Photoshop 6 for Windows Bible- P18

Photoshop 6 for Windows Bible- P18:If you are reading this foreword, it probably means that you’ve purchased a copyof Adobe Photoshop 6.0, and for that I and the rest of the Photoshop team atAdobe thank you.If you own a previous edition of the Photoshop Bible, you probably know what toexpect. If not, then get ready for an interesting trip.
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Photoshop 6 for Windows Bible- P18 Chapter 10 ✦ Corrective Filtering 479 Averaging pixels with Median Another command in the Filter ➪ Noise submenu, Median removes noise by averaging the colors in an image, one pixel at a time. When you choose Filter ➪ Noise ➪ Median, Photoshop produces a Radius option box. For every pixel in a selection, the filter averages the colors of the neighboring pixels that fall inside the specified radius — ignoring any pixels that are so different that they might skew the average — and applies the average color to the central pixel.Photoshop 6 You can now enter any value between 1 and 100. However, even at the old limit, 16, significant blurring occurs, as you can see from the bottom-right example in Figure 10-41 (in the preceding section). At the maximum Radius value, you wind up with a sort of soft, blurry gradient, with all image detail obliterated. As with Gaussian Blur, you can achieve some very interesting and useful effects by backing off the Median filter with the Fade command. But rather than creating a Star Trek glow, Median clumps up details, giving an image a plastic, molded quality, as demonstrated by the examples in Figure 10-42. To create every one of these images, I applied the Median Filter with a Radius of 5 pixels. Then I pressed Ctrl+Shift+F to display the Fade dialog box and lowered the Opacity value to 70 percent. The only difference between one image and the next is the blend mode. Another difference between Gaussian Blur and Median is that Gaussian Blur destroys edges and Median invents new ones. This means you can follow up the Median filter with Unsharp Mask to achieve even more pronounced sculptural effects. I sharpened every one of the examples in Figure 10-42 using an Amount value of 150 percent and a Radius of 1.5. Sharpening a compressed image Digital cameras are the hottest thing in electronic imaging. You can take as many images as you like, download them to your computer immediately, and place them into a printed document literally minutes after snapping the picture. In the next five years, I have little doubt that you — yes, you — will purchase a digital camera (if you haven’t already). Unfortunately, the technology is still very young. And if you’re using one of the mid- or low-priced cameras — read that, under $500 — even the slightest application of the Unsharp Mask filter sometimes results in jagged edges and unsightly artifacts. These blemishes stem from a stingy supply of pixels, heavy-handed compression schemes (all based on JPEG), or both. The situation is improving; cameras at the high end of the consumer price range ($700 and up) can produce 3-megapixel images and often enable you to store uncompressed images in the TIFF format. But as with all good things in life, it will take a while for those options to be available in moderately priced equipment.480 Part III ✦ Selections, Masks, and Filters Normal Screen Darken Lighten Figure 10-42: After applying the Median filter, I reversed the effect slightly using Edit ➪ Fade Median. Although I varied the blend mode — as labeled beneath the images — the Opacity value remained a constant 70 percent. In the meantime, firm up the detail and smooth out the color transitions in your digital photos by applying a combination of filters — Median, Gaussian Blur, and Unsharp Mask — to a layered version of the image. The following steps tell all. Note If you own a digital camera, I encourage you to record these steps with the Actions palette, as explained in Chapter B on the CD accompanying this book. This way, you can set Photoshop to open squads of images, batch-process them, and save them in a separate folder, leaving you free to do something fun, like read more of this book. Chapter 10 ✦ Corrective Filtering 481STEPS: Adjusting the Focus of Digital Photos1. Select the entire image and copy it to a new layer. That’s Ctrl+A, Ctrl+J. Figure 10-43 shows the image that I ...