Camera Raw

The photos I’ve posted in the last couple of days were shot with a Nikon D70 in raw mode. When a digital camera creates a raw file, it makes a file that is unedited data straight from the sensor chip. (Technically, a few things are done with the file, but it’s basically just sensor data.) The advantage of a raw file is that it is not processed by software in the camera to “optimize” it. A raw file is designed to allow the photographer to process it on a computer using software such as Photoshop. Before such editing, a raw file looks a lot worse than a standard JPEG file that any camera can produce, because it hasn’t gone through software optimization. But a raw file can be more extensively edited than a JPEG. In general, only midrange and professional class cameras can create raw files. Low-end consumer digital cameras generate only JPEG files.

It’s a very good idea, by the way, to convert the raw files your camera creates into a different format—DNG files. DNG is an open format created by Adobe that has several technical advantages over proprietary raw camera formats. Because it’s an open format promulgated by a major company, DNG files will be readable by photo manipulation software 20 or 30 years from now. By comparison, any given proprietary raw format from a specific camera manufacturer may become obsolete in a few years (it’s already happened to some early raw formats). You can get the free Adobe DNG Converter at Adobe’s web site.

Lately I’ve been learning about Camera Raw, which is the program that comes with Adobe Photoshop for working with raw files. The newest version of Photoshop, CS3, comes with Camera Raw version 4. This version has impressive photo editing capabilities all by itself. In fact, it is possible to do all of your photo optimization in Camera Raw, using Photoshop only for certain kinds of tasks. The photos I’ve posted in the last couple of days are edited only in Camera Raw—they haven’t been touched by Photoshop or any other image editor.

I really like Camera Raw’s parametric image editing controls. Particularly excellent features include:

• The ability to recover data from clipped white pixels. When the brightness of a pixel is maxed out in one or two of the three color chanels, Camera Raw can recover usable data from what remains.
• The ability to easily copy parameters from one photo to others. If a group of photos is shot under similar conditions, it’s much faster to edit one photo, copy those edits to other photos, and then tweak them, than it is to edit each photo one at a time in Photoshop.
• All edits done in Camera Raw are non-destructive. That means that none of the original pixel data are modified. You can always go back to the beginning. In Photoshop, you need to work with complex layers to avoid non-destructive edits. In Camera Raw, all changes are recoverable.
• Camera Raw version 4 can now edit JPEG files. You can’t do as much with them as you can with a raw file, but that’s still a useful feature.

Of course, you can’t do everything in Camera Raw. If a file needs masking or pixel-level editing, you need an image editor. But I’ve been amazed at what you can do with what I used to think was just a conversion program. I know this sounds like an advertisement, but it’s really a great program (and I’m not nearly important enough for Adobe to pay me to say that).

Also of interest

• What you can do with an overexposed photo (0)
• Black and white (0)