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In Lightroom Classic CC 12.2.1 (LR), I've noticed that my images look overexposed and faded compared to viewing them in FastRAWViewer (FRV). Below is an example from FRV:

enter image description here

And here is the same RAW photo imported in LR with no further adjustments made:

enter image description here

  1. Look at the branch pointing in the top right in the background to the left of the main branch. It's visible in the FRV photo, but not in the LR photo due to overexposure
  2. The colors are faded (look at the tone of my skin--in FRV it has a clearly richer color compared to in LR)

Exporting the LR photo as a JPG produces this same exact overexposed image.

Here is the color histogram from FRV:

enter image description here

and from LR:

enter image description here

Viewing the RAW photo in Preview (macOS), exporting it to JPG using Preview, or exporting it using the command line tool sips all produce images that are similar to the FRV photo.

Why is this issue occurring with LR, and how do I resolve it?

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There's no such thing as a "no adjustments" viewable image on a screen from a raw image file. All of the "raw" images you can actually see have had a significant amount of processing applied to them.

In the case of FRV it's probably extracting the camera generated JPEG preview image attached to the raw file and displaying that. So what you're seeing with FRV is the camera's own processing instructions applied. When you open the same file with LR Classic, it seems to be applying its own default automatic processing routine, including auto white balance and auto brightness adjustment, to the image. You can tell LR to apply a different set of default instructions when it first opens a file. The difference between the two images you're seeing is the difference between one set of processing instructions and a different set of processing instructions for the same data set which, if displayed "unprocessed" would look nothing like what you expect the photo you took.

Most raw image files contain enough data to create a near infinite number of interpretations of that data that will fit in an 8-bit jpeg file.¹ Anytime you open a raw file and look at it on your screen, you are not viewing "THE raw file." You are viewing one among countless possible interpretations of the data in the raw file. The raw data itself contains a single (monochrome) brightness value measured by each photosite (a/k/a sensel or pixel well). With Bayer masked camera sensors (the vast majority of color digital cameras use Bayer filters) each pixel well has a color filter in front of it that is either red, green, or blue.² For a more complete discussion of how we get color information out of the single brightness values measured at each pixel well, please see RAW files store 3 colors per pixel, or only one?

How the image you see on your monitor when you open a raw file will look is determined by how the application you used to open the file chose to interpret the raw data in the file to produce a viewable image. Each application has its own set of default parameters that determine how the raw data is processed. Since each application uses a different set of instructions to process the raw information contained in the file, each result will be different.

One of the most significant parameters is how the white balance that is used to convert the raw data is selected. Most applications have many different sets of parameters that can be selected by the user, who is then free to alter individual settings within the set of instructions used to initially interpret the data in the raw file.

¹ Sure, you could take a picture that contains a single pure color within the entire field of view. But most photos contain a wide variation of hues, tints, and brightness levels.

² Except the "red" filter is really more of a yellow-orange color, the "green" filter is more a yellowish-green color, and the "blue" filter is a violet-tinted blue color. In other words, the colors of the filters in a Bayer mask do not correspond to the three colors our RGB monitors emit and blend to reproduce the response in our retinas that many other colors do. In fact, the colors of the filters in a Bayer mask are much closer to the three colors that each of the three types of cones in our retinas are most sensitive to than they are to the three "primary" colors we use for our RGB color reproduction systems.

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  • \$\begingroup\$ Re, "colors of the filters in a Bayer mask are much closer to the three colors that each of the three types of cones in our retinas are most sensitive to..." Which is exactly as it should be. If we want to capture a faithful color image of a scene, we would like the camera to respond to the wavelengths in the scene as closely as possible to how our own eyes would respond to those wavelengths. That's true regardless of whatever technology we ultimately use to reproduce the image on a screen or on paper for our actual eyes to look at. \$\endgroup\$ Apr 25, 2023 at 1:23
  • \$\begingroup\$ @SolomonSlow Except we cheat significantly with the lowest wavelength color filter. Our L-cones are most sensitive to 565nm (lime-green), our "red" filters in our camera's CFAs tend to be most transmissive to 590-595nm (yellow-orange). This allows it to be weaker, which lets more light through and helps overall efficiency. We then compensate for the color inaccuracy when assigning color channel multipliers before converting the whole mess to LaB color space and then transforming it to whatever technology our reproduction devices use (CYMK, RGB, etc.). \$\endgroup\$
    – Michael C
    Apr 25, 2023 at 6:09

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