Professional Information Technology-Programming Book part 5 potx

1.8. Final Output The very last stage of processing is to create your invaluable and nearly irreplaceable digital positive. First of all, calling it a negative is technically incorrect and, well, negative. Besides, we've gone well past the point where the image was RAW. You're now making a copy that can be flattened, sized, converted to a more universal format (such as JPEG or TIFF), and assigned the proper color profile for the destination reproduction vehicle. How you create that digital positive (Figure 1-5) will depend on what your purpose is for any given version of a final output file: web, online media, offset printing, or output to a desktop printer. The process may also require switching Color Spaces and Color Management Profiles. We'll cover the ins and outs of all of that in Chapter 12. Figure 1-5. In the end, the goal is a beautiful photograph that can be sent out into the world. Chapter 2. Be Prepared This chapter is about what you need to do to make sure that the pictures you shoot will be of the highest possible quality (given the circumstances you are shooting in at the time). When I start to shoot a job, I want to make certain I think about all the things I can do to ensure that I'm capturing as much of the scene's full dynamic range as circumstances permit, that the pictures will be sharp, and that I am exposing for the most important part of the subject. You may be surprised at how comprehensive that checklist should be. On the other hand, I'm not going to crowd these pages with every esoteric possibility. Photoshop is important, yes, but it works best when it starts with good data. Your Preparation Does Not Start with Photoshop People tend to think of the Photoshop workflow as something that starts in Photoshop. In fact, if you hope to get the best results from Photoshop, the first step in your digital photo-making workflow should be making sure you're prepared. Of course, being completely prepared could entail all manner of complexities. So nope, we're not even going to try that. Instead, this chapter is about making sure you've covered the pre- planning basics. If what you need to do entails more than this chapter covers, chances are you've been in business long enough to know what to do and have an assistant or two who might even know more than you do. If you've been shooting film and are just jumping into digital, you may already know most of what's here. If that's the case, at least read the parts of this chapter that have to do with calibrating your camera and using your camera's Histogram feature. 2.1. Pre-Set Your Camera This section is all about helping you get the most out of the data you create with your camera. If you're shooting JPEGs, you should be doing so because you have no time at all to work on the images before you hand them off to your client. You want to set your camera up so that when it does all the processing, it knows what it's supposed to accomplish in terms of color balance, noise reduction, saturation, sharpening, and even shooting modes such as black and white, sepia, snow, shade, and night shot. NOTE JPEGs are not losslessly compressed, so be sure you always shoot at the highest level of JPEG quality. Remember that each time a JPEG is opened and saved, it is recompressed, so more of your original data is destroyed each time. Consequenbtly, there's actually no such thing as a nondestructive JPEG workflow. If you must shoot JPEGs, at least this book can help you with minimally destructive workflow. If you're shooting RAW, there's no need to use situational adjustment settings, such as cloudy or portrait. The RAW file records everything the camera sees, regardless, and leaves it up to you to adjust things in whatever RAW image processor you choose. So there's no need to waste the camera's energy. Of course, you may want to use those settings if you're shooting simultaneous JPEGs, since the JPEGs will be affected. If you have no control at all over what the next lighting situatio n will be, make sure your ISO is set to 200. If you're shooting after sunset or indoors (or both) make that ISO 800. Then you have a reasonable expectation of getting enough depth-of-field (DOF) or a fast enough shutter speed in a wide range of shooting conditions. What you're doing is making the best compromise between getting a noisier image than you're willing to put up with and having enough "film speed" to get a steady shot in the broadest variety of outdoor daylight shooting situations. If, once you're shooting, you find you have the leeway to drop your ISO setting, you'll have less noise. If you're going to be shooting at night or indoors, take along a flash even if you prefer not to use it most of the time. Instead, take test shots and set your ISO high enough to create a steady hand-held shot. You probably shouldn't worry much about extending DOF unless you can afford a battery-powered external flash system. You'll also want to be able to remove the flash from the camera and, ideally, fire it by infrared remote control. Figure 2-1 shows several portable external flash units. Figure 2-1. External strobes come in a variety of sizes. Plan on using tungsten bulbs if you need to keep your budget down when shooting interiors or in the studio. If you want to have maximum depth of field and the ability to freeze all movement (such as hair blown by a fan), use studio strobes (see Figure 2-2). Battery powered studio strobes cost a bit more but make it possible to use them at locations where there's no easy access to power or where a person is likely to trip over the cords and damage your equipment. Figure 2-2. A typical, reasonably priced studio strobe system. 