Pros and Cons of using proprietary raw image format
Pros and Cons of using proprietary raw image format | ||
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Depending on your camera model, you can likely choose from two or more different file formats. Three basic types of file formats are offered on compact level digital cameras: .jpg, .tif, or a proprietary 'raw' format. The most frequently used format is the .jpg format, which is a compressed file format. To make the image file smaller, a mathematical algorithm is applied that simplifies the image, thereby making it smaller. Simplifying an image also means that there is some decrease in image-quality. Proprietary 'raw' formats are file formats that are unique to a single vendor, such as Nikon's .nef format, or Canon's .crw format. Both are compressed, 'raw' file formats. Unlike non-raw formats, where an image is taken and the camera processes it to get optimal results, a raw format image file is written to the digital photo storage media as it was captured on the image sensor without any additional processing. The advantage to these raw files is that you can use special software to adjust the original image parameters, such as white balance, contrast, sharpening, saturation, and so on. Because both .nef and .crw file formats have the additional advantage of also being compressed files, they take less storage space than an uncompressed file such as .tif, which is a common uncompressed file format found on digital cameras. On those occasions where you want to maximize image-quality and you have plenty of digital photo storage media space, you should select either a .tif format or a proprietary format if one is available on your digital camera. Besides being compressed, some of the proprietary files use 16-bit images instead of 8-bit images — meaning that they contain much more picture information, which can be useful if you edit the image with an image editor that can work with 16-bit images. The downside of using a proprietary format is that you may need special software to convert the images so that you may view them or use them in other applications. Also, these image files can be very large. So, pick the .jpg format unless you are seeking to get the best possible image-quality that your camera can produce and you plan on and are prepared to use an image editor to edit a .tif or proprietary image file. Be aware that the choice between a .jpg format and an uncompressed format like .tif is a decision between a relatively small file and a much larger file! Image quality can be better but not necessarily significantly better. For example, the same photo of a barn shot with a Canon PowerShot G2 using the 'best' (least compressed) .jpg setting is 1.6MBs. The same image shot in Canon's 'raw' format (.crw) is 3.3MBs; when it's opened up as a 16-bit image, it's a whopping 22.2MBs! If you would like to compare these images, you can find them in the folder /chapter-images/ chap01/02 named barn-jpg1.jpg, barn-RAW.crw, and barn-RAW.tif. The barn-RAW.tif file has already been converted from its .crw format using Canon's RAW Image Converter software. If you don't have software that can read .crw files, you won't be able to open the barn-RAW.crw file. | ||