The RAW and the cooked
Friday, March 16, 2007
I’ve used digital point and shoots for 9 years - I bought an Olympus when I moved to Manhattan, Kansas and wanted to show the folks back home in England and Ireland what I was up to.
I dropped that camera somewhere in Colorado on the way back from mountain-biking in Crested Butte, and replaced it with a nice sturdy metal-bodied 2.1MP Canon PowerShot S10 when I moved to San Francisco in 2000.
Twinned with a microdrive, it accompanied me as I hiked, mountain-biked and rafted from one side of Costa Rica to the other, and took all the shots on my cycling trips across Europe and down the Mississippi.
So I’ve ended up with a lot of JPGs, and manipulated them a little too. But that had in no way prepared me for how much I’m enjoying shooting in RAW on my new Digital Rebel XT (or 350D).
Firstly, RAW is a lossless format, so you see everything the camera’s sensor picked up (even the highest quality JPGs are compressed, so something’s been thrown away - it’s pre-cooked in the camera, so to speak).
That’s great, but the better trick is that RAW lets you change (without damaging the files) some of the settings that would be written into the JPG, based on your in-camera choices.
Show and Tell
Say you’ve forgotten to change the white balance from tungsten back to daylight when you go out hiking. If you were shooting JPGs, all of them would have a weirdly blue color cast to them, which even Photoshop would struggle to correct.
Here’s a quick example - the original of this shot (shown above) was taken with white balance set to tungsten (because I was taking photographs of the room lit by tungsten bulbs). However, it did it’s job too well - whitening the light too much for my liking.
When you’re under regular lightbulbs, your eyes adjust so you don’t see how yellow it really is - the same effect the camera is trying to achieve. However, when you’re outside looking in at a bulb-lit house, you’ll see the light as more yellow, which is what I was able to do back on the computer with very little effect (and no damage to the image). Here’s what I ended up with - much more what I had in mind.
With RAW, you can adjust the white balance after the fact. Perfect if you’ve botched something up, but also great if you just want to warm something up a little for artistic effect.
The other great easy change is exposure - if you’re shooting in difficult light and aren’t sure you got what you wanted, there’s no need to worry about exposure bracketing or the like. You can wait until you get home and check out the shots on your big screen there.
The file size is much larger than a superfine JPG, but space is cheap these days, both on the camera and the computer, so unless I was really stuck somewhere without any room left on my cards, I’ll keep shooting RAW.