2.1.1. Set Up Your Camera for What's Most Likely to Happen Next If you miss an important moment because you had to stop and fiddle with your camera, remember that I said this: any time you're about to move from one situation to another and don't know exactly what the upcoming shooting conditions will be, set your camera's mode dial to P, which is short for "Point and Shoot." That is, the camera does the best to automatically figure out the best compromise between shutter speed and aperture. It also assures you that you're going to get a picture. At the very least, you'll be able to look at that picture after you've shot it and be able to figure out whether you need to be able to go to Aperture or Shutter priority or whether you need to switch to entirely manual control. Speaking of manual control, there's one situation where it's always called forwhen shooting with an external flash that's not made specifically to be controlled by the camera. The best clue as to whether your camera can control the flash is whether the brand name on flash and camera are the same. You should also read the instructions for the flash. 2.1.2. Shooting a Calibration Target or Gray Card It's always a good idea to put a gray card in the same position as the subject in at least one frame of any sequence that is shot of the same subject in the same location and lighting conditions. Later, it will be very easy to set your white balance. The best candidate for utility and price is the Digital Gray Card from Robin Myers Imaging. It is made of washable plastic, has full instructions on the back of the card, and comes in two sizes (4x6 and 6x9 at $9.95 and $14.95, respectively). This gray card is 10 percent, rather than the 18 percent gray that is more traditional for film photography, and is said to work much better for calibrating digital sensors. 2.1.3. Get in the Histogram Habit Digital sensors have a greater tendency than film to block highlights. They also have a tendency to exhibit more noise in the shadows. However, don't loose heart. The flexibility you have in interpreting digital imagesespecially RAW filesfar outweighs what you can practically expect from film. Just try to make sure you don't over- or underexpose. NOTE The shape of the histograms will vary greatly from one picture to the next because the shape reflects the distribution of pixels assigned to a given area of brightness. I t only matters that the histogram stops and starts with some space between the endpoint of the histogram and the beginning of "the mountain." You do that by not relying on the camera's preview monitor for checking your exposures. Almost all digital cameras, especially those likely to be used by readers of this book, will let you check the histogram for any image you've shot. If you're shooting with a DSLR, you won't be able to do that until after you've taken the picture. So, as soon as you've put yourself in a position where you're likely to shoot, take a picture. Then look at the Histogram for that picture. You want it to look as much as possible like the Histogram (drawn in Photoshop Elements 4) in Figure 2-3. You do not want the histogram to look like those in Figures 2-4 through 2-7. Figure 2-3. The histogram for a properly exposed image. Figure 2-4. A histogram showing blocked highlights. This is the biggest no-no. Figure 2-5. A histogram showing blocked shadows. Some blocking is OK, as long as the tones that are blocked don't convey important information. For instance, you wouldn't expect to see much detail if looking directly into the sun or at a black velvet curtain. Figure 2-6. Most of the pixels are in the shadows. There are likely to be increased noise levels when the image is properly adjusted because noise tends to reside mostly in the shades below the midtones. Figure 2- 7. Midtones are posterized because they are all the same brightness value. Try lowering the camera's saturation value and/or dropping exposure by one-half stop or so. . has full instructions on the back of the card, and comes in two sizes (4x6 and 6x9 at $9. 95 and $14. 95, respectively). This gray card is 10 percent, rather than the 18 percent gray that is more. is the biggest no-no. Figure 2 -5. A histogram showing blocked shadows. Some blocking is OK, as long as the tones that are blocked don't convey important information. For instance, you wouldn't. circumstances permit, that the pictures will be sharp, and that I am exposing for the most important part of the subject. You may be surprised at how comprehensive that checklist should be. On the