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90 ADOBE ® PHOTOSHOP ® FORUNDERWATER PHOTOGRAPHERS Above—Original digital camera image of feather duster worms in the Cayman Islands. Left—The Layers menu shows the Background image at the bottom, High Pass filter in the middle, and the Dust & Scratches layer at the top. LAYER CONTROLS No matter which method you use to sharpen your image—the Unsharp Mask, Smart Sharpen, High Pass filter, or maybe a third-party plug-in (see chapter 15)—you should always apply the sharpening effect to a copy (Ctrl/ Cmd+J) of the Background layer. You can then use the Opacity slider to increase or decrease the effect by controlling how much the original, underlying Background layer shows through the duplicated later. You can also use more than a dozen different blending modes on your sharpening layer. Before you scan through the different layer blending modes, make sure you have the Move tool selected from the toolbox. You can then hold the Shift key and use the + or – keys to move up and down through the layer blending modes. You can also use either the numeric keypad or the Opacity slider to change the opacity percentage. Add a Mask. You can also add a mask to your sharpening layer, and then use the black brush to selectively remove the sharpening effect. By adjusting the opacity setting of the brush, you can control the sharpening removal. The blending mode and opacity setting for the Brush tool are found at the top of the editing screen. ADVANCED SHARPENING TECHNIQUES 91 Top—Enlarged section before any layer edit- ing is added. Center—Enlarged section after the High Pass layer was added. Note that the backscatter in the background was unaffect- ed by the High Pass filter because of the mask, and the resulting image is unacceptable. Bottom—The water background was copied and pasted as a new layer. Then the Dust & Scratches filter was applied to remove the backscatter. A s the digital camera became the norm, photographers—especially those using DSLRs—were introduced to the RAW file format. Initially, most manufacturers had their own RAW translator and editor specifically designed for their camera models. If you owned several cameras, you had to open a different program for each camera’s type of RAW file. With the introduction of CS and CS2, it all changed, as the RAW file interface in Photoshop can now accept dozens of different RAW file formats. The key to working with these RAW files is to remember that they are just that—raw data. The file has not been adjusted by the camera for contrast, sharpness, white balance, gamma, and many other camera settings. All that must be done in the RAW file editor. When you load a RAW file, the editor automatically loads along with the file. Most of image controls are located under tabs for image adjustment, sharpness, noise, lens corrections, gamma curve, and sensor calibration. A DJUST TAB The best place to start your image adjustment is with the Adjust tab. Here you have the option to select from more than a half dozen different white balances, so you can pick the one that best fits the image. We recommend that you use As Shot for your starting point. The Exposure, Shadows, Brightness, and Con- trast are set to Auto in the installed default mode, but you can adjust them if necessary. Just move the sliders and the Auto box is unchecked so that you can adjust the settings. There are additional sliders for Saturation, Tint, and Temp- erature, so you can manually bias the white balance. We just told you to use the Auto function to correct your images in the As Shot white balance mode, but sometimes it can cause problems. Yes, it will automatically correct your images—quickly and easily—but it may not provide a true representation of what your camera’s LCD viewer recorded. For in- 92 ADOBE ® PHOTOSHOP ® FORUNDERWATER PHOTOGRAPHERS 9. WORKING WITH RAW FILES THE KEY TO WORKING WITH THESE RAW FILES IS TO REMEMBER THAT THEY ARE JUST THAT—RAW DATA. WORKING WITH RAW FILES 93 The Camera RAW editor can be opened from Bridge, Photoshop, or by double clicking on the files in the operating system’s File Manager. Camera RAW is divided into three areas: the tool- box at the top, the workflow in the lower-left corner, and the image adjustments on the right of the screen. The toolbox and the adjust folder will be used to make most of the corrections to your RAW files. 