When I was a film photographer, I shot both print film and slide film made by different manufacturers with different ASA ratings. The difference among all these films is something that they also shared in common. Each rendered light differently, in a consistent manner. This allowed the photographer to select the right film for the job.
In the world of 35mm digital photography the camera’s sensor is not user changeable. This means that the quality and color captured in our images is limited by how the sensor records light. There are various methods of defining this and I won’t be discussing them at this time.
Professional Photographers, enthusiasts and serious amateurs all want to capture the best possible image. The best way to start that process is to set a custom white balance before a photo session and to set a new custom white balance each time the light changes. This can be a subtle as clouds developing in a cloud free sky to a change of location such as outdoors to indoors. When you are indoors, the light you are photographing under makes a difference in your custom white balance so it is necessary to recognize the type of lighting and set your custom white balance accordingly.
Some of you may be thinking to yourself, “why would I want to do that? I can adjust my white balance during post processing?” This is true, but adds a step to processing that you shouldn’t have to deal with. In fact, setting a custom white balance ensures that you have a consistent starting point for post processing your photos. This becomes even more important if you like to use actions and presets for processing. You cannot get a consistent output without having a consistent input.
The correct way to set a custom white balance is to follow the instructions in your user manual, but my manual (Canon) tells me to shoot a white piece of paper and set the CWB using that image. It is simple to do, but fails to take into consideration that white paper is seldom pure white. Most often it has brighteners that impart a color cast. This is where a calibrated custom white balance tool, such as a WhiBal or Ed Pierce’s Digital Calibration target, provide a consistently accurate white balance. If you are going to set a custom white balance, why not make sure it is accurate?
Earlier I mentioned that the quality and color captured in our images is limited by how the sensor records light. This raises another question. Why bother setting a custom white balance if no two brands and models of digital cameras record the light identically? The answer to this lays in a product produced by X-Rite, the X-Rite Passport Colorchecker. This handy tool allows you to build a custom camera calibration profile for each lighting and camera body/lens combination you encounter. A camera calibration profile adjusts the colors your camera’s sensor recorded to exactly match the calibrated colors of the passport colorchecker. It’s fairly simple to use, you just have to remember to use it. First you set a custom white balance using the white balance tool of your choice, then you take a photo of the passport colorchecker. It’s that simple. Each time your change your CWB, take another photo of the passport colorchecker.
Once your shoot is over and you’ve downloaded the images for processing, it’s time to create a camera calibration profile. If you’re using Lightroom, you select the image of the passport colorchecker and then go to “File – Export with Preset – X-Rite Presets – Colorchecker Passport. When the Lightroom plug-in is done, it will ask you to name the calibration profile. If it tells you that it cannot create a profile, don’t worry, all is not lost. You just have to take a few more steps. Export the file as a DNG file and launch the standalone Colorchecker Passport software. Follow the software instructions. Once the software is through processing, give the profile a suitable name, such as 1DmkIV HS Gym, 1DsmkIII 85 1.2L my studio, etc.
No matter how you post process your photos, you will now be starting from the same point each time, allowing you to use your actions and presets with consistent results.
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