1. If your efforts to reduce noise result in more image softening than you find acceptable, you can try to reuse the Sharpening sliderbut don't be surprised if you find yourself going 'round in circles. The same precautions outlined in the "Sharpening" section pertain here as well. 4.3.4. Using the Lens Tab Settings The Lens tab is used to minimize a digital phenomenon called fringing and the vignetting that occurs most noticeably with bargain-priced wide-angle lenses. You can see the Lens tab in Figure 4-18. Figure 4-18. The Lens tab. NOTE These settings follow the same workflow advice as I gave earlier: if your goal is maximum image quality, no matter how long it takes, rely on the power of Photoshop. If you need a quick turnaround, it's best to make the photo look as good as possible before you send it out of Camera Raw and straight to your client. 4.3.4.1. Eliminating vignettes We'll work with the settings for eliminating vignetting first just because they're dead simple and also because they can be used to create vignettes as well. Vignettes are often the result of cheap optics or of the use of filters or lens hoods that are too small to cover the entire angle of view of the lens. They tend to show up more in wide-angle opticseven more so if you have a camera with a full 35mm- size sensor. In extreme cases, you can spot vignetting when you see a gradual darkening around the edges of the photo. In Figure 4-19, I have intentionally exaggerated the vignetting to make it easier to see what it looks like. Figure 4-19. Noticeable vignetting caused by a fully zoomed out wide-angle lens. On the right, it has been corrected by the Lens tab's Vignette slider. There are, by the way, two types of vignettes: dark-edged and light-edged. Moving the slider to the right makes the vignette lighter; moving it to the left makes it darker. If it's dead center (the default position), the slider has no effect at all. If you have never corrected your edges for vignettingprobably because you didn't think it existedtake a few of your widest angle photos and try correcting them by dragging the vignette slider slightly to the right. If the corners brighten just enough that the whole image looks more "even," your lens probably has a slight amount of vignetting. The chances are particularly good if the lens is a 28mm or wider 35mm equivalent and has not been stopped down more than one or two f-stops. Now, here's the interesting part: you may want to use this slider to create a vignette. After all, vignettes can be very effective in focusing viewer attention on the center of the image. Usually, I recommend doing that on a masked adjustment layer in Photoshop so you can turn the layer on and off to show your client (or yourself) the difference. However, if you want to save a layer and still do it nondestructively, here's your big chance. When you're correcting a vignette, you usually want to keep it centered in the frame. However, when you're creating one, you may want to be able to control the location of the center. However, you can't do that until you create the vignette itself. To make the vignette darker, drag the slider to the left. To make it lighter, drag it to the right. Now you can move the center up or down. Simply drag the bottom slider and watch the vignette move until the vignette is positioned as you'd like it. You can see the result in Figure 4-20. Figure 4-20. The result of creating a vignette. 4.3.4.2. Minimizing color fringing Color fringing (aka chromatic aberration) comes in two flavors: Red/Cyan and Blue/Yellow (see Figure 4-21). Camera Raw, once again, isn't the most sophisticated tool on the planet for getting rid of this "fringe," but it's handy, nondestructive, and quick. Figure 4-21. Red/Cyan (left) and Blue/Yellow (right) color fringing is easiest to spot along high-contrast edges. Once again, color fringing is a phenomenon you're most likely to see with small sensors, high ISO settings, and cheap optical construction. So if you can afford the best shooting gear, you won't encounter it much. If you do, here are the steps to get rid of it: 1. Select all the similar images that are likely to show chromatic aberration and open them at the same time in Camera Raw. Be sure to click the Select All button. 2. Double-click the Zoom tool. In the Preview window, all the images will be enlarged to 100 percent. Now, move the cursor to the middle of the Preview window and click once more. You are now zoomed in 200 percent. Use the Hand tool to move the image around until you find some sharp, highly contrasting edges. 3. Oh, I almost forgot. You want to make sure your fringing isn't the result of over-sharpening. So before you go any further, click the Detail tab and take a look at the Sharpening slider. Make sure its slider is all the way to the left. If not, just put it there. Then go back to the Lens tab. 4. Now look carefully along your high-contrast, hard edges. Do you see any pure Red, Cyan, Blue, or Yellow lines that are parallel to those edges? If you do, you got fringing, baby. Don't panicfix it. 5. If the worst fringe lines are Blue or Yellow (and they usually are), drag the Blue/Yellow slider to the left until the Blue disappears or to the right until the Yellow disappears. You won't see both of these colors. You might, however, see some Red or Cyan fringe lines. If so (you guessed it), move the Red/Cyan slider left to get rid of red fringe, or to the right to get rid of blue fringe. 