Photoshop® CS5 Bible

Chapter 14. Sharpness, Blur, and Noise Adjustments

IN THIS CHAPTER

• Using sharpening filters to sharpen images

• Applying an unsharp mask to sharpen images

• Using blurring filters to soften the background in an image

• Simulating a lens blurring effect in a photo

• Reducing noise in images

• Removing dust and scratches from images

A common problem to overcome when working with photos is correcting blurriness and noise. Photoshop provides three classes of filters to overcome these problems: the sharpen, blur, and noise filters. It is important to remember that when you apply filters to an image, you are altering the pixels based on computer algorithms and not optical data. Therefore, the adjustments that Photoshop can make are limited in their effectiveness.

This chapter discusses using the sharpening filters to enhance blurry images and make edges stand out, using blur filters to apply softening effects to images, and using noise reduction filters to remove noise and unwanted artifacts from images.

Note

Sharpening, blurring, and noise reduction are done through the use of filters. Filters are discussed in much greater detail in Chapter 20. Because the use of filters is a fairly destructive adjustment, you should at least review the section in Chapter 20 that discusses creating and using non-destructive Smart Filters before getting too far in this chapter.

Note

When you apply the sharpening, blurring, and noise reduction filters in this chapter as Smart Filters, you can use Blend modes to really change ...