94 ADOBE ® PHOTOSHOP ® FORUNDERWATER PHOTOGRAPHERS These images illustrate a problem with digital camera exposure. The top image looks good but is actually being corrected 3 stops by the RAW file editor. If you turn off the auto exposure in the RAW file editor as shown in the bottom image, you will see the actual exposure made with the camera. If you are getting these kinds of settings, you need to adjust your digital camera exposures so that the auto exposure is closer to 0. stance, if the Auto Exposure indicates +3, you should note that your camera exposure is way off. Turn the Auto functions off initially to see just how your camera is recording the exposure. To maximize your editing capability, you must begin with a good exposure. A correct exposure should be relatively close to zero when you check the Auto boxes. D ETAIL TAB The two most important features under the Detail tab are the Sharpness and Color Noise Reduction sliders. The Sharpness setting is pretty straightforward with one slider that adjusts the sharpness from minimum to maximum. Move WORKING WITH RAW FILES 95 Another method for reducing blown-out areas in the RAW file image is to manually reduce the exposure. As you do, you will notice that those areas indicated in red will slowly disappear. 96 ADOBE ® PHOTOSHOP ® FORUNDERWATER PHOTOGRAPHERS The White Balance tool was applied to a gray area on the scuba tank (top) to correct this avail- able light image. The resulting image (above) shows a big improvement. your cursor over the large preview image and use the Ctrl/Cmd and +/– keys to zoom in and out on the image. When you zoom in, hold down just the Ctrl/Cmd key and the cursor turns into a hand, allowing you to reposition the image. The Luminance Smoothing and Color Noise Reduction sliders are then used to reduce any artifacts that occur due to the sharpening effect. L ENS TAB If you are shooting underwater images using a wide-angle lens, you may have vignetting due to light falloff. To correct this, select the Lens tab, and move the Vignetting slider labeled Amount to the right until the lighting is more even. If your image shows some chromatic aberrations (color fringing along sharp edges), you can use the sliders labeled Fix Red/Cyan Fringe and Fix Blue/Yellow Fringe to make your corrections. The Midpoint slider at the bottom of the menu is used to adjust the midpoint corrections in the upper sliders. C URVE TAB The Curve tab displays the actual photographic curve captured by the camera. If you want to adjust the ratio of tones in the shadows to highlights, you can select any of the existing points on the curve or add new ones. You can then move the selected point, and the image will reflect the changes you made to WORKING WITH RAW FILES 97 You should check the Highlight and Shadow boxes at the top of the Camera RAW editing screen to see shadow and highlight areas that are being clipped and losing detail. In this case, a highlight was blown out, so the Curves folder was selected and the top of the curve was pulled down until the bloom- ing disappeared. the photographic curve. A histogram of the data is displayed behind the curve to help you determine how to make your image adjustments. C ALIBRATE TAB The Calibrate tab features sliders for adjusting the color settings of the camera profile used to take the RAW file. With these sliders, you can adjust the hue and saturation for the red, green, and blue channels in the image. There is also a slider that can be used to adjust the shadow tint. If you like the changes you have made, you can save them as a new profile to be used on future images. This is an extremely powerful tool for color crossover problems. W ORKFLOW OPTIONS The Workflow Options menu can be found in the lower-left portion of the RAW file editor. With this menu, you can set the color management profile of the image, bit depth (8 or 16/Bits Channel), and the resolution of the image. The Size control allows you to change the actual megapixel rating of the image from less than 2 megapixels to over 25. If you know that you are going to need a larger file size for printing, this is the place to rescale the image. Also, if you know your image will need a lot of sharpening, you might consider increasing the file’s megapixel rating because the higher the resolu- tion, the more you can sharpen the image. 98 ADOBE ® PHOTOSHOP ® FORUNDERWATER PHOTOGRAPHERS This image is extremely off color because the flash was either too weak or too far from the subject. The image was first cropped with the Crop tool in the toolbox. The White Balance tool was then used to select a small white coral in the lower-left portion of the image. The adjusted image was then import- ed into Photoshopfor final cleanup of backscatter and other small artifacts. TOOLBOX The RAW file toolbox is located at the top of the editor and provides power- ful control over your RAW images. Working from left to right, you have the Zoom tool for zooming in and out on the image, and the Hand tool for mov- ing around in the image. The third icon, the White Balance tool, is probably one of the most power- ful tools in the RAW editor. When you click on something that should be neu- WORKING WITH RAW FILES 99 This RAW file fisheye im- age of the Wreck of the Anne (right) in the Solo- mon Islands proved to be dark, bluish, and lacking color saturation. The im- age was easily corrected by clicking on a sandy area using the White Balance tool. No other correction was made to the image. [...]