiple adjustment layers into an image layer (or layers) by using the Merge Visible command (see page 145) or the Flatten Image command (see page 146). Adjustment layers are as easy to delete as they are to create. To delete an adjustment layer: Do either of the following: Click the icon for an adjustment layer on the Layers panel, then click the Delete Layer button on the same panel or the Delete Adjustment Layer button on the Adjustments panel. Click Yes if an alert appears. Optional: Click Don’t Show Again to prevent the alert from reappearing. Click the icon or layer mask thumbnail for an adjustment layer on the Layers panel, then press Backspace/Delete. (See also the sidebar at right.) A Click the adjustment layer to be merged downward. B  e M e r g e D o w n c o m m a n d a p p l i e d t h e L e v e l s v a l u e s from the adjustment layer to the underlying image layer, which in this case is the Background. BYPASSING THE AUTO-SELECT PARAMETER OPTION ★ The new Auto-Select Parameter option (on the Adjustments panel menu) causes the fi rst entry fi eld on the panel to become highlighted automatically when you create an adjustment layer or when you double-click the icon for an existing adjustment layer on the Layers panel. Although this option enables you to quickly enter or change values, it can be an annoyance because it prevents some shortcuts from working (e.g., selecting a tool via its letter shortcut or deleting a layer by pressing Backspace/Delete). If this option is on and you want to shift the focus from the Adjustments panel to the Layers panel, click either the icon or the layer mask thumbnail for the adjustment layer. ptg 202 Chapter 12 Editing the adjustment layer mask By default, every adjustment layer has a blank white layer mask. To limit which area of the image the adjustment aects, you can add black areas to the mask, either by lling a selection or by applying brush strokes, as we show you in the steps below. To edit the adjustment layer mask: 1. Click the mask thumbnail on an adjustment layer. 2. Press D to choose the default colors, then press X to switch to black as the Foreground color. 3. To partially mask the adjustment layer eect, do either or both of the following: Create a selection with any selection tool (e.g., Rectangular Marquee or Lasso), choose Edit > Fill (Shift-Backspace/Shift-Delete), choose Use: Foreground Color, click OK, then deselect. Choose the Brush tool (B or Shift-B). On the Options bar, choose a Soft Round brush, Mode: Normal, and an Opacity of 100% (or a lower opacity to create a partial mask), adjust the brush diameter by pressing [ or ], then apply brush strokes to the image. A–C 4. Optional: To reverse the eect of the mask in specic areas, press X to switch colors (make the Foreground color white), then with the Brush tool, apply strokes to remove the mask. ➤ To remove all black areas from the mask, deselect, click the adjustment layer mask, choose Edit> Fill, then choose Use: White in the dialog. ➤ To conne the eect of an adjustment layer to a small area, start with a fully black mask (click Invert on the Masks panel or apply Edit > Fill, Use: Black), then apply strokes with white. ➤ To create a gradual mask by applying a gradient, see pages 244–245. To rene the edge or density of the mask, see pages 170–171. SHORTCUTS FOR LAYER MASKS View the mask by itself in the docu- ment window Alt/Option click the layer mask thumbnail (repeat to restore the normal view) View the mask over the image as a Quick Mask (the default color is red) Alt-Shift/Option-Shift click the layer mask thumbnail (repeat to restore the normal view) Deactivate or activate the mask Shift-click the layer mask thumbnail (Layers panel) or click the Disable/Enable button (Masks panel) Convert the unmasked area into a selection Ctrl/Cmd click the layer mask thumbnail (Layers panel) or click the Load Selection from Mask button (Masks panel) B We used Curves to correct the color, then with the mask for that adjustment layer selected, we applied brush strokes to the top part of the image. Now the adjustment is visible in only the bottom half of the photo. A  i s o r i g i n a l p h o t o l o o k s t o o p i n k . C Our brush strokes are rep- resented by black areas in the adjustment layer mask thumbnail. ptg Adjustment Layer Basics 203 Using the Histogram panel e Histogram panel displays a graph of the current tonal (light and dark) values in an image, which updates dynamically as the document is edited. e panel is always accessible, even while the Adjustments panel is being used or an adjustment dialog is open. You can better judge how adjustment edits are aecting your document if you monitor the changes in its histogram. After opening a photo into Photoshop — but before you begin editing it — study the histogram to evaluate the existing distribution of tonal values in the image. e horizontal axis on the graph repre- sents the grayscale or color levels between 0 and 255, the vertical bars represent the number of pixels at specic color or tonal levels, and the contour of the graph represents the overall tonal range. To choose a view for the Histogram panel: From the Histogram panel menu, choose one of the following: Compact View (just the histogram), A Expanded View (the histogram plus data and access to individual channels), B or All Channels View (all the features of Expanded View, plus separate histograms for each channel). To display document data in the latter two views, check Show Statistics. For Expanded or All Channels view, choose an option from the Channel menu: RGB, C a specic channel, Luminosity, or Colors. To display the individual channels in color, check Show Channels in Color on the panel menu. While a large le is being edited, Photoshop main- tains the redraw speed of the Histogram panel by reading the data from the histogram cache — not from the actual image. When this is occurring, a Cached Data Warning icon appears on the panel. Remember to keep updating the panel, as we instruct you here (even while editing the settings for an adjustment layer), so it will continue to reect the current tonal values of the image. To update the Histogram panel: Do one of the following: Double-click anywhere on the histogram. Click the Cached Data Warning icon. Click the Uncached Refresh button. ➤ To specify a Cache Levels value in the Preferences dialog, see page 391. C With RGB chosen on the Channel menu, the current tonal values in the image are represented by black areas on the graph. B Here the panel is in Expanded View. By default, the Channel menu is set to Colors. A  i s H i s t o g r a m p a n e l i s i n C o m p a c t V i e w . . is too strong? Or perhaps the shadows or highlights lack detail? Enter the digital darkroom. Photoshop oers a wide assortment of commands for adjust- ing images, most of which are accessible. D to choose the default colors, then press X to switch to black as the Foreground color. 3. To partially mask the adjustment layer eect, do either or both of the following: Create a selection. choose a Soft Round brush, Mode: Normal, and an Opacity of 100% (or a lower opacity to create a partial mask), adjust the brush diameter by pressing [ or ], then apply brush strokes to the image. A–C 4.

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