Switching from film to digital capture requires a whole new look at one's photographic knowledge. I used to create an image by using light to excite the silver halide crystals on a cellulose film. There were certain films I like better than others. Now I capture 1's and 0's on a digital sensor and store the images on a memory card.
If you look at your QUALITY menu you see some letters that really have no meaning other than in photography. These are options of different types of files. Your image can be recorded on your memory card in any of these file formats. You might think of this as using one type of film on some images and then switching to another for some other shots. As with anything there are better types of files for one application and others for another application. It also has to do with how much time you want to spend doctoring up an image and what you want the quality of that image to be.
HERE ARE SOME EXAMPLES OF DIFFERENT FILE TYPES THAT CAN BE RECORDED ON YOUR MEMORY CARD
Basic point and shoot cameras may have less options and very expensive DSLR's may have a few more.
JPEG fine
JPEG normal
JPEG basic
TIFF 8 bit
TIFF 16 bit
RAW
DNG
RAW +JPEG fine
RAW+JPEG normal
RAW + JPEG basic
When selecting these formats the camera will record a RAW fine and a JPEG file at the same time
To make sense of what these different files mean I will give the PROS and CONS of each:
JPEG (Joint Photographic Experts Group)
Advantages: Jpeg files are the most widely used format for photography. Camera software can quickly process these files and file size is quite manageable allowing many images to be stored on a memory card. They are read by all modern image programs so they are the most acceptable format for web sharing, and printing, either through online photo image sites or with photo ink jet printers. To create a jpeg file the camera processes the image for size, tone, color balance, saturation, contrast, sharpness, etc. based on the user settings. Minimal post processing is required and image quality is usually excellent on the initial file.
Disadvantages: Jpeg file format is a compressed format and, by definition, are lossy. Because of the algorithms used to compress this file, image quality degrades each time it is opened or closed. The greater the compression the greater the image quality loss. Every jpeg file has image errors no matter how little it is compressed. (Jpeg files are 8 bit files and have 256 levels of information for each channel whereas 16 bit files have 65,536 levels per channel.) More on that some other time. Because of the lower levels of information image quality is easily degraded when post processed in Photoshop. Jpeg files also work best with continuous tone images. High edge contrast may cause posterization in any post production. Jpeg format should not be used for archiving images. Jpeg images should be converted to a lossless file format (Tiff) or burned on CD as soon as possible to prevent any image quality loss.
TIFF (Tagged Image File Format)
Advantages: Tiff files are not compressed so they are lossless. No image quality is lost when the image is opened or closed. Tiff files are also processed by the camera for tone, color balance, saturation, contrast, sharpness, etc. like jpeg files. Tiff images can be either 16 bit or 8 bit files. Image quality is usually excellent on the initial file and will not degrade in time. It is the most widely used format for archiving images. 16 bit tiff files hold up very well to post processing.
Disadvantages Tiff files are often ten times larger than the same resolution jpeg file. Because the files are so large, camera processing and writing to memory is often very time consuming and rapid shooting is not possible except on high end cameras. Fewer tiff files fit on a memory card and higher RAM is needed to process images on processing programs. Not all older image software can open tiff files. Tiff files must be converted to jpeg files to upload on the web and they may also have to be converted to be printed.
RAW
Advantages: Only raw image data is recorded on this file format and no camera processing is done to the file. This format is the choice of those who want the most control of the image processing and have the software and knowledge to do it. Because no image processing is done in camera file sizes are more manageable than tiff files and rapid shooting is possible. Raw converters allow major image changes with no degradation to the image quality. The raw files does not change and any processing is recorded on a separate file so you can always return to the original data if a different processing is wished. Raw files retain structure better than other files when processed and the finest quality image can be obtained.
Disadvantages: Because no in camera processing is done, raw images initially look poorer in quality than tiff or jpeg images. Images must be processed by image software in order have acceptable quality. Much time is required to properly process each image and processing software is expensive and often too complex to casual users. Many types of image software cannot open raw files because each camera manufacturer has their own raw file specific to their cameras. As new cameras come out older software may not be able to open their new raw files.
Adobe DNG (Digital Negative)
Adobe is addressing the lack of an open standard for raw files by introducing the raw digital negative (DNG). Camera manufacturers use different raw file formats which are specific to their cameras. Photo processing programs must have different software to open and support these files. Photoshop has over 200 different raw converters to support different raw files. Some cameras manufacturers have adapted the DNG file format which assures universal transfer of these files across different software. Adobe provides the free Adobe DNG Converter which easily translates raw files from many of today’s popular cameras. Go to Adobe.com/products/dng/ for a free download. Also, write your camera manufacturer and encourage them to use Adobe's DNG as their raw file format. I did this after I found my old Photoshop program would not support the Raw file of my new camera. Now I convert all my raw files to DNG's so I will always be able to open them in Photoshop.
Now you have some idea what these different files are and depending on how and what you shoot you will know which format to use.
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