ADDING SHARPNESS
Sharpening is a necessary process no matter how you plan to use your photos.
Generally speaking, there are just two different purposes for an image: electronic and printed. Think about it for a minute. If you take a picture, there are very limited options for how that image will end up. One option is to print it and the other is to use it on the computer (e.g., as an email attachment, a Web document, or even wallpaper).
These two purposes require different levels of sharpening because of the nature of the devices. A printed image requires much more sharpening than one that will stay on the computer. Ink from a printer has a tendency to spread out on paper, causing edges to look a little softer. Also, printed images can far exceed the size of any computer screen. Images viewed on a monitor don’t require as much sharpening because they are typically viewed at much smaller sizes. Consider how much of your image is not visible when you zoom in to 100%—usually quite a bit. This means that you almost never view it at full resolution. Even so, it still requires some sharpening, especially if you reduce the file size.
ADJUST SHARPNESS
There are two different sharpening tools in the Enhance menu. The first is called Adjust Sharpness and can be found by choosing Enhance > Adjust Sharpness. It is a fairly simple tool with just two adjustment sliders, one for sharpness and the other for radius (Figure 5.25). The Amount slider increases the contrast of an edge. As you increase the amount, you are increasing the amount of contrast. The Radius slider controls how far out from the edge the contrast change will take effect. Raising the radius too much can create halos, so only use as much as necessary. If you start to see a bright halo along edges, decrease the radius. I typically use 1.0 to 1.2 pixels for my Radius setting.
FIGURE 5.25
Using the Adjust Sharpness tool.
The Remove option allows you to address different types of softness in your photos, such as lens and motion blur. I usually leave this setting on Gaussian Blur. The More Refined check box tells the tool to look at more subtle edges when sharpening rather than just the obvious hard edges. If you are looking for more detail in textured areas of an image, select this check box; otherwise, you can leave it alone.
Figure 5.26
The controls of the Unsharp Mask tool.
Unsharp mask
Unsharp Mask is probably the most-used sharpening tool. It is similar to the Adjust Sharpness tool in that it uses an Amount slider to control the edge contrast, and a Radius slider for how far out from the edges the sharpening occurs. The big difference is that the Unsharp Mask tool has a Threshold slider for controlling how the sharpness is applied (Figure 5.26). The threshold determines the difference in value between pixels from those in surrounding areas. The higher the number, the less sharpening is applied. If the Threshold setting is left at zero, all of the pixels in the image will be sharpened. I think of the Threshold adjustment as a fade for the sharpening effect.
The important thing to remember when sharpening is to view images at the proper enlargement factor when applying the sharpen effect. If you are going to print a full-size image, zoom in to 100%. Also, I resize my images before applying any sharpening to avoid having to do it more than once.
Assignments
Create Something New with a Crop
Cropping is a great exercise in being able to compose a strong image. Sure, it has practical purposes like straightening a photo or eliminating unwanted items along the edges, but it is also a great creative tool. Open some photos and then use the Crop tool to discover a new image inside the old one. This will also build your compositional skills, which will help when you are actually taking pictures.
Variations Are the Spice of Life
Well, maybe not life, but they can help you with a variety of choices when you’re correcting color or trying to be creative. Use the Color Variations tool to sample some new color creativity in your image.
Sometimes Simple Is Good
As I said earlier in the topic, the Brightness/Contrast tool does not get much respect in the retouching world, but it is actually a refined tool that can improve the look of an image with just a couple of quick slider movements. Find a dull image in your collection and see what a little contrast can do for you.
Take Your Images to New Levels (Adjustments)
The Levels adjustment looks simple on the surface, but it can be a very powerful tool. We will make much more use of it in the next topic, so take some time to get used to all of the controls and how they can be used for adding contrast and correcting colors.
