In the past two articles, we’ve examined the Adobe Raw camera format, a file format that many cameras offer as an alternate to the common JPEG format.

Selecting camera raw puts you in the driver’s seat when it comes to color conversion and opens up a whole new set of controls that the Adobe engineering staff has thoughtfully provided for us (Figure 1).


  Figure 1

These controls allow us to determine the white point, color balance, size, contrast, sharpness and just about any other variable you can think of — all while retaining the quality of the original image.

 

But once you’ve decided to take advantage of all of the benefits that camera raw provides, one question remains: Do you use a canned or a custom profile? By profile, I am talking about an ICC profile, used to define the characteristics of the camera sensor and lens combination. First, let’s look at the canned option.

Adobe Photoshop installs with not one, but two ICC profiles for each and every supported camera. These profiles are custom-generated for each camera and cover two lighting conditions —  tungsten (2856K) and daylight (6500K). Sliding the temperature slider in the Photoshop camera raw interface will move from one profile to the other or produce an image that is a blend somewhere between the two.

The question is whether this is the best option.
 

Is ICC superior?

Since the production of the first digital camera, discerning professionals have always touted the superiority of using a custom ICC Profile rather than use any canned profile the camera manufacturer supplies.

The truth is that using the profiles that Adobe supplies, in most cases, provides a perfectly acceptable image. You may still need or want to do additional tweaking in Photoshop, but the default profiles can generate a perfectly acceptable product.

Yet the question remains: Can “perfectly acceptable” be improved upon? As with all things color management, the answer is “that depends.”

The less controlled the lighting conditions under which you shoot, the more a custom profile will help improve your image. If you tend to shoot under mostly daylight conditions, you might be perfectly satisfied using the tools Adobe supplies.

But what about those of us that shoot under a variety of conditions, especially mixed lighting conditions such as those encountered at sporting events and many other location assignments?

In those situations, a custom ICC camera profile can help improve things. The problem is in how to produce and incorporate a custom profile into the workflow. 
 

Use a target

First, you will need a target, most often the GretagMacbeth SG Color Checker (see Figure 2) and one of the ICC profiling software packages that supports the target. Yes, this means you’ll need to carry this target with you when you shoot, but the inconvenience is far outweighed by the savings in time when it comes time to process your images.

Figure 2

The process begins by photographing the target under the same lighting conditions as the final subject you will be photographing. Try to get the lighting across the target as even as possible. Even moderately uneven lighting will render the image and resulting profile worthless. Gray or white balance the image as you normally would, photograph the target and then photograph your subject all in the camera raw format.

Since profiling packages do not support camera raw, you will need to use Photoshop to process the image into a TIFF image.  Feel free to use all of the controls in the camera raw application to adjust and correct the image. Process all other images from this session using these same settings. Then, launch your profiling package and use the color checker image to produce a custom ICC profile.

You’re not only producing a profile for your camera, sensor and lens combination, but also this combination under the specific lighting conditions you encountered. This profile may, therefore, have limited use.

Once you have generated your custom ICC profile, use Photoshop to assign it to all of the other images from the session. Viola! Custom corrected images.
 

Is it worth it?

Only you can decide if the time, effort, and expense of the color checker target and profiling software are worth it. If you already own a profiling package you can use the traditional, and much less expensive, GretagMacbeth Color Checker to experiment. If you see much improvement you may want to spring for the more expensive SG target. If not, the Adobe engineers have provided you with all the tools you’ll need and you will save yourself some time and money.

Of course, the above technique is not your only option. Next time, we’ll conclude this series by taking a look at options beyond Photoshop for your image processing.
 

John Nate is a senior color specialist for Chromaticity Inc., an integrator of color technologies for the newspaper and other industries. He can be reached at 616.988.6119 or via e-mail at jnate@chromaticity.com.