How to use a ColorChecker Passport to create consistently excellent color.
by Sandra Kehoe – April 1st, 2017
I recently watched a video on YouTube where a photographer compared a Canon DSLR against a pair of digital medium format cameras. The Canon images were notably red on the skin tones, which the photographer claimed was well known in the industry, though this is news to me. I rarely comment on such statements, however I felt compelled to point out that any visible color differences were primarily owed to poor profiling and would barely be noticeable if he had used a ColorChecker Passport Photo to set a custom camera profile.
A series of replies ensued and two points became abundantly clear. He really didn’t understand camera profiling, and he mistakenly believed that it had to be time consuming and complicated.
This seems like a good moment to explain the practical usage of a ColorChecker Passport Photo and how it creates a highly efficient workflow with consistently excellent color.
The ColorChecker Passport Photo is a veritable Swiss army knife for the photographer who wants to take control of their color. It is made up of three separate parts that each merit explanation for the sake of clarity.
1) Setting A Custom White Balance
- It reassures clients as images are imported onto the computer if the color balance is already correct.
- The camera data travels with the Raw file, so images already have the correct white balance if supplied to others.
- The preview on the camera LCD is a JPEG and it will be most accurate with a custom white balance.
- It saves time looking for a neutral reference point later in post production.
The above points relate primarily to shooting Raw, but if you shoot Jpeg, it becomes even more important, since tonal changes in post-production are highly destructive in terms of image quality. Always shoot Raw whenever possible, for improved image quality and nondestructive post-production flexibility.
A neutral white balance sets the base color temperature for the scene, so grays lose any color bias, while whites remain clean without hints of magenta or blue for example. The auto white balance facility on your camera is restricted in range and easily fooled, so it cannot be relied on in tricky conditions or where consistency is important with a series of images.
A few seconds spent setting a custom white balance with a ColorChecker Passport can save hours of post-production work and it removes all doubt as images are imported onto your computer looking technically good from the outset. It’s important that the target for setting the white balance has perfect spectral neutrality like the ColorChecker Passport Photo or the whole exercise is pointless. Lower quality alternatives are no good.
The procedure for shooting a custom white balance will vary a little from camera to camera, but in broad terms you simply shoot a single closeup image of the white balance target under the same lighting as the subject and then set that as the custom white balance within the menu settings. The job is done in less than 15 seconds with a positive impact for the remainder of your workflow.
The target image does not have to fill the entire frame and it doesn’t even matter if it’s out of focus with camera shake. All it requires is a well exposed image filling about 2/3rds of the viewfinder screen and the results will be fine.
Once you adopt the habit of regularly setting a custom white balance, you will likely kick yourself for having wasted countless hours in the past. It’s a relief knowing in advance that your images will always start from a neutral position. Any post-production adjustments after this are effectively subjective.
2) Camera Profiling
There is a common myth on the internet that a new profile is required for every subject you shoot if you use a ColorChecker Passport, but nothing could be further from the truth.
The color temperature of daylight can run from cool to warm, depending on the time of day, however this has very little impact on the spectrum of daylight, which remains remarkably stable, throughout winter or summer, from dawn to dusk.
Opinions differ on this point, but based on personal testing, any small differences are not significant enough to have a meaningful impact on the camera profile in my experience. In other words, daylight is daylight, so one profile is enough to cover all forms of daylight with your camera.
Remember that we are not setting the white balance here, which was handled separately by the white balance target. All we are doing is creating a higher quality profile than the standard options found in your Raw processing software like Lightroom, which is where custom profiling works exceptionally well.
We now have the opportunity to establish the correct relative relationship between different colors and you will generally see much more accurate tones. The differences will vary from camera to camera, but I generally see the most noticeable improvements afterwards in blue skies, along with areas of yellow or purple. The image below I shot of some daffodils is a good example.
The software developers do a decent job of creating camera profiles under the circumstances, however they are heavily compromised, since they are expected to work under all lighting conditions from daylight to tungsten or halogen and it doesn’t give the best results. Custom camera profiling fixes this, but it doesn’t have to become a workflow nightmare. On the contrary, it makes editing faster with better results.
The other advantage is that if you are using more than one camera on a shoot, the appearance will be very similar, so if we go back to that initial scenario of working with a medium format camera and a 35mm DSLR, the color will be remarkably consistent and hard to separate. Needless to say those red skin tones mentioned earlier are swept aside.
In my regular work, I have one profile for daylight with each camera and a few others, such as for my studio flash with the beauty dish. If you regularly shoot in daylight mixed with flash you could create a profile for this situation also. In most cases, you can easily apply an existing profile whenever similar lighting is used.
In practice, the only times I need to create a new camera profile with a ColorChecker is under unique mixed lighting conditions. This might be something like the interior of a bar with a mixture of daylight, tungsten and neon where I would absolutely want to create a specific profile.
Creating a custom camera profile is very simple. Just shoot a correctly exposed image of the ColorChecker target in much the same way as I explained for setting the white balance. The ColorChecker Passport Photo software is very smart and can pick out the targets fairly easily. Run the software after selecting the image and save the profile with a name that makes sense to you based on the lighting or location. Then just restart your editing software and the profile will become available. It takes about a minute in total.
A custom white balance together with a custom camera profile will ensure your colors are not only correct, but also consistent across different cameras in a wide range of shooting situations. In a professional context that is a vital competitive advantage.
3) Creative Enhancement Target
The final component of the ColorChecker Passport Photo is the creative enhancement target and this is a more nuanced tool. The first two items are all about technical accuracy, whereas this part is more focussed on creative tweaks in post-production.
To make use of this you would shoot a frame and import it alongside the other images from the same series. The top row is used with hue, saturation and lightness patches to check or edit color shifts in post-production.
With an accurate base from the previous steps this is only something I would only use as an aid for subjective tonal edits. That’s fine because this is specifically intended for adjustments of this kind, but in a way that is controlled and realistic.
The middle rows are useful for warming up skin tones or making grass appear greener. This would be something you might do for aesthetic reasons and the process is very easy. You would simply sample the patches with the White Balance Selector and apply the change as a batch setting to the other images once you are happy.
This is something I use less often, but if your model would benefit from a more tanned appearance for example this can be used to obtain a realistic result. We are naturally attuned to the way we expect skin tones to look, so using these creative patches can help you produce a result that doesn’t appear artificial.
The bottom row contains a line of targets ranging from black through to white that can be used in post-production to evaluate shadow details or highlights by enabling the tone clipping warning.
Here are some key benefits of the creative enhancement target:
- Create your own repeatable look.
- 1-Click enhancement for any workflow.
- Add warmth to skin tones or boost tones in landscapes.
- Extend the power of your editing software.
- Judge, control and edit images for shadow details, highlight clipping or color shifts.
Note: The creative enhancement target and classic color target can still be useful with Jpegs, however it’s an uphill struggle because Jpegs are very prone to damage from post-production manipulation, so the key lesson is to stick with Raw files and reap the rewards.
Ashley Karyl is a UK based Commerical, Fashion, Nature & Celebrity Photographer and an X-Rite Coloratti Pro
He is the Author of “Colour Management Pro” https://colourmanagementpro.com