... ready to try your hand at shooting the ultimate underwater RAW file image, a 360-degree underwater panorama Four RAW file images were shot using a fisheye lens and were edited in Camera RAW using the same settings for all the images 102 ADOBEPHOTOSHOPFORUNDERWATER PHOTOGRAPHERS 10 ADVANCED BACKSCATTER REMOVAL O ne of the most difficult aspects of underwater photography is backscatter It varies... layer is from the same RAW file, but the underwater portion has been corrected The mask was added to block the sky in the top layer so the sky from the background could show through Facing Page—The final split-level image was saved as a PSD file so that we could adjust the topside and underwater portions separately at a later time 100 ADOBEPHOTOSHOPFORUNDERWATER PHOTOGRAPHERS The solution is to... This second pass should give you a nice texture and tonal value that looks very natural If you don’t like the idea of switching back and forth between the Clone and Healing Brush, set the Mode (top of the editing screen) for the Healing Brush 118 ADOBEPHOTOSHOPFORUNDERWATER PHOTOGRAPHERS Top Left—This digital camera image of Fijian soft coral has blown-out highlights and several patches of dead coral... selection, and the Filter>Noise>Dust & Scratches filter was applied Finally, a new Levels Adjustment Layer was added to the statue group of layers where we adjusted for correct color, brightness, and gamma levels 110 ADOBE PHOTOSHOPFOR UNDERWATER PHOTOGRAPHERS Top—The Select>Color Range command was used to select the water background so that a new layer could be created from that selection Above—The... amounts of noise to equalize the editing effect 112 ADOBE PHOTOSHOPFOR UNDERWATER PHOTOGRAPHERS Top—This digital camera image taken in the Solomon Islands has both large and small backscatter particles The Spot Healing Brush was used to remove the large particles Bottom—The Polygonal Lasso tool was used to select the backscatter in the background before the Filter>Blur>Surface Blur filter was applied... background noise in the selected and unselected areas match 114 ADOBE PHOTOSHOPFOR UNDERWATER PHOTOGRAPHERS 11 REMOVING UNWANTED OBJECTS A s your editing skills improve, you will be anxious to tackle more complicated problems Be aware that the editing problems often increase exponentially with the size of the area you need to edit! Decades ago when underwater photographers were struggling with new film technologies,... shows the enlarged selection around the sensor artifacts to be repaired The middle image shows the default settings of the Dust & Scratches filter before it is applied, and the bottom image reflects the effects of the applied filter 108 ADOBE PHOTOSHOPFOR UNDERWATER PHOTOGRAPHERS DSLR SENSOR ARTIFACTS DSLR camera sensors can be exposed to the environment, especially when you change lenses When this... it reappears, and back off slightly until it disappears again ADVANCED BACKSCATTER REMOVAL 105 When you use a flash to light fire coral from behind, backscatter usually becomes apparent 106 ADOBE PHOTOSHOPFOR UNDERWATER PHOTOGRAPHERS Top Left—Here’s an enlarged section of the area to be fixed Above—The Magic Wand and Lasso tools were used to select the background area with the backscatter problem... in the camera RAW editor and bring it into Photoshop as your background image Then, reload the file and make changes with RAW file control to correct the underwater portion of the image Open this image in Photoshop, then copy and paste it into the background image Press the F7 key to open the Layers palette, and add a mask to the layer with the corrected underwater portion Take the Brush tool set to... times have since gone by the wayside, as we now work to put reef survival before our passion forunderwater photography This presents a dilemma Film images can last more than 50 years and often contain great content that may not easily be replicated Do we use these photos as they are, or do we make them politically correct in Photoshop? In FILM IMAGES CAN LAST MORE THAN 50 YEARS our first book we suggested . bring into Photoshop. A good example of this is a split- level image where you have a good exposure above water but a dark and off- color underwater area. 100 ADOBE ® PHOTOSHOP ® FOR UNDERWATER. may not provide a true representation of what your camera’s LCD viewer recorded. For in- 92 ADOBE ® PHOTOSHOP ® FOR UNDERWATER PHOTOGRAPHERS 9. WORKING WITH RAW FILES THE KEY TO WORKING WITH THESE RAW. the problem. 102 ADOBE ® PHOTOSHOP ® FOR UNDERWATER PHOTOGRAPHERS When you have mastered RAW file shooting and editing, you may be ready to try your hand at shooting the ultimate underwater RAW