Prerequisites

Before running the script, you must have photographed the ColorChecker with your digital camera and downloaded the raw file to your computer.

Open the target image in ACR

1. Launch Photoshop and make sure there are no images open.
2. Choose File/Open and navigate to your raw image of the target.
3. Select the raw file and open it. The Camera Raw window should appear.
4. Set the image size to the smallest ACR will support for your camera. (This will speed up AcrCalibrator's processing).
5. Set the color depth to 8 Bits/Channel.
6. Choose White Balance Tool (I), which looks like an eyedropper, and click in the second whitest patch along the bottom row of the ColorChecker. (This gives the script a better starting point to begin its processing).
7. Click the open button. The image should appear in Photoshop.

Mark the corner patches

Select the Pen Tool (P). Note that you must select the Pen Tool and not the Freeform Pen Tool. To toggle between the Freeform Pen Tool and the Pen Tool use Shift-P.

With the Pen Tool selected, click once in the center of each of the four corner patches of the ColorChecker image. This tells the script where to find the patches. Note that you may photograph the ColorChecker in any orientation, but the order in which you click the patches is important. Click the center of each patch in the following order:

1. Dark Skin
2. White
3. Black
4. Bluish Green

It is important at this point that you do not save the image. You must run the script immediately after adding the path with the pen tool. Saving the image will convert its file type from a raw file to some other type (e.g. PSD). This will prevent AcrCalibrator from properly running.

Run the script

From the File/Scripts menu, select the AcrCalibrator option. The script will begin executing and you should observe the following steps:

1. Working on White Balance
2. Working on Gray Patches
3. Working on White Balance (2nd pass)
4. Working on Shadow Tint
5. Working on Green Calibration
6. Working on Blue Calibration
7. Working on Red Calibration
8. Working on Green Calibration (2nd pass)
9. Working on Blue Calibration (2nd pass)
10. Working on Red Calibration (2nd pass)
11. Working on Green Calibration (3rd pass)
12. Working on Blue Calibration (3rd pass)
13. Working on Red Calibration (3rd pass)
14. Done

Save the results

When the script is done, it will report the best settings it found for the ACR calibration controls. It's important to save this information since you will need it when processing your own images. The simplest way is to select the status window, flatten it and save it as a jpeg or gif image.

Refer to the document on using the results for details on what to do next.

How to abort the script

To abort the script prematurely, press the ESC key. It may be necessary to press it repeatedly until the script stops. The script will restore user preferences on exit/abort. Note that if the script crashes abnormally, it may not restore user preferences and you will have to restore them manually. It reports any settings it needs to change when it starts, so take note of them.