Why use RAW?

For nearly ten years I had digital cameras that were capable of putting out RAW image files, but I never used the feature. Why? Probably an intimidating lack of understanding and the impression that the process was too complicated for my use. Granted, ten years ago the software for RAW conversion and processing was not near as user friendly and powerful as it is today.  But we fear the things we don’t completely understand and I thought JPEG compressed and pre-processed images were good enough for me.

Little did I know the possibilities that the RAW format opens up.  Now I wish I had taken some of my older pictures as RAW images. Why? Well, I used to work in a camera shop and run a photo mini-lab. I also took photography classes and learned how to develop film and prints by hand.  I could put the same negative into that mini-lab ten times, with ten different settings, and get ten prints that all looked slightly different.  Same negative, just different output from it. The negative never changed.

That’s how I relate to RAW and JPEG.  The RAW image file is my negative.  I can make adjustments and spit out a JPEG image with the adjustments applied.  The JPEG image is like a print. Sort of.  You can still make adjustments to a JPEG image, but it’s already been processed and saved in a compressed format, so you don’t have as much latitude and flexibility. If you edit and save a JPEG too many times it starts to show compression artifacts (jaggies or graininess).  Many cameras do a great job of exposing, adjusting, and processing a JPEG image so only slight adjustments are necessary, and this is why I thought I could get by shooting JPEGs for so long.  But a JPEG has already had sharpening, white balance, contrast, and other adjustments added and “finalized” by the camera. These things cannot be undone. You can only add more adjustments on top of the ones saved in the original file.  And saving that second set of adjustments re-compresses the image file and you lose some quality (unless you “Save As” and create a copy).

RAW isn’t really “raw” data from the camera’s sensor. After all, the camera’s computer has interpreted the raw data and created the photo you see on your camera’s digital screen, so there is some processing going on. But no compressing is done and no major adjustments are automatically added. The cool thing is, RAW files are much more flexible when you start working with them on the computer. This last weekend I took my five-year-old son hiking and ran into a good example of where RAW really shines. Take a look at this photo:


What you are seeing here is one of the toughest lighting conditions you can throw at a camera meter. God truly made our eyes wonderful things, and man’s technology still has a long ways to go. The meter was fooled by the bright, direct sunlight and nearly all details of the surrounding beach were lost in black shadows. Or were they?  Take a look at the same photo after some quick highlight and shadow adjustments were applied to the entire scene using Apple Aperture:


I still wanted the semi-silhouette effect, so I kept my adjustments minimal, but I could have made the sand even lighter. Amazing, isn’t it, that all that detail was hidden under those black shadows? Ah, the beauty of RAW flexibility! Pay particular attention to the dark areas of sand, and the details in the clouds along the top of the photo. Both shadows and highlights now show detail that was not in the first image. If I had shot this as a JPEG image, there would have been little I could have done to save it. But just think what I could do with this shot if I half-way knew what I was doing!  Oh well, when I learn more later, I can just grab the original RAW file and apply adjustments from scratch again.

For those of you who are curious about the equipment and settings here they are:

Canon EOS 50D with Canon EF 17-40mm f/4L at 19mm.  ISO 100, f/11, and 1/320.


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