Most digital cameras record JPG images because the JPG format provides a very high degree of fidelity for photographs in a very small amount of space. JPGs are high quality, small, can be viewed quickly and easily on any computer, and look great when printed. But JPGs, like all image formats, also have some limitations. RAW is another image format that addresses some of JPGs problems. But no format is perfect and RAW images have problems of their own.
I’m about to get all geeky technical but bear with me for about three sentences. JPGs have two major limitations: they only record 8 bits of data per channel (red, green and blue) and all of the camera processing is “baked into” the image at the time it is captured. The number of bits per channel translates directly into the number of tones that are available for each color. JPGs can show 256 distinct tones for each channel. Normally it’s not a problem, but it can lead to posterization in some images. If you’ve ever taken a photo of a sky and seen banding where the transition from one shade of blue to the next was not smooth then you’ve experienced the 8 bit JPG problem.
So what’s that about baking? When you capture an image your camera applies a bunch of adjustments to it from contrast and sharpening to saturation and white balance. It then changes all of those pixels in the image and saves the result as a JPG on your memory card. In doing that, you lose a little latitude in how far you can manipulate the image later in software. You can’t undo the sharpening, for example, if the camera applied too much.
A third issue some people mention is lossy compression but I don’t really consider that a problem. The lossy compression issue is simply this: when you save a JPG, it doesn’t save exactly the same image you opened. To achieve the small file sizes, some of the pixels are changed to allow the image to be compressed and use less disk space. With images like photographs, it’s barely noticeable unless you use a coarse quality setting (most cameras let you choose from several quality levels with the higher quality images using more space). If you open and save the same JPG four or five times to make edits you will begin to see image quality suffer. Solution? Don’t do that. Make all of your edits from an original JPG at one time and save the result as a new file. Want to make more edits? Open the original and repeat. You’ll never be more than one generation from the original and if you save with a high JPG quality setting you’ll never see a difference.
What RAW brings to the table
RAW is an image format (lots of formats actually since every manufacturer’s format is different) that has some advantages over JPG. RAW files record the raw data directly from the image sensor (hence the name) and store it alongside the camera settings. RAW files also record 12 or 16 bits of data per channel, a huge boost over JPG in terms of available tones. Practically this means that you can apply whatever processing you want to the RAW data in post production. Since the camera settings aren’t actually “baked into” each pixel, you can easily readjust sharpness, contrast, saturation and a ton of other settings directly on the source data. RAW files give you a high degree of control over the final output and allow you to perform operations on the highest quality original source data rather than making additional adjustments on top of previous adjustments like you must do with JPG. The upshot is that RAW can lead to a boost in quality in your final output.
In a sense, it’s a lot like working with a digital negative. But that’s also one of the drawbacks of RAW files. They can’t be viewed in their native format without special RAW processing software, the extra data is nice but causes the file sizes to balloon tremendously leaving you with fewer shots per memory card, and each RAW file must be processed and then exported to a JPG format for printing or sharing (each image must be “developed”). It can be a slow and tedious process.
Only bad photographers shoot in RAW. Some people think that only lazy, bad photographers shoot in RAW because it allows them to correct a lot of shooting mistakes after the fact. Some photographers may actually use RAW as a crutch. But the best photographers always try to get everything right when the shutter is pressed. Shooting in RAW is just another tool to help them get the best quality out of their final output.
All pros shoot in format X. The truth is that many professionals shoot in RAW, many shoot in JPG, and many shoot in both depending on circumstances.
Shooting in RAW will improve your photographs. Well, maybe. RAW isn’t going to improve your eye for light or composition. It isn’t going to help you do lighting setups or improve your timing. It will allow you to squeeze every last bit of quality out of every image. But as the saying goes: garbage in, garbage out.
RAW can fix any exposure problems. RAW gives you some latitude in adjusting the exposure after the fact. Because of the extra data, you can get some highlight and shadow detail that would have been lost in a JPG. But changing the brightness of pixels in a RAW image isn’t going to magic additional detail from nothing. A properly exposed image will always look better than one that was improperly exposed and adjusted later.
RAW is better than JPG (or JPG is better than RAW). Each format has its own distinct advantages and disadvantages. There are no absolutes and a lot of it depends on how you like to make photographs. Choose the format that works best for you.
In the end, RAW is just an image format that works well for some people and not for others. It’s a tool that can be used to wring the maximum quality from any image but at the price of additional storage and post processing time. The only way to find out if RAW is right for you is to give it a try.
Is the quality really better?
That’s the million dollar question, isn’t it? When all is said and done and I look at images on my computer screen or hang prints, which format produces the superior result? That is the subject of my next chapter on RAW vs. JPG. Next time, I’ll directly compare scenes shot in RAW and JPG both on a computer screen and in print. A real world head-to-head comparison of the formats to find out if RAW really is worth all the fuss.
Probably one the best, as well as easiest to understand, articles about RAW vs. JPEG. Thank you for sharing. I shoot in both modes. I think it comes down to the particular shooting situation and the intended end-result. If I have a client who is just going to use the images for a website, then it’s JPEG all the way, especially if they are under a tight deadline, which is usually the case.
I always shoot in GIF.
I’m guessing/hoping that carpeicthus means he always shoots in JPEG? I’ve never seen a digicam that used GIF, but maybe some exist???
Anyway, thanks for the solid article.
One advantage to RAW that you didn’t directly mention was that you can create a HDR (high dynamic range) image from a single RAW file, because they have a broader range of tones (channels). So you can split a single RAW image into two or more JPEGs, for example one for the highs and the other for the lows.
