RAW Vs. JPEG
“Cameras don’t take pictures, people do” is a well-known photo adage. However, you not only need a camera to take pictures and to get good exposures, but you need to know what your camera can and can’t do—especially when it comes to setting what image format to shoot with. For this image taken inside of a hot-air balloon (technically called the “envelope” by hot-air balloonists), I shot in the RAW mode rather than JPEG. For me, it’s sometimes a quality and exposure flexibility issue, but more than that, it’s a personal preference. Many photographers think of RAW as a pro mode and that using JPEG is amateur. Some even promote RAW as the only mode to use, which isn’t true. I prefer RAW because it suits how I work and the level of control I want when it comes to editing my images. For others, the extra control may be too time consuming for how they like to work. The benefits it offers me may not be seen as benefits at all for someone else. Both formats are capable of the highest-quality images, and each has its advantages. RAW has a wider range of color and tonality, which offers greater flexibility when it comes to manipulating an exposure. JPEG has more limited flexibility, but doesn’t require conversion in RAW processing—which can be time consuming, especially when you shoot a lot and frequently come home with a couple hundred images. And a JPEG file created by an advanced processor like Canon’s DIGIC chip, for example, is essentially an automated RAW conversion. So, which one is right for you? Image Quality Basically, when it comes to digital image capture, you have two choices: JPEG or RAW. JPEG files are compressed files. All digital cameras nowadays have processors that use advanced algorithms to convert the 12-bit data from the sensor to the 8-bit JPEG data recorded on the memory card. In that process, some information the processor interprets as “redundant” is discarded. When you shoot RAW files, you retain all the data, and you never lose your original file, because you can’t save over it. With JPEG, there’s the danger that you could save over your original file, which will mean your original, captured data would be lost. Some people call a RAW file a digital negative, but that’s not quite true. RAW files are composed of raw data. That data can be processed by a number of RAW-processing programs, and each program processes that data a bit differently, resulting in slight variations. Because of their large size, RAW files take up more room on a memory card and hard drive than JPEG files. Some cameras offer variable settings for RAW image quality or RAW + JPEG, which gives you both the RAW file and a processed version as a JPEG image. Many photographers now shoot in this mode because they get the best of both formats—the increased flexibility of RAW when they need it and the option to work quickly with JPEG files when that suits their needs.
Digital Exposure Basics
Let’s begin with shutter speed. Shutter speed is the time the shutter, which lets light onto the digital image sensor, remains open—or the time the image sensor is activated. If you’re new to photography, look at it this way. If you’re in a room and open and lower a window shade, you’re basically doing the same thing a shutter does: letting light expose an area. The longer you leave the shade up, the longer the room is illuminated. Knowing which speed to choose is the key to getting a desired effect. Sometimes it’s an educated guess. Sometimes it’s just plain luck. But most of the time, it should be the result of knowing how different shutter speeds affect subject movement. Fast shutter speeds “freeze” action, as did a 1/500th second shutter speed when I photographed this horse and rider at the Double JJ Ranch in Rothbury, Mich. The faster the shutter speed, the better chance you have of freezing the action. But there’s more. Telephoto lenses (above 100mm), exaggerate handheld camera shake, as binoculars exaggerate hand movement. So, you need a fast shutter speed to freeze your movement, too. A tripod, other camera support or an Image Stabilization lens can also help reduce camera shake. Tech Info: Canon 1D Mark II, Canon 100-400 IS lens @ 400mm, ISO 400, 1/500th sec. @ ƒ/5.6.