There are two basic file formats when saving images on the memory card of your digital camera; RAW and JPEG. Yes, some cameras can save images in other formats such as TIFF and DNG but this article is just covering RAW and JPEG formats.
RAW is not really a file format, instead it refers to the file format used by each camera manufacturer where there is minimal in-camera processing of the image data. The camera saves unaltered, or raw, image data plus camera settings for the image such as white balance, sharpness, contrast and saturation. The camera manufacturer usually supplies the software tools required to process their own version of a RAW file with their cameras. There are software suppliers who offer alternatives that promise better, faster or more convenient computer processing of RAW files. Either they can be stand-alone programs or as plug in extras to programs such as Photoshop. The RAW format tends not to be found on basic compact cameras.
JPEG (or jpg) comes from the Joint Photographers Expert Group and is very common storage option for nearly all digital cameras on the market. The camera’s on-board computer takes the RAW data and applies preset image preferences, such as sharpness, saturation and contrast. The processed data is compressed and saved to the memory card as a JPEG file. You choose to use a range of JPEG sizes but the quality of the stored image gets worse the smaller the file. The advantage of smaller image size is that it allows more images on a memory card. The smaller JPEG image files make better use of storage space and are quicker to send over the internet. JPEG is the standard for the display of photographs on web pages, although these are usually smaller more compressed images. The best quality, or least compressed JPEGs do produce very usable images. It is possible to get three to four times as many high quality JPEG images onto a memory card than RAW. This can be an important consideration for any press photographer, who may shoot thousands of images at any shoot. The smaller JPEG file size enables faster transfer and selecting of images to meet editorial deadlines for newspapers and internet news sites. However, for most photographers this won’t be an issue.
When to shoot RAW, when to shoot JPEG?
You shoot RAW when you expect to have to do some post exposure processing. If you’re not sure about exposure or white balance, or if you want to maintain the maximum possible allowable post exposure processing, then you’ll want to shoot RAW files. Some cameras can store a JPEG image along with the RAW file. This is the best of both worlds, you have a JPEG image that you can quickly extract from the file but you also have the RAW data that you can later convert and process if there’s a problem with the JPEG. The disadvantage is, of course, that this takes up even more storage space. Many cameras also store a small thumbnail along with the RAW file that can be read and displayed quickly without having to do a full RAW conversion just to see what’s in the file.
The main reason to shoot JPEG is that you get more shots on a memory card and it’s faster, both in camera and afterwards. If you shoot RAW files, you either have to import them into Lightroom, Bridge, Aperture or similar or you have to then convert them to TIFF, JPEG or PSD on a computer before you can view or print them. If you have hundreds of images, this can take some time. If you know you have the correct exposure and white balance as well as the optimum camera set parameters, then a high quality JPEG will give you a print just as good as one from a converted RAW file, so you may choose to shoot JPEG.
Key Questions To Ask Yourself
If you can’t decide which format to use (RAW or JPEG) ask yourself the following two questions:
- What are your goals as a photographer? The significance of this question is quite important, as you’ll want to select the right file format to match your output goals (print, online display, etc), your technical comfort level, your available storage capacity, your computer software/hardware capabilities and the amount of time you’re willing to commit to the post-production of your work.
- How comfortable are you with editing images on a computer? Many long-time photographers are technically excellent and seldom need to make substantial edits in post-production; while newer photographers out in the digital format may need to employ many post-production editing features available to them to clean up their images. Realistically assessing your technical skill level behind the camera and behind a computer is a key factor in deciding the file format to use.
- RAW is a digital negative holding all the data captured by your camera providing you a foundational element to which to apply all of your edits to with no sacrifice of image quality.
- RAW file software editors allow you to quickly and easily change the output of your image such as adjusting exposure, white balance, noise reduction, image size (interpolation), saturation, contrast, levels, curves, sharpness, output resolution, bits/channel, etc.
- RAW file software editors allow you to load saved adjustment settings and some even enables users to batch process a group of files versus making changes to one file at a time.
- RAW files take up more space on your camera’s storage card than JPEG images.
- Because the RAW file sizes are much larger than JPEG, file storage in camera is much slower, therefore when using motor drive, the number of shots that can be taken is considerably lower than JPEG.
- RAW files require some degree of post processing via photo editing software to convert your image to an editable file type for editing, printing and/or online display.
- RAW file software editors have a learning curve, even if mild, and for the uninitiated can be intimidating.
- Batch processing and/or loading multiple files may tax slower machines and require more computing power to keep your software running smoothly.
- JPEG is a file format that has been adopted as a standard and can be loaded in a variety of programs making display easy and simple.
- JPEG files take up less space on your camera’s storage card than RAW files.
- JPEGs can be loaded easily by most all image editing software applications, requiring no intermediate steps.
- Most cameras enable you to choose what size JPEG files (S, M, or L) to save to your storage card when shooting. This enables you to use smaller images that are easier to handle for email attachments, web display or as an alternate preview mechanism if your camera supports saving files in JPEG and RAW formats simultaneously.
- JPEGs are not a lossless file format. Each time the file is saved, data is compressed, with some data being lost in the process. The net impact can be small loss of colour saturation, colour range and a degree of sharpness. Over time, this can be significant.
- JPEG files reflect a one-time interpretation of your subject based on the settings of your camera (white balance, exposure settings and output resolution, etc.). Altering these settings and re-outputting a new file, as you can with a RAW file, is not possible. What you capture at the taking stage is what you get.
- Interpolating or upsizing an image initially saved as a JPEG can result in less than ideal results. There are some 3rd party software applications that can do this better than others e.g. OnOne’s Resize or Photoshop, but you’re still dependent on using another software application to get the job done.
Which Format Is The Better Format To Use?
For your best shots choose the RAW format and get more details, with minimal in camera processing. This allows greater scope for individual image adjustment on the computer, rather than accepting the preset in-camera adjustments. Also continuing advances in software promises better RAW file processing in the future. Only you can decide which file format to use after matching the pros and cons to your photographic needs and goals. I only ever shoot in RAW not only because I want the highest image quality but the cost of of file storage is relatively inexpensive.