Before I shot RAW I shot JPEG, and it was easy. What I saw on the back of the camera is what I got back home on my computer screen. A little tightening of the exposure here, a tasteful crop there, and my photos were ready for publication. But there I was on a Plymouth beach witnessing the perfect sunset with my brand new DSLR in hand. It was a tricky exposure. The sky was bright orange, and foreground a range of dark blueish hues. I needed a way to expose it all and because I didn’t know what I was doing I switched my camera to RAW in hopes I would capture everything.

Processing

RAW files and high quality JPEGs produce the same quality photos. The difference is with RAW you get to non destructively tweak your exposure with all of the information your camera captured when the picture was taken. With JPEG your camera decides what is best for your picture and throws away the rest. Unfortunately the flexibility RAW gives you to post process your photos is also its greatest inconvenience. Because RAW files have to be “developed” before they can be shared time must be spent with each and every RAW exposure before it can be delivered to the internet, printer, family, and friends.

Compatibility

Unlike JPEG, RAW is not a file format. RAW is a collection of data that comes straight from your camera’s sensor. It is not only proprietary between camera manufacturers, but between camera models as well. Just because two RAW files share the same file extension doesn’t mean they can both be read by the same application. Just because your RAW files can be read today doesn’t mean software will exist ten years from now that can develop your camera specific RAW files.

File Size

Processing time, and compatibility issues are just some of the baggage RAW brings to the table. RAW photos are larger than the equivalent JPEGs because they contain all the non linearized color values for each of your camera’s millions of sub pixel sized sensors. Instead of saying this pixel is orange and the next pixel is blue a RAW file’s extensive color palette is up to interpretation making a RAW file approximately five times the size of a similar JPEG. This means there is a lot less room for photos on your camera’s memory card when you are shooting RAW.

DNG to the Rescue

DNG is Adobe’s not so secret weapon against the insufficiency’s of RAW. It takes the non destructive editing and file bloat of your basic RAW file and losslessly compresses it into a more universal file format many photo applications can understand. DNG conversion can even include some simple batch processing to make your RAW files ready to be published faster. Best of all Adobe is standing behind DNG the same way they stood behind TIFF with an open specification. That means DNG compatibility is much more likely to be around ten years after your camera’s proprietary RAW files cease to be viewable.

Of course my RAW files from that day on the beach are still viewable, and I managed to pull off a pretty decent shot thanks to the information my camera was able to capture. From that day on I have been converting my photographs to DNG. At first it was because of the compatibility. Nothing would read the RAW files from my brand new DSLR. But the space saving and longevity of DNG makes sense too. I believe in DNG to the extent that I throw away my original RAW files choosing not to embed them in the conversion process. DNG just makes sense. all of the information and non destructive editing of RAW with a emerging compatibility of more standard file formats like JPEG.