Steve Broback defends the JPEG format, providing tips on adjusting optimal settings.
Today, much debate surrounds the two main file formats that digital photographers have at their disposal. Serious photographers are hearing from various camps about the respective advantages of JPEG and RAW, resulting in a lot of confusion.
I have been following this debate closely for some time, and have been asked by several photographers for guidance regarding which format they should be using. The answer depends largely on what kind of photos you are shooting, how much control you need to have, and how much time and disk space you have.
For those unclear on the difference between shooting RAW and shooting JPEG, a RAW file essentially is a saved version of the unedited data that comes straight off a camera’s CCD sensors when an image is captured. To use a simplified film-based analogy, a RAW file is akin to having a digital negative, whereas a JPEG is better thought of as a digital version of a finished print.
RAW is an excellent format for photographers who insist on maximum data integrity, but it results in very large files and significant post-processing time. JPEG is a file format that offers significant compression options, but also can provide outstanding image quality.
If you’re a pack rat like me, and hate to throw things away that you “might need someday,” RAW is for you. Because you end up saving every little tidbit of image information that the camera could grab, it ensures that you can always create the best possible finished files.
Another great thing about the RAW format is that it allows for a terrific amount of control. Because so much image information is captured with RAW, the user has the ability to make broad tonal adjustments without losing much detail or introducing much noise. The ability to recover highlight and shadow details from an image is a compelling reason for shooting RAW files.
As one may guess, capturing and keeping this raw, unaltered data results in some very large file sizes. Also, RAW files are largely unfinished, as they have not had proper “de-mosaicing” of the CCD capture, white-balance adjustments, tonal corrections or other settings applied. That means that photographers must prepare and convert these files to another format (usually JPEG) in order for the end user to take advantage of them. This conversion requires launching and using special software on your PC or Mac, which can be time-consuming and requires an extra level of expertise to operate.
Dozens of programs are available to help photographers make these conversions in their computers and customize them to maximize the quality of images. Popular applications include Photoshop with Camera Raw, CaptureOne, Nikon Capture and iPhoto, to name a few.
Consideration of JPEG settings will enable you to get much of both worlds: optimal quality, but fast workflow.
Because a finished print is what your best photos are destined to become, it’s nice to let your camera do the work, which is where JPEG comes in.
Using fast, chip-based processors, digital cameras create JPEGs when they convert initial CCD captures on the fly to make them more manageable. In a nutshell, a JPEG is a RAW file that has been tonally adjusted, sharpened, compressed and reduced to eight bits (just 256 tones vs. several thousand for RAW) per channel, and has had white-balance settings applied. The good news is that you get a finished file very quickly at a small size; the bad news is that some data is lost in this translation.
Despite the insistence of some vocal evangelists, RAW is not a format that everyone should feel compelled to use. When these purists say that RAW is the only way to shoot, consider the following advantages that the JPEG format offers:
• Size - JPEG primarily reduces file sizes by removing data that it sees as redundant, so shooting high-quality JPEGs allows the storage of two to three times the number of images on a memory card, compared to RAW.
• Shooting speed - These smaller files display and process faster, which allows more shots to be taken consecutively. Better to have grabbed the shot you wanted, with a bit less data, than a shot you didn’t want, at full quality.
• Workflow speed - JPEG files transfer faster from memory card to your hard drive, and allow you to open the files directly in Photoshop without having to convert them. This is one reason that newspaper photojournalists and other pros tend to shoot JPEG.
Although it is true that RAW allows for increased editing of image files without creating detectable artifacts, it cannot perform miracles. A RAW file only holds what the sensor has captured; if the exposure is beyond the range of the sensor, both formats will be at a loss to display data that just isn’t there to start with.
Also, many photo gurus agree that if you have good control over the lighting in which your shots are taking place, and if the images do not need to be printed at sizes above 8x10, the advantages of RAW largely evaporate.
Optimal JPEG settings
Even low-end cameras permit photographers to adjust which settings are applied to their JPEGs when they shoot them. Common adjustments include resolution settings, sharpening amounts and compression settings. JPEG is a so-called “lossy” (as opposed to “lossless”) compression format, so the more compression you apply, the more damage the image experiences. Careful consideration and adjustment of these settings will enable you to get much of both worlds: optimal quality but fast workflow and smaller files.
Whatever you do, don’t just run with the default JPEG settings that the camera manufacturer has set up. In virtually all cases, those settings will bludgeon your images with small but unnecessary modifications that, in effect, damage pictures.
Not so many years ago, I advised photographers to assess the resolution that they typically needed, and to target their captures to match that desired size. The thinking was that, if your images are headed for newsprint at small sizes, why store many megabytes/gigabytes of image data that never will be needed during printing?
I have since amended that recommendation to take into consideration the realities of the modern world. These include media cards and hard drives that are cheap and huge now, and modern computers that can burn multi-gigabyte DVDs.
If you dwell in this high-tech world, here is the more up-to-date approach: use the highest-quality settings that your camera offers, both in JPEG choices and resolution. This will result in slightly larger file sizes, although they’ll still be far smaller than RAW files.
No matter what world you live in, minimize or eliminate in-camera sharpening. Sharpening is one of the actions that cameras perform on your photos during JPEG conversion. Although it’s intended to make the photos look better to the eye, it actually amounts to damage that accentuates edges and tricks the eye into thinking that the photo has been improved. Some experts may advocate sharpening, but the one-size-fits-all attempt made by most cameras is inappropriate and is best done later in Photoshop to the specific settings that relate to output. Find your in-camera sharpening setting and set it to “off,” or at least to “low.”
A little of both?
Several of the latest digital SLRs can shoot both RAW and JPEG at the same time, providing some of the advantages of both formats. The main disadvantage is that this method creates additional files and uses up a lot more card and drive space.
So, which should you use: RAW or JPEG? There is no simple answer, because all photographers have different needs. Landscape and fine-art photographers, for example, often choose RAW in order to maximize their image quality, while the advantages of JPEG are clear for sports and press photographers.
The long-term picture is that media and processing technologies will continue to improve and drop in price. That implies that the inconveniences of RAW will become less and less noticeable over time. If your camera can save to RAW quickly, and your computer can rapidly convert images to JPEG for you, RAW will become the preferred format. Thank heavens for the progress of digital technology, as we pack rats can hold more and more information that we “may need someday.”