Understanding RAW Format
All digital cameras take their original image in some kind of RAW format. RAW files are usually proprietary to the camera manufacturer and sometimes to the specific model of camera. That means, only the camera that takes the picture can understand the information collected on the camera sensors. That information is then translated by means of firmware (software) built into the camera and the usual result is a more user friendly format called JPEG. That is why most cameras produce images with an .jpg extension. JPEG is a compressed format (and has the ability of varying degrees of compression). JPEG has become a fairly universal digital standard for photo images. The one big advantage of JPEG is that it takes less storage space than the original RAW file. What happens is that all digital cameras use firmware to apply various qualities to the RAW format before it is translated and written to the memory card in JPEG form. The firmware in the camera will apply varying degrees of sharpening, varying degrees of saturation, varying degrees of contrast, etc. Most cameras have facilities to change these settings to the photographers liking. The only hint you have of what that photo will look like is the small LCD on your camera. This is usually too small to tell enough to make changes until it is too late. Often the photographer doesn't want to mess with those changes on the field anyway. So you set your camera based on the last experience. Many people never experiment with changing these settings anyway.
The Advantages of RAW format (Menu)
Thus enters the advantage of shooting RAW. The RAW information settings can be set in the software after you get the image home or downloaded to your computer where you can see the image on your large computer screen before you develop it into JPEG. There are three RAW software publishers (which I discuss below). Two of which I use and I'm sure there must be others of which I am unaware. Many digital cameras still do not give you access to the RAW format so JPEG is your only choice. These are usually the point and shoot digital cameras. But for those of you who have RAW available and would like to experiment with the versatility of RAW format may want to give consideration to the following information.
RAW conversion Software (Menu)
Today there are serval publishers of RAW conversion software. Most of them will do an excellent job. Here are three of my favorite. Adobe Lightroom and Adobe Photoshop CS5 and now CS6 (the latest version) reads RAW format for most late model digital cameras. Phase One publishes RAW format conversion software called Capture One (http://www.phaseone.com). Another publisher who continually upgrades their software is called Bibble. You can download a trial versions of most publishers software. I found this to be quite helpful in making my choice. For several years I used Capture One for its workflow ability over Adobe Photoshop and Bibble. In recent years Adobe Lightroom has become my favorite choice for RAW development with its slide show and web production features and it's excellent ability to edit local areas of an image. There are also many publishers who publish plug-in software for Adobe products which further enhance the power of these products. And at the time of this update I am aware that there are many RAW conversion publishers now producing softare. Some are even free. Recognize that the free sofware will not have the convenient features of the more expensive software.
All of these publishers have become quite profecient in the addition of features that add a lot of advantages to shooting in RAW format. One of the most used features is the ability to adjust exposures and apply sharpness and saturation settings to a selected area of your photograph, making High Dynamic Range (HDR) photographs much easier to produce.
All of the software packages allow you to adjust exposure settings by plus or minus two stops or more. This can be one of the biggest advantages of shooting RAW. You can make adjustments, as slight as it may need, as if you were doing it in your camera at the time of exposure. (Although I do recommend an accurate exposure at the time of shooting. That will still result in the best detail. Adding or subtracting exposure to an inappropriately exposed image will still result in lost detail.)
Also you can adjust settings for saturation, contrast, sharpness, white balance, etc. just like the settings in your camera would have done, but now you can adjust it as many ways and as many times as you want for each picture and see what's happening with each adjustment before it is developed.
For me one of the wonderful features of RAW and perhaps the one that makes the biggest difference is the ability to correct white balance in post processing - once white balance is set in the JPEG you are stuck with it. You can make slight changes with color balance in Photoshop but post processing white balance is so much more effective with its RAW digital format. Digital cameras have the wonderful ability (unlike film) to change white balance with every shot. See my article on UNDERSTANDING WHITE BALANCE. A RAW file might be considered similar to a film negative with adjustments.
Disadvantages of RAW format (Menu)
One big disadvantage of RAW files: they are large and take up 2 to 4 or more times the space of JPEG files, depending on the compression choice you use in JPEG. So keep in mind your storage space when making a decision to use RAW. When making a choice to use RAW files there are three other things to consider. Number one: RAW files cannot be saved back to RAW once they are converted to JPEG. The advantage of that is your original RAW file is never changed nor is any information lost in compression because you cannot re-save to the original file. So your original information is always left intact.
I understand that every time you load, edit, and save over an original JPEG file it is further compressed each time you repeat that process.
If you loaded, edited, re-saved, and closed a Jpeg file in Adobe Photoshop and repeated that process a 100 times you would see considerable degradation in the resulting Jpeg file. (The solution to that dilemma is to always rename your file so you do not save over the original JPEG if you are not shooting in RAW.)
The second advantage: If you need to save space you can always delete your RAW files after you have arrived at your best settings and converted to JPEG. Personally I like to choose my best shots and keep the best RAW files and save over my JPEGs. If the JPEG gets degraded I can always go back to the original RAW file and develop again from the original information. (However keeping my RAWs may mean buying larger and multiple hard drives. I now have 14 one terabyte hard drive each over half full. Seven are my originals and 7 of them are backups.)
Number three: It takes considerably more time to develop RAW files than to have the JPEG already finished out of the camera. It took my son quite awhile to see the advantages of RAW solely based on this fact alone. It is just too much trouble for some people. For me it lends versatility and allows further creativity in my photography.
Number four: RAW images without any qualities applied tend to be flat and dull. So there is a learning curve in the software area that sometimes intimidates the less techy person. But if you like to be your own artists in the photography category you will like shooting in RAW format.
I do not in anyway pretend to be an expert in RAW file development but I am sharing my personal experiences over the past ten years or so. Since the day I bought my first Canon SLR (10D) I have rarely (and then only accidentally) shot in straight JPEG. (I have shot 100's of thousands of images since then and have developed most of them from RAW.)
What format is best? (Menu)
There are professionals who shoot in RAW. There are professionals who shoot in JPEG and both do wonderful work. It is somewhat a matter of your preference, your time, your space, and your desire or need to have the extra flexibility of RAW format. My son shoots and works for Michael Shaffer Photography (http://www.schafferphotography.com/) and they still shoot most of their work in JPEG.
I am the amateur hobbyist professional who desires take the extra time to work with RAW. I don't have deadlines to meet with my photography most of the time. Sometimes there is the need to have that shot just perfect. I've found that RAW format has been a big advantage at getting just the right lighting, exposure, sharpness, saturation, and white balance, for my landscape and nature photography without the loss of any post-processing detail. I like RAW format a lot.
At one time if I needed to get a large batch of photos ready quickly, I would set the software to batch develop all the photos at the camera settings, go have lunch and when I came back they would all be developed. Then I would come back and redo pictures that needed more attention. But after several years of experience and the evolution of software capabilities I am now more selective in which pictrures I actually take time to develop.
I hope this is helpful. These examples were converted by the use of PHASE ONE Capture One RAW conversion software. The only manipulation performed on these two photos in Photoshop was sizing. Nothing else was manipulated outside of PHASE ONE Capture One RAW conversion software.