I almost always shoot in JPEG unless I’m trying to get every last detail from the image and/or it has a broad range of light to dark and I want to capture the details at both ends of the scale. But aside from trying HDR/DRI, I don’t think I’ve ever liked the RAW that much over the JPEG of the same shot (my camera automatically makes a JPEG when I shoot in RAW).
I hadn’t heard the idea that some photographers use RAW files as a crutch so they don’t have to nail the exposure. It sounds exactly like auto-bracketing the exposure on your shots, though I wonder if the RAW file for a single shot would end up being smaller than three separate JPEG exposures? Hmm, I guess that’d depend on how much the image could be compressed by JPEG?
Very interesting stuff.
Thanks for the practical explanation, as well as the follow-up article comparing their results you plan to write!
I’ve never heard anybody claim that RAW is used as a ‘masking’ for bad photographers.
And from my experience I find that the greater majority of professional photographers shoot RAW over JPEG in almost every ‘normal’ case.
Thanks for the clear and concise article. I did a little bit of poking around on this issue and really like your take on the “Raw vs jpg” debate. Looking forward to the next chapter. Thanks!
I originally started shooting in RAW because I could never remember to set the white balance correctly in certain situations. RAW gave me a second chance at that mistake.
carpeicthus: You obviously have my first digital camera 😉
Just getting to grips with RAW and I’m amazed at what can be achieved. Is it a better format than JPEG? Depends on what you want from your photography!
I’m in the same category as parl above. Since the AWB doesn’t really do the trick, and I often forget to set the correct white balance, I use RAW so that I can choose how to balance the image at my computer.
thanks for the clear and concise article. just wondering how much more space do RAW images take up than JPGs?
I’m very glad that I stop at this site and that I read the article because it has the basic idea of what JGP and RAW are all about. A good shot is a good shot regardless of the outcome for the picture and JPG reduces the amount of options you have with it while RAW creates and opens a wide range of them to make a good picture even better.
Like it is said in the article, the issue with RAW is time the size of the files and the difficulty that you have seeing and processing them but this could be overcome with practice and lots but lots of patience.
I, too, have long considered the benefits of RAW and JPEG. “Better” is always a difficult term because it means different things to different people. RAW is better because it has more information. JPEG is better because it is almost as good and much, much smaller. Which is really “better” depends on what any given individual wants.
I wrote about this on my RAW vs JPEG page on my Landscape Photography blog, too.
Should I shoot in film and scan later or shoot directly onto a sensor? The film will record far more detail (more possible resolution, color and light gradients etc.), and a film scan typically produces more data. Most digital camera sensors do not produce 48 bit images (16 bits per channel) and even when they do, it’s still only three channels (RGB). Scanner sensors more often have the option to produce 48 bit images and because they use linear sensors they can often resolve more pixels for a given image area. The whole process of film and scanning will take quite a bit more work and expense. If I do everything right, I have the potential to create an image better than possible if I were to irreversably automate the workflow in the field.
Essentially, digital, at this point in time, is ALL about automation of workflow and not about potential quality. Because the available quality is more than sufficient for almost anything but a few niche areas (very large prints, ultra high resolution, wide angles of view, landscapes, etc.), the automation of digital is valuable. It makes no sense to go to the trouble and expense of a film workflow to shoot images for newsprint or the web (unless that’s all the photographer knows how to do).
RAW is essentially bypassing some of the automation that digital provides. For most work, it’s not worth it. If it is really worth spending a lot of time working on a single print, RAW can give you more to work with — but it costs storage space, potentially equipment expense, time and attention. If the shot is worth all that, I’d rather have it on film.
I shoot 24 bit jpgs on a Sony camera. I usually run them through Photoshop, but I find that I hardly ever do more than crop or resize them. The Sony camera automatically adjusts the levels, color balance, applies USM, and except in low light produces very little noise. Why shouldn’t it bake the image like this? Those algorithms are well known, simple enough to integrate into the camera, and typically work on most images. With the Sony, tweaking is usually a waste of time and doesn’t produce much improvement because it’s already been done for me. On RAW film scans, I have a lot of work to do.
On the other hand, if I want to capture a once in a lifetime image that I’m sure I’ll do more with than simply keep it on a hard disk archive somewhere, I’m going to shoot film.
But of course, if you want REAL quality, slide film is still the only way to go 😉
Let the flames begin!
Okay, so Raw/Jpg has its own benefits. How about where its processed? maenig what is the different between a JPG created by the camera vs the jpg processed by a desktop PC. i read that because of processing power, its better done on PC. But, whati dont understand is a peace of code that process it is the same on a PC vs Camera. Processing power only enhances spped, not the logic. not the line of code, right? the logic of formatting a bit to a jpg formatted bit should be the same. (excluding mods yo can do to a raw).So shouldnt the out come be the same for JPG proccessed in Camera vs Jpg processed in PC?
It depends on the camera, the software, and the subjective taste of the viewer. You’re right that the same code should produce the same image whether it is run in a camera or on a PC. But cameras are limited in processing power and space for code which necessitates using different (not necessarily worse) approaches for image conversion than what is available in desktop software.
That cleared up a BUNCH of questions I had. Thanks so much for posting this one.
I think the vast majority of photographers shoot in RAW and I don’t believe you should be in JPGs until the absolute final output when it is being prepared for the Web. To avoid using JPG, convert your photographs to TIFFs, not JPGs.