While most pros have decided one way or another on the topic of raw vs. JPEG, these formats of digital photography capture are still a mystery to most amateurs and there's a lot of blind leading the blind out there.
There's no right or wrong answer to which format you should shoot, except what's the most effective for you and best fit for your desired result, but I hope to provide some compelling evidence to shoot raw, at least if you're serious about getting the most out of your camera and digital files.
Did you know JPEG files sacrifice up to 80% of the original captured information, or that the shadow areas in raw files contain more levels of tonal information per pixel than the tonal range of an entire JPEG file?
The science is clear that raw files contain far more information and flexibility than JPEGs, and new software has rendered the old challenges of processing raw completely moot, as now anyone can get the software necessary to manipulate raw files with virtually the same ease as JPEGs.
I suggest you learn as much as you can about each format before you choose. The more you know, the less susceptible you'll be to the rampant myths and misinformation there is about either file type.
To be clear, my focus is mainly on the formats as used in digital capture. What other uses they have are generally not covered, though I touch briefly on formats used for printing.
If you're just shooting snapshots of the kids and sending them to grandma, raw is probably not for you and you don't need to read any further. But if you have any desire to get the most out of your images and the expensive sensor you paid for, you owe it to yourself to explore the differences between raw and JPEG.
Without raw, I could never have developed this image as you see it.
About Raw
Raw is simply an unprocessed proprietary camera file, much like a film negative. It contains all of the information captured from the sensor accompanied by a file containing information about the image that requires a software program, like Adobe Lightroom, to interpret and export to a finished file, much like a lab would process a negative into a print.
This is where the flexibility and power of raw lives, its "rawness" and ability to be processed and developed to your taste -- like a negative -- and not the camera's tastes (like JPEG). The only settings that affect the recorded pixels of a raw image are ISO, shutter speed and aperture, according to Bruce Fraser, author of "Understanding Digital raw Capture" for Adobe.
Non-exposure settings, such as white balance, contrast, saturation, tone curves, color space, noise reduction and sharpening, ride side-car to the original sensor information in the form of an XMP file and are loaded into the raw editor for you to see as a preview. On the camera LCD, they're loaded specifically as a JPEG preview. Processing software, such as Lightroom, enables you to make development adjustments to the side-car information. Changes aren't actually applied until you convert the raw file into something else, like JPEG or TIFF.
To further get a sense of what raw is, recall that in film you can leave a set of instructions with your negatives and have a lab make prints according to those instructions. You can always go back to the negative with different instructions and make a new print because the adjustments affect only the print, not the negative. Light is simply passed through the negative onto the print paper.
The side-car information "stapled" to the raw file is like the set of instructions for how to process a film negative. A program like Lightroom looks at those instructions and renders a preview -- or copy, if you specify -- of the image, but the original file is never touched. In fact, you can never actually edit a raw file. You can only edit the information about it. That means you can keep changing it without affecting the quality of the original file. This helped earn raw the nickname of digital negative.
Is Lightroom the only way to process raw files? No, there are many other programs, including Photoshop, Aperture and CaptureOne.
Another reason raw files are similar to film negatives is because of their tonal range. Raw files contain at least 4,096 levels of tonal information in each pixel. This means a greater range of tonalities to work with. Raw files that are 14-bit contain 16,384 levels. By comparison, JPEG files contain a total of only 256 -- that's right just 256 -- levels of tonal information per pixel, almost no latitude compared to raw.
The greater bit depth of raw means each pixel has more levels of tonal information to play with -- much more. You have the ability to move the negative around -- to bring detail out of bright highlights or deep shadows, for example -- until you achieve just what you want.
One of the most famous photographers ever -- if not the most famous -- is known for his extensive work in developing film negatives in the darkroom, involving clinical filtering, dodging, burning and other techniques used to develop film negatives into prints that helped make photography into a widely-accepted form of fine art. His name is Ansel Adams. It's no leap to imagine that if Adams were alive today and shooting digital, he'd relish if not prefer the information-rich raw files of today's digital cameras over JPEG.
Advantages of Raw
Original file is never degraded. Adjustments simply travel with the raw file and are never directly applied.
Processing settings, such as white balance, sharpness, noise reduction, tonal curves and color space are not applied at capture, so you can change them however you want in post processing. You, not the camera, are in total control over development.
