| home / graphics / elements / 1 |    [previous] [next] |
|
|
|
Sometimes, regardless of how much you increase the strength, Smart Fix doesn’t do the job. Look at Figure 2.5. I tried using Smart Fix, but it was way off. Instead I’ll try another method, Auto Levels.
Figure 2.5: Smart Fix didn’t work on this image.
Auto Levels finds the darkest and lightest pixels of an image and then remaps the intermediate pixels proportionately. Color casts may be removed or introduced because Auto Levels adjusts the red, green, and blue channels individually.
In Standard Edit, you apply Auto Levels via the menu bar (Enhance > Auto Levels) or via the keyboard (Shift+Ctrl+L / Shift+ +L). In Quick Fix, in the Lighting group in the Control Center, click Auto next to Levels.
That’s what I did to the shot, and you can see in Figure 2.6 that it worked. Figure 2.7 shows the image’s histogram before and after Auto Levels. Notice that the fixed shot has a much better distribution of tonal values.
Figure 2.6: After Auto Levels.
Figure 2.7: The image’s histogram before Auto Levels ( left): a narrow distribution of tonal values. After Auto Levels (right): a wider distribution of tonal values.
Auto Contrast, by the way—found just under Auto Levels in the Enhance menu and in Quick Fix under Lighting—isn’t nearly as useful for color images. It adjusts the overall contrast and mixture of colors but it does not adjust each color channel (red, green, and blue) individually. I rarely use Auto Contrast, and when I do it’s mostly for grayscale images.
The Lighten Shadows, Darken Highlights, and Midtone Contrast commands found in the Quick Fix Control Center are basically the same commands you get when you choose Enhance > Adjust Lighting > Shadows/Highlights from the main menu bar. These controls are very useful when you want to correct images with a strong backlight and a dark foreground, or vice versa. I’ll use these commands later, in Chapters 3, 4, and 7 (When you adjust the Lighten Shadows, Darken Highlights, and Midtone Contrast sliders, Commit and Cancel icons appear next the word Lighting. Select Commit when you are satisfied with the image. Select Cancel if you are not. Until you select either the Commit or Cancel icon, the Reset button located above the After version of your image is dimmed and inoperable).
The Auto Levels command also doesn’t always work satisfactorily. The bag in Figure 2.8, shot with a digital camera for a commercial website, lacks color intensity and contrast. But applying Auto Levels makes it look worse. At times like this, I turn to the Levels controls found in the menu bar under Enhance > Adjust Lighting > Levels. (You also have access to Levels from Quick Fix). The truth is, I probably use Levels more than any other single Photoshop Elements control. It enables me to manually adjust the intensity of my shadow, midtone, or highlight areas. Not only does it give me sophisticated control over the look of my digital images, it is intuitive and relatively easy to use.
Figure 2.8: The original image (left) lacks color intensity and contrast. Auto Levels didn’t help (right).
1. Here is how I used Levels to make the bag look more attractive and saleable: I chose Enhance > Adjust Lighting > Levels. This opened the dialog box shown in Figure 2.9.
Figure 2.9: Levels graphically show the distribution of tonal values and provide a means to individually adjust shadows, midtones, or highlights.
2. Looking at the Levels histogram, I saw the problem. Most of the values were to the left, toward the shadow areas. I needed to spread the values across the spectrum and increase the contrast. To do this, I dragged the Input Levels white triangle (at the lower-right corner of the histogram) to the left, toward the edge of the tall black mound. As I did this, I saw the whites, or highlights, in my actual image lighten and the overall contrast increase. (Be sure you have selected the Preview check box in the Levels dialog box. With this option selected, any changes you make in the Levels dialog box will be shown in the actual image).
3. Next I adjusted the midtones by dragging the Input Levels gray triangle (found in the middle of the bottom edge of the histogram) to the right. This darkened and intensified the midtones. The numbers in the three boxes above the histogram represent numerically, in order, shadows, midtones, and highlight areas. As you move the triangle sliders, you’ll see these values change to reflect the new values. You can also enter numeric values into these boxes, but it’s a lot easier to manually slide the sliders.
4. At various points in the process, I found it useful to carefully examine the effects of my changes on detailed parts of the image. For example, when I adjusted the midtones, I wanted to make sure I didn’t lose any details in the gold embroidery. Even though the Levels dialog box was open, I could still use my navigation keyboard commands to magnify and scroll around the image. (This works only in Standard Edit, not in Quick Fix).
5. The shadow areas (again, represented in the left side of the histogram) looked fine, but I went ahead and moved the black triangle anyway. In Figure 2.10, you can see how I adjusted the Levels so that the shadow areas became too dark. At this point I could have slid the black triangle back to its original position, but I decided to start over completely and reset the image to its original state. To do this, I held down the Alt/Option key and clicked the Reset button in the Levels dialog box.
| home / graphics / elements / 1 | [previous] [next] |
Legal Notices, Licensing, Permissions, Privacy Policy.
Advertise | Newsletters | Shopping | E-mail Offers | Freelance Jobs 
Created: March 27, 2003
Revised: November 30, 2004
URL: http://webreference.com/graphics/elements/1
