PicaJet Blog

The Low-Down on RAW Digital Photo Files – In Simple Terms!

My students are often confused by the file options (RAW or JPEG) in their cameras. Without going into huge detail, I generally suggest my students opt for a medium to high JPEG file because the majority of my students have no interest in adjusting their digital images at a later time. 

  

But if you want more control over your images, you might want to opt for RAW files…read on…

 

RAW or JPEG — what’s the difference?   

RAW photo files, like a raw carrot, await a brilliant cook/artist to do something to them.  But, unlike a raw carrot which can be perfect as is, pictures printed from RAW photo files can be much better after manipulation—RAW files are meant to be adjusted before being saved as JPEG prints.

 

Years ago, before the advent of digital cameras, a film photographer had to visit the processing bath in his darkroom before being able to show off his photographs; that’s where he’d turn his negatives into prints.  In this sense, RAW files are similar to old-fashioned film negatives–that’s “similar” because unlike old film negatives, a RAW file can be printed without manipulation.

Jim McGee, with Vividlight.com, writes, “It’s important to understand that a print of the raw file without any changes will look identical to a high resolution JPEG file captured at the same time. What you’re getting with a RAW file is the ability to make changes later on.”

In fact, when shooting in RAW, your camera will totally ignore any previous settings you might have opted for like a particular white balance, color saturation level, or decreased resolution.

So, what’s a JPEG file?   

JPEG (Joint Photo Experts Group) is a computer formula that digital cameras use to compress RAW information into smaller more manageable files.  But as this data compression or processing takes place, some digital information must be sacrificed (lossy compression).  Setting a camera’s “picture quality” setting and/or “resolution” will determine how drastically information is cut from each image.

In addition, every single time a JPEG file is manipulated, or saved, information is lost leading to a lack of sharpness.  This doesn’t happen to a RAW image file because it remains in it original state.  And remember, too, unlike a RAW image, once a JPEG image is created, the information lost—can never be regained. 

The good news, however, is that JPEG files, while reducing file size, have the uncanny ability to maintain the visual quality of an image, in spite of dumping excess information.

What can a photographer do with RAW images?  

RAW digital image files allow the photographer to later tweak his images in his digital darkroom, using the largely unprocessed information (a little processing does take place in the camera) saved to the memory card during shooting.  A photographer can set a different white balance, he can adjust his exposure compensation by a couple of stops, and he can adjust the image’s finer points like sharpness, contrast, and color saturation.  In short, he can alter his photograph’s “original” data to an adjusted JPEG image, ready for printing.

Why would a photographer choose RAW over JPEG? 

In a word, or two—it’s creative control.  When shooting in RAW, a photographer reserves the right to “fix” his images long after the fact (post-processing), something that can’t be done as efficiently on a compressed and processed JPEG image.

And no matter what, a photographer will always have the option to return to his RAW digital images, months or even years later, and adjust them to his heart’s delight.

What are the drawbacks of choosing RAW over JPEG? 

The biggest drawback is a loss of speed as the camera processes digital images to its memory card.  Fast action shots will be impeded by opting for RAW files.

Also, you’ll need to invest in larger memory cards; uncompressed RAW files use massive amounts of memory per image.

In addition, depending upon your computer’s processor speed, the huge RAW files can cause your computer to freeze up.  I did this once on a photo shoot in New York City.  I was breaking in a new Olympus eVolt 300, and had shot in both JPEG and RAW.  My older laptop couldn’t bear the processing burden and resorted to the blue screen of death.  I was barely able to recover my files upon returning home.  But the lesson was learned–I bought a new laptop with a bigger and faster dual processor.

Note:  You may see RAW files referred to as NEF by Nikon, as CRW by Canon.  Also, you simply cannot fix a poorly-taken photograph.  An out-of-focus image will remain out-of-focus since camera shake is recorded regardless of whether the camera is saving in RAW or JPEG.  So, in low light situations, use a tripod.

 

And another note:  “RAW” isn’t short for anything.  It should actually be written, “raw.”  But I’ve capitalized it throughout this blog, just because I like it capitalized–looks better that way.  IMHO

 

Cheers,
Sheree Zielke

This entry was posted on Wednesday, November 7th, 2007 at 5:56 pm and is filed under Digital Cameras, Photography tips. You can follow any responses to this entry through the RSS 2.0 feed. Responses are currently closed, but you can trackback from your own site.