So what's the deal with RAW?

I was 1st introduced to the RAW format when I bought my 1st semi-pro compact, the Panasonic Lumix DMC-LX3 (see my personal review here) . Back then, I had no idea what RAW was all about. But after jumping onto the DSLR bandwagon with the Canon EOS 40D, I slowly grew to love RAW as my standard shooting format over JPEG.

So what is RAW? How does it differ compared to JPEG?

Quote from wikipedia:
"A camera raw image file contains minimally processed data from the image sensor of either a digital camera, image or motion picture film scanner. Raw files are so named because they are not yet processed and therefore are not ready to be used with a bitmap graphics editor or printed. Normally, the image is processed by a raw converter in a wide-gamut internal colorspace where precise adjustments can be made before conversion to a "positive" file format such as TIFF or JPEG for storage, printing, or further manipulation, which often encodes the image in a device-dependent colorspace."

A bit confusing? In lame man terms, RAW, as the name indicates is the unprocessed & uncompressed image coming from the camera's sensor, all stored into 1 big file. It lets you have more creative control over your image during editing basically, and you get a much higher usable dynamic range.

So to make things simple, here is a simple break down of what makes RAW tick....

1) Much greater dynamic range to work with during PP (post processing).
2) No worries on getting the white balance spot on in camera, white balance can be tweaked in PP.
3) Changes done to the RAW file are reversible (because changes are saved in a different *.xmp file), which means the "original photo" is always safe.
4) You have 12-14 bits of color tone data to work with (compared to JPEGs 8-bits).
5) Exposure can be tweaked up to 1 or 2 stops (risks of over or under-exposure minimalized).
6) You have more control over how you wanna process the image (contrast, saturation, hue, noise reduction, sharpening, etc), while JPEG have fixed parameters based on programming/image processor inside the camera.
7) No JPEG compression means no data loss.

As you can see from here, on the right is the JPEG version, on the left is the RAW version of the same shot. Much of the white balance issues can be corrected easily with RAW and highlight clippings are easily recovered.

Sounds good, but then....

1) RAW files are huge (easily 2~4 times more than high quality JPEG).
2) Bigger files means less capacity for your camera & longer write times.
3) Your PP workflow increases at the cost of greater control over IQ (image quality), which means you might spend more time in front of the PC editing your pics rather then shooting photos.
4) You need to install codecs or a 3rd party software like Photoshop to view RAW files (unlike JPEG, where you can view it almost everywhere as long as there is a PC).
5) You need a really fast PC to really benefit from RAW during PP as it takes up a lot of memory.
6) Significantly reduces your camera's burst speed (due to the larger files & longer write times).

Exactly the same shot, but the RAW file is roughly 7 times bigger. 

And so, RAW isn't all that perfect. It has its cons, but for some, the IQ gain out weighs everything else.
Although I have read quite a lot of pros recommending the use of RAW; I have also read my equal share of pros advising against using RAW too often because photography is about spending more time out of the house shooting, not spending hours in front of the PC editing RAW files.

In the end, it is up to the photographer to decide which suits them best.
I for one, like the freedom that RAW provides in PP and I shoot RAW 40% of the time.
Try to mix things up a bit to find your own balance.... =)


Some relevant reading materials on RAW:
http://en.wikipedia.org/wiki/Raw_image_format
http://www.digital-photography-tutorial.com/shooting-raw-vs-shooting-jpeg/
http://www.luminous-landscape.com/essays/rawtruth1.shtml