4.3.5. Using the Calibrate Tab Settings Camera Raw in CS2 has another new tab, Calibrate (Figure 4-22), which allows you to adjust the way your camera's sensor interprets color. You can adjust the color tint of shadows to make them more neutral by changing the green or magenta. You can also adjust how the sensor interprets each of the primary colors in respect to Hue and Saturation. You'll also learn to save those settings to reuse later or use on other images. Figure 4-22. The new Calibrate tab. One of the beauties of RAW file processing is that, for most purposes, you don't really need to calibrate your camera. This is because you have so much flexibility in interpreting the image in Camera Raw that the exact interpretation of the image can cover a huge range. The exception is situations in which you are shooting a product or scientific assignment in which a specific color must be reproduced exactly (e.g., the color and shade of clothing in fashion advertising or company logos when in a prominent portion of the photograph). Before someone protests, it is true that Camera Raw is powerful enough to let you match colors without calibrating your camera. If your monitor has been calibrated to a very precise level, you could simply match colors by placing the object next to the monitor and then making adjustments in Camera Raw to match the color of the object. That's a good thing, because there will be timessuch as when the client sends you a RAW file that you didn't shootwhen you have no other alternative. It is desirable, however, to calibrate your camera because it can save you hours of Camera Raw time. Besides, the more accurate your original exposure, the more latitude you have in interpreting that shot. NOTE I've already mentioned using gray cards and color cards. If you're using only a gray card, don't expect your calibration to be good enough to accurately reproduce specific subject colors. However, your image will represent reality much more accurately and I'd advise saving the profile if you are likely to find yourself in that situation again. The tools you use to calibrate your camera sensor are in the Calibrate tab. These happen to be the same tools you'd use to subjectively change your camera's interpretation of color and detail. I'll give you procedures for using the Calibrate tab for both purposes. To use the Calibrate tab to subjectively tweak the interpretation of individual primary colors: 1. Click the Calibrate tab. The Camera Profile menu will show only the current version of ACR that is installed. You should make sure you have only one version installed because Camera Raw can become confused trying to use a version that may not be current enough to read the RAW files for your particular camera and model. 2. One at a time, go to the two sliders for each of the primary RGB colors. If that color seems too overpowering, drag the Hue slider to the left. If you want it emphasized, drag the slider to the right. You usually want the Hue slider to give you the best compromise between the purity of that primary color and the amount of detail that you can see within it. Figure 4-23 shows the Hue of the Red in this image before and after adjustment. Figure 4-23. From left to right, the image before any Calibrate adjustment and after the change of Hue in Reds, with lowered saturation in reds. Getting and Installing Prebuilt Calibrations The easy way to make sure that your camera's sensor(s) are making accurate interpretations of each of the primary colors is to download a Camera Raw calibration settings file from either your camera's manufacturer orone of these daysfrom the Adobe site. The bad news is that unless you own a very high-end camera, such as a digital back for a medium or large-format camera, you probably won't find such a thing in either place. It's just a matter of time, however. In the meantime, calibration settings are likely to start appearing on enthusiasts' and well- established digital photography sites. Use your Internet search engine. Until manufacturers catch on, you'll have to calibrate your own camera (see "Making situational calibrations" next in this chapter). But wait, there's more bad news: the only way to get truly accurate camera calibration is to calibrate for each camera, lighting, and lens combination that you're likely to use. This works best for a studio (or home studio) situation in which you can easily recreate the same lighting setup. Also, if the setup includes diffusers, reflectors, or backgrounds that may reflect a different light color temperature than the lights themselves, you'll have to calibrate for that shooting combination as well. The "Making situational calibrations" section tells you exactly how to go about making these calibrations. This will also help you set your white balance more quickly and accurately, even if you don't want to save the results as a calibration file. 3. Once you've adjusted the Hue of a given color, use the Saturation slider immediately below to adjust the intensity of the color until you like the combination of what you see. 4. Check the moderately dark shadows, especially, in this case, those cast on the sheet. Are they completely neutral gray? If not, drag the Shadow Tint slider to the right to increase Magenta or to the left to increase Green until the shadow turns neutral. The procedure is the same if the shadows are cast onto colored objects, but it is hard to be as accurate. Since what you're doing at this stage is purely subjective, it's no big deal. If you want to create a calibration for a particular camera and lens combination for use under particular lighting conditions, you must first take a picture in . The chances are particularly good if the lens is a 28mm or wider 35mm equivalent and has not been stopped down more than one or two f-stops. Now, here's the interesting part: you may want. subjective, it's no big deal. If you want to create a calibration for a particular camera and lens combination for use under particular lighting conditions, you must first take a picture in . confused trying to use a version that may not be current enough to read the RAW files for your particular camera and model. 2. One at a time, go to the two sliders for each of the primary RGB