More exposure latitude, meaning you can adjust more stops up and down without significant degradation.
Original file is 12-bit or 14-bit, containing 4,096 to 16,384 tonal values per pixel -- 65,536 for 16-bit files. This means finer detail, especially in highlights, shadows and tonal transitions, and more dynamic range. The shadows in a raw file alone contain as many brightness steps as an entire JPEG image.
Processes just as easily as JPEG with the right software.
Finest image quality worthy of the largest prints.
You can apply camera color profiles that precisely restore and correct colors for a given spectrum of light to any raw file at any time.
Disadvantages of Raw
Requires special software to process and in some cases view.
File is larger.
File takes longer to process in-camera, can be very slow on pocket cameras.
About JPEG
If the sensor is one of the reasons you paid so much for your camera, you might not like the facts about JPEG.
When you take a JPEG photo, rather than retaining all of the information from the sensor, the camera makes certain decisions regarding things like white balance, contrast, even sharpening, then bakes them into the file and discards all of the other data -- about 80 percent of it, according to some calculations. There's not much original sensor information left in a JPEG. The camera then compresses the finished image into a format that almost any computer can read. Every JPEG that comes out of the camera is done: 400 degrees, three hours, dry as a goose, stick a fork in it.
As Fraser put it:
"When you shoot JPEG, you’re trusting the camera’s built-in raw converter to throw away a large amount of the captured data in a way that will hopefully do the image justice. This is exacerbated by the tendency of most camera vendors to impose a fairly steep contrast curve in the raw-to-JPEG conversion in an effort to produce a JPEG that resembles a transparency. In the process, they throw away about a stop of usable dynamic range, and you have essentially no control over what gets discarded." If raw is a digital negative, think of JPEG as a digital slide. The main difference is with digital, raw gives you the ability to further refine sharpness and noise, something not possible with film. If raw is writing in pencil, JPEG is writing in pen. Editing a JPEG is like trying to manipulate a painting that's already dried. A JPEG file that comes out of the camera is already the second generation of the original sensor information, and when you make even the slightest edits to that JPEG in any program, Lightroom or otherwise, the output becomes the third generation. With raw, the first-generation information is retained from camera, and any changes you export from the raw file are only the second generation, and you can make as many second generations as you want from the same raw file.
More JPEG Limitations
If you're thinking the non-destructive editing of Lightroom saves the day, understand that Lightroom makes non-destructive edits only in the sense that what you see is a preview, but when you export the changes, which is necessary for anyone else to see them on say a Web page or print, Lightroom still must render the changes onto an already-processed JPEG that doesn't have nearly the latitude of a raw file.
"JPEGs offer fairly limited editing headroom—large moves to tone and color tend to exaggerate the 8-by-8-pixel blocks that form the foundation of JPEG compression—and while JPEG does a decent job of preserving luminance data, it applies heavy compression to the color data, which can lead to issues with skin tones and gentle gradations when you try to edit the JPEG," says Fraser.
Remember that raw pixels have a lot of depth of information -- thousands of levels. You could "flip through" those levels to bring out just the detail you want. JPEG has 256 levels of tonal information, not thousands. There's a teeny tiny bit of leeway for you to make some edits without highly noticeable degradation, but not much.
JPEG is still a good file, when it's exported from a quality raw file or when it requires almost no post processing. But contrary to what you might think, generally all images require processing to get to a professional standard. When you work with raw, you have to output most images as JPEGs so labs and computers can read them. A JPEG contains enough information to make a fine print. I for one covert all my raw files to JPEG for finished products so they can be displayed on the Web and on clients' computers because JPEG is high quality and portable. But it offers less latitude for processing. I do all my work on the raw file, where I have full flexibility and quality, and then compress into a JPEG.
Advantages of JPEG
Faster processing, since the settings are final and baked in at the moment of capture.
Smaller files for more economical storage.
Requires no processing or conversion to view. This makes it a fast solution for proofing and increases compatibility with devices.
Still has minor development latitude.
Quality worthy of large prints.
Disadvantages
All edits degrade the image in some way.
Discards about 80 percent of the original sensor information.
Image is captured as a final product, with limited development latitude.
Original JPEG file is 8-bit, containing only 256 steps of brightness from white to black, compared to raw's 4,096. This means less available detail in shadows and less dynamic range.
Opmerkingen