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It is very important that your chart image is opened properly in Photoshop, making sure that no color conversion is performed on the pixels of the image. We recommend that you set Photoshop's Color Settings dialog as shown here:
The rationale behind these recommendations will be discussed later in this User Guide. The primary settings that concern us at the moment are the Profile Mismatches and Missing Profiles items (highlighted in yellow). By checking these checkboxes, you will give yourself the chance to prevent any color conversions when the file is opened — a critically important issue.
When opening the image of your chart, you may or may not be presented with a dialog box, depending on the nature of the image file. Here are the proper responses to any dialogs you may see:
| Dialog Type | Proper Selection |
| Embedded Profile Mismatch | Discard the embedded profile (don't color manage) |
| Missing Profile | Leave as is (don't color manage) |
These responses will guarantee that the pixel values will not be changed in the process of opening the image.
Now you should select the inCamera plug-in from Photoshop's Filters menu:
If you are working with RAW images from your digital camera, they must be converted to RGB before they can be used with inCamera. Photoshop CS can open RAW image files from many digital cameras. You may also use other conversion programs to convert your RAW files into full color RGB files that Photoshop can open directly. The software that came with your camera should do a good job of this.
inCamera will work with converted RAW files, as long as the conversion process is always held constant (i.e. any parameters that control the conversion are fixed). Make note of the settings that you use to convert the chart image that you use to make a profile, and be sure to use the same settings to convert subsequent images that the profile will be used on.
The following guidelines may help you set some of the possible conversion parameters. If you configure your converter to output linear settings (i.e. the RGB values are linear with respect to intensity, or gamma = 1.0), then make sure you output a high-bit image (16-bits per channel). If you configure your converter to produce non-linear settings (e.g. gamma = 2.2), then an 8-bit per channel image is probably sufficient. Make sure the output RGB image does not "hit the wall" in any of the color channels. In other words, you should not have many pixels whose R, G or B values are either 0 or 255. If you have a problem with this, you may be able to specify a different destination profile. For example, sRGB is a smaller working space than Adobe RGB, and so the opportunity for clipping is greater. Adobe RGB (1998) is usually a good choice, since it is larger than sRGB, but not gigantic.
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