Digital Camera Storage Choices

As I mentioned in an earlier blog, I have moved to digital photography after many, many years of using film. It is a big change in so many ways and I am still learning the fine points.

One of the most important things about digital photography is the image types that are available to you. Using a film camera, I had to first choose between black and white film, color negative film, or color slide film. When I chose one of the three, I had to choose among many choices for each type of film; i.e. Kodak Ektachrome, Fuji Sensia, Fuji Provia, etc. (these being a few of the choices in color slide film). Each had their specific qualities and idiosyncrasies.

In digital photography, you don’t choose film type. Rather, you choose the image type you wish to use to store your images (there are other choices you must make like ISO speed, but we will talk about that in the future). In digital photography, your basic three choices of image types are: JPEG (JPG), TIFF (TIF), and RAW.

In lesser expensive digital cameras, you don’t have a choice: there is only JPG. As you move up in price and quality, one or both of the other two types will also become available in the camera. Each has their advantages and disadvantages. Here is a quick, down-and-dirty look at each type.

JPEG – The biggest advantage of JPEG is that it is a very small file sizes, therefore you can store more images inside the camera. And most cameras give you a choice as to what size of an image you wish to shoot (i.e. 640x480, 1024x768, 2560x1920, etc.).

JPEG is also the default type used on the Internet, making it much easier to share photos among friends and family.

The disadvantages of JPEG are many. Primarily, in order to make the file size so small, much of the information contained in an image is discarded and the remaining data is compressed. While it may not be obvious in most pictures that pixel data is missing, you will become aware of it if you do post-processing of a JPEG image in software such as Photoshop, Elements, Paint Shop Pro, PhotoImpact, or any other image processing software.

You see, if you make any kind of changes to an image and save it, the software will try to recompress the JPEG image again, throwing out more image information. So the more times you save it, the more of the image is lost each time. So, if you must work on your images to make them better, do all the work before saving it so that you do only one additional save.

TIFF – This is probably the best way to save an image. Unlike JPEG, you can save a TIFF many times and never loose a pixel. I do almost all my post-processing work in TIFF. When I scan my slides into the computer, I always saved them as a TIFF. It is arguably the best way to save images when doing post-processing.

The disadvantage of TIFF is that it is probably the largest size of all image types. For instance, using my 8-megapixel camera as an example, setting it for the largest, highest quality, lowest compression JPEG image file, the file size would be 6.1 Mb. Using TIFF, the same size image would be 23.3 Mb, almost four times larger. If you decrease the size of your JPG image, the size difference will become even greater. This file size affects how many images you can store in your camera’s memory card before it becomes full.

So, while TIFF may be the best quality image-of-choice, you shouldn’t use it unless you have a huge capacity memory card in your camera, or you use it only on selected pictures at the time you take them.

RAW – This is the most interesting of the three file types. A RAW image isn’t so much an image type as it is a way to store original, unprocessed data. Even more interesting (and maybe confusing) is that RAW differs between each camera manufacturer. An Olympus RAW file is totally different than a Nikon RAW file or a Canon RAW file, unlike JPEG or TIFF, which is the same for all cameras.

The best way to understand RAW is to compare it to a piece of film that hasn’t been developed yet. The first thing I must do when processing the RAW image in Photoshop is “develop” the image. If I like the original exposure, I may develop it exactly as-is. If it is slightly underexposed or overexposed, I can play with it until I achieve the right exposure. Then I can adjust the white balance, sharpness, saturation, contrast, brightness, shadow detail, and more. In other words, I can make the “perfect picture” long after I have taken it with the camera.

After adjusting all these details, I then develop and save the image as a TIFF or any file type I choose in my computer and continue with post-processing. For a professional or serious amateur photographer, using RAW only makes good sense. And RAW is definitely my image type of choice, since I post-process all of my photos, usually in Photoshop.

The disadvantage of RAW is that it requires more work on your part and the file size is still fairly large. But it is a lot smaller than TIFF. Using the same example I gave above, a TIFF in my camera is 23.3 Mb., while the same size RAW image in only 13.3 Mb. As I use mostly a 1Gb memory card, I can store 72 RAW images in my camera before having to change cards. That is a lot, compares to the number of images I could get on a roll of film.

One other choice that I have with my camera is that I can also set it to take a RAW image and a JPEG image at the same time. I also have the choice of which size JPEG I want to shoot with the RAW image. If I am shooting a wedding for instance, I will set the camera take both a RAW image and a 640x480 JPEG image at the same time. I will use the smaller JPEG images for proofs for the customer, then process the RAW image for high quality larger prints for the images they eventually choose.

I hope this not-so-short explanation of image types has been of help, whether you have a digital camera already or are contemplating buying one in the future. If you have questions, just drop me an e-mail and I will do my best to answer you.