Digital Cameras: A Beginner’s Guide to File Formats
December 15th, 2006 • Bookmark on | del.icio.us | Digg It | RedditBY CHRISTINE PEPPLER
For those of you who aren’t computer savvy, buying a digital camera can force the issue of learning a few things about computers if you wish to download, save, or print your pictures at home. Gaining knowledge about file formats is one example. Understanding a little bit about how pictures are recorded on a digital camera and subsequently saved to a computer is critical but fairly simple, even for a beginner.
Digital cameras record images as a grid of pixels. Because the data — the information about the grid of pixels — must be communicated to a computer for downloading, saving, and printing, the format used by the digital camera for storing the data must be understood by the computer as well, regardless of the type of software used by the computer. Thus, there are standardized file formats used, allowing this communication and transfer of data.
There are many file formats, but there are only a few that are the most commonly used with images. Knowing which of these file formats to use when recording and saving images from a digital camera is crucial in assuring good image quality.
• JPG (or JPEG): The JPG file format is the most commonly used for photographs. Most consumer-level digital cameras are set to store images in JPG automatically. The JPG format compresses files to save storage space, but in the process it eliminates some of the data which degrades image quality to a small extent.
Users can adjust the degree of compression/image quality on their digital cameras. However, as degree of compression is reduced and image quality increases, the number of images the camera or memory card is able to store decreases. It is simply a trade-off between image quality and storage capacity.
Choosing the JPG file format is often a good choice for color and grayscale photographs, whether putting images on the Web, viewing them on screen, or producing regular-sized prints.
Users new to digital cameras need to understand that images recorded on the camera can be saved to a computer in the same or a different format. However, an image originally recorded in JPG will never have a better quality than that in which it was originally recorded. Thus, if a user records an image with high compression on their digital camera, they cannot reduce the compression or save it as an uncompressed TIF file on their computer later on, expecting to obtain better image quality.
Each time a JPG file is opened, edited, and resaved, it loses data, and therefore image quality is lost as well. Thus, users should make every attempt to save original copies on their computers so that the image does not become progressively worse with repeated editing.
• TIF (or TIFF): The TIF file format can save images without compression and therefore no loss of image quality. This format can be used with both Macintosh and Windows-based computers. Choosing to use the TIF file format is wise when enlarging images as there is a greater need for high image quality in these situations.
Many digital cameras allow users the option of recording images in TIF format. Although this allows superior image quality, it drastically reduces the number of images that can be stored and is therefore used far less often by the average photographer. However, if a user wants to produce large prints, setting their digital camera to record images in TIF format and saving them on computer in the same manner would be recommended.
• GIF: The GIF file format is used most often for graphics and animation on the Web. It has a limited color palette and is therefore not generally a preferred choice for color photographs, although it does well with black and white images. GIF format images are also somewhat preferred on the Web as their backgrounds can be made transparent and, because of the way they display, can help images load/display more quickly.
Some of the less frequently used formats in saving images include BMP, which produces very large, uncompressed images such as those used with wallpapers; PICT, which is the file format for Macintosh computers; PDF, used by Adobe Acrobat; EPS, FlashPix, and PNG, which are used primarily for graphics; and PSD, which is the Photo Shop format. However, for average folks, recording and saving digital camera images in JPG, TIF, or GIF will meet their needs if they understand the benefits and drawbacks of each and how to adjust accordingly.
Christine Peppler shares information on home entertainment and home electronics products, including digital cameras, on her website, Home Media Store.
Posted in Digital Photography, Equipment |


