Friday, July 18, 2008

Photography tips: shooting in RAW

Not too long ago, memory capacity shortage was a big issue on consumer cameras. The following quote is less than two years old: “The easiest way to sound like a professional when you talk about photography these days is to grumble about the deficiencies of RAW file converters. The ability to save pictures in RAW format rather than JPEG or TIFF is what distinguishes a "pro level" camera from a consumer device.” Consumers used the JPEG file-format, since it is much more efficient and requires a lot less space. These days are gone however (and I even wonder if they were still there in 2006), as all dSLRs and an increasing number of smaller cameras have the ability to store whatever their sensor picks up in the RAW-format.

RAW means just that, raw. It is not an abbreviation; it refers to the uncooked nature of the data. For those interested in all the technical stuff that can be said about RAW-files, please refer to the wiki link provided below. I am not into technicalities, I care only for practical use.

Oh no! What have I done?
Recognize that? Post processing a large number of pics, getting into routine mode and finding out a little too late that that single precious picture should have been processed a tad different? No problem if your workflow is right, but what if you do this while taking the picture? Still had your white balance set to ‘cloudy’? Was your exposure correction still set to –1? No problem if you shoot in RAW. The great thing about using RAW is that it stores all the data that the sensor picks up. It does have its limits –a burnt highlight is a burnt highlight, detail that is not there, can not be stored- but its limits are much wider than that of a jpeg-file, leaving you far more room to compensate for your own stupidity during shooting.

Once you use RAW, you’ll start counting on it. I never bother to check the white balance on my camera, as it can simply be restored. I mostly use a grey card while shooting, but I have to say that Photoshop often does a great job at automatic conversions from RAW. True, white balance can be altered in any file type, but it works better with RAW-files, since all the data are there. This way, the quality loss is smaller (or even zero) than in the case of, say, a jpeg file.

If a pic is underexposed, you can save it in post processing at the cost of substantial noise. The same thing can be done in RAW, but at lower noise levels and with greater recovered detail in the dark areas. No wonder RAW files are far more suited for High Dynamic Range (HDR) applications. Most modern HDR-software even allows for HDR files from one single RAW-file. Try that with a jpeg-file!

The bottom line is that RAW files can help you save some of your result if you made a mistake or if the situation did not allow you to take a perfect picture. If your camera allows you to shoot RAW-files, start doing it now. If your camera doesn’t, take that ability into account when deciding on your next camera.

More resources

Wiki on RAW


Correcting your white balance using a grey card

Tutorial for a HDR-picture from 1 RAW-file

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