Digital SLR Superguide: Using a dSLR
The meat on RAW
A word on RAW--the RAW file format offered by dSLR cameras is probably one of the most compelling reasons to get one. A RAW file is the digital equivalent of a digital negative. It allows you to fine-tune the exposure of your images (up to +/- 2EV either way), adjust your white balance settings, and set the saturation and hue settings without altering the original--unlike JPEG or TIFF formats where these settings are locked in at the time of shooting.
Put simply: The RAW format is much more flexible and you get all this and more at a file size that’s typically smaller than a full-size equivalent TIFF file. The RAW format will be discussed in greater detail later (Part 4) in our Workflow section.
Most digital cameras feature an automatic white balance mode where the camera processor looks at the overall color of the image and calculates the best-fit white balance. However, like all technology, this is not foolproof. The measurements can often be slightly out especially if the scene is dominated by one color, or if there is no natural white present in the scene.
Having fun with white balance
Using white balance settings can be a source of creative effects for your pictures. For example, if you’re taking a landscape image of a beach and you want to make the light warmer to create a sunset effect, try setting white balance to Fluorescent. This would effectively tell the camera that the light is too cool. The camera responds by shifting every color toward the warm, red values. Dial in a Tungsten white balance, and the camera shifts all colors toward the cool, blue values, producing a "sunrise" effect.
Obviously, there would be a lot of trial and error involved, but the good thing about digital is that you’re free to experiment and review the results at very low cost.
The other alternative to getting perfect white balance every time is to capture your images in the RAW file format. When you save an image in RAW file format, you are saving it the way the image sensor sees it--without applying any adjustments (including white balance) to it. In fact, the camera ignores any white balance values entered except as a default setting. In the post-processing phase, using an image-editing software with the appropriate RAW plug-in, you can load the RAW image to JPEG, and apply any white balance values you wish, until you obtain the perfect color balance.
|
Using a dSLR
