Benefits & Drawbacks of shooting in RAW

Benefits


Nearly all digital cameras can process the image from the sensor into a JPEG file using settings for white balance, color saturation, contrast, and sharpness that are either selected automatically or entered by the photographer before taking the picture. Cameras that produce raw files save these settings in the file, but defer the processing. This results in an extra step for the photographer, so raw is normally only used when additional computer processing is intended. However, raw has numerous advantages over JPEG such as:

• Higher image quality. Because all the calculations (such as applying gamma correction, demosaicing, white balance, brightness, contrast, etc...) used to generate pixel values (in RGB format for most images) are performed in one step on the base data, the resultant pixel values will be more accurate and exhibit less posterization.
• Bypassing of undesired steps in the camera's processing, including sharpening and noise reduction
• JPEG images are typically saved using a lossy compression format (though a lossless JPEG compression is now available). Raw formats are typically either uncompressed or use lossless compression, so the maximum amount of image detail is always kept within the raw file.
• Finer control. Raw conversion software allows users to manipulate more parameters (such as lightness, white balance, hue, saturation, etc...) and do so with greater variability. For example, the white point can be set to any value, not just discrete preset values like "daylight" or "incandescent". As well, the user can typically see a preview while adjusting these parameters.
• Camera raw files have 12 or 14 bits of intensity information, not the gamma-compressed 8 bits stored in JPEG files (and typically stored in processed TIFF files); since the data is not yet rendered and clipped to a color space gamut, more precision may be available in highlights, shadows, and saturated colors.
• The color space can be set to whatever is desired.
• Different demosaicing algorithms can be used, not just the one coded into the camera.
• The contents of raw files include more information, and potentially higher quality, than the converted results, in which the rendering parameters are fixed, the color gamut is clipped, and there may be quantization and compression artifacts.
• Large transformations of the data, such as increasing the exposure of a dramatically under-exposed photo, result in less visible artifacts when done from raw data than when done from already rendered image files. Raw data leave more scope for both corrections and artistic manipulations, without resulting in images with visible flaws such as posterization.
• All the changes made on a RAW image file are non-destructive; that is, only the metadata that controls the rendering is changed to make different output versions, leaving the original data unchanged.
• To some extent, RAW photography eliminates the need to use the HDRI technique, allowing a much better control over the mapping of the scene intensity range into the output tonal range, compared to the process of automatically mapping to JPEG or other 8-bit representation.

Drawbacks

• Camera raw files are typically 2–6 times larger than JPEG files. While use of raw formats avoids the compression artifacts inherent in JPEG, fewer images can fit on a given memory card. However, the large sizes and low prices of modern memory cards do mitigate this.
• Most raw formats do not use compression or implement light lossless data compression to reduce the size of the files without affecting image quality. But some others use lossy data compression where quantization and filtering is performed on the image data. Many recent cameras let photographers choose between no compression, lossless compression or lossy compression for their raw images.
• The standard raw image format (ISO 12234-2, TIFF/EP) is not widely accepted. DNG, the potential candidate for a new standard format, has not been adopted by many major camera companies. (See "Standardization" section). Numerous different raw formats are currently in use and new raw formats keep appearing, while others are abandoned.
• Because of the lack of widespread adoption of a standard raw format, more specialized software may be required to open raw files than for standardized formats like JPEG or TIFF.
• The time taken in the image workflow is an important factor when choosing between raw and ready-to-use image formats. With modern photo editing software the additional time needed to process raw images has been greatly reduced but it still requires an extra step in workflow.

Should you use JPEG or RAW?
For most of us, saving in JPEG is more than adequate. JPEG files are compressed and, compared to RAW, they are smaller, save faster, and more images can fit on a memory card. Many professional photographers shoot at the highest JPEG image quality.
For ultimate control over white balance, saturation, contrast and sharpening, and/or if you know ahead of time that you intend to print a certain picture super extra large, RAW file format (or, RAW + JPEG) is the ultimate answer. For many professional photographers, there is no substitute to shooting RAW.