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I have two pictures taken today with my Nikon ZFC MILC + Nikkor Z 50mm 1.8S lens. The photos were shot in the morning at around 7:30, it was cloudy and raining slightly (you can see the water drops on the leaves). They were shot within two minutes and there were no changes in light conditions. They were taken from the same place and the target is the same tree. The second picture target is slightly to the right and about 4 feet farther.

Why isn't the first picture green like the second one?

EDIT ADD: I have three pictures of the first target and three for the second farther target. They have the similar color as in the attached pictures.

first picture

File:           DSC_1188.JPG,
Date Created:   17-05-2024 07:31:07,
Date Modified:  17-05-2024 07:31:07,
File Size:      7.63 MB,
Image Size:     L (5568 x 3712), DX,
Image Quality:  Jpeg Fine (8-bit),
Device:         Nikon Z fc,
Lens:           NIKKOR Z 50mm f/1.8 S,
Focal Length:   50mm,
Focus Mode:     AF-A,
AF-Area Mode:   Wide-area AF (S),
Aperture:       f/2,
Shutter Speed:  1/800s (Auto),
Exposure Mode:  Aperture Priority,
Exposure Comp.: 0EV,
Metering:       Matrix,
ISO Sensitivity:ISO 200,
White Balance:  Auto1, 0, 0 (7750K),
Color Space:    sRGB.

second picture

File:           DSC_1189.JPG,
Date Created:   17-05-2024 07:32:47,
Date Modified:  17-05-2024 07:32:47,
File Size:      8.70 MB,
Image Size:     L (5568 x 3712), DX,
Image Quality:  Jpeg Fine (8-bit),
Device:         Nikon Z fc,
Lens:           NIKKOR Z 50mm f/1.8 S,
Focal Length:   50mm,
Focus Mode:     AF-A,
AF-Area Mode:   Wide-area AF (S),
Aperture:       f/2,
Shutter Speed:  1/400s (Auto),
Exposure Mode:  Aperture Priority,
Exposure Comp.: 0EV,
Metering:       Matrix,
ISO Sensitivity:ISO 200,
White Balance:  Auto1, 0, 0 (4650K),
Color Space:    sRGB.
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    \$\begingroup\$ Take a look: photo.stackexchange.com/questions/61491/… \$\endgroup\$
    – Rafael
    Commented May 17 at 18:35
  • \$\begingroup\$ 1: White Balance: Auto1, 0, 0 (7750K), 2: White Balance: Auto1, 0, 0 (4650K), Unless there's something white in the scene white balance is either going to not work, or resort to auto-levels. So the results can be a little random in exceptional circumstances. \$\endgroup\$
    – davolfman
    Commented May 20 at 20:31

4 Answers 4

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The camera's metering system and auto white balance system are basically a database of many shooting scenarios, and the camera tries to "guess" what you are shooting and how you want it to appear. If you move the camera, and, for example, there is more sky in one photo than another, or more dark areas, or more bright areas, or more green than blue, or more blue than green, etc, etc, then the camera may decide that you want a different look.

If you want precise control of the colour captured by the camera in these situations, you should look into how to measure and set a custom white balance in your camera.

Another option is to shoot in Raw format instead of JPEG, and adjust the white balance afterwards, on the computer. If things get really critical, it helps to shoot with a known colour reference in the scene – something like a ColorChecker Passport. But you can get very good results using other options like a small WhiBal card, which is more subtle, more portable, cheaper and quicker maybe.

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  • \$\begingroup\$ Thanks for replying so fast. I am still in learning and recently I had browsed an article on this subject and had bookmarked it Understanding White Balance – A Beginner’s Guide, but had totally didn't recollect. With so many settings and using the camera occasionally only, it is difficult to recollect most of the settings and attributes. \$\endgroup\$
    – prasad_
    Commented May 17 at 10:47
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    \$\begingroup\$ I would normally leave the WB on "sun" mode. In every specific case, I carry a thick white paper (some papers have a whiteness level) And set a specific white balance. They are the only 2 modes I use. \$\endgroup\$
    – Rafael
    Commented May 17 at 18:34
  • \$\begingroup\$ @osullic I did try the WB settings and tried the photos again with change in setting and get results as seen by naked eye (and as expected). This experience will make me remember this aspect well. I also noted that the camera's fn button is pre-programmed, by default, to access the WB setting. \$\endgroup\$
    – prasad_
    Commented May 18 at 1:59
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To give a somewhat practical answer... I notice there is what looks like a wall or something in the foreground (quite out of focus) in the "more correct" picture. This wall appears to be white, which suggests the camera was able to use it as a white-balance reference, whereas the first had no such reference and the camera had to make a "best guess". Other Answers explain how white balance caused the problem; I thought I'd take a shot at why it might have happened.

I would be really interested to see the unadjusted (i.e. no color correction / white balance and minimal levels/contrast correction) raws side by side; probably they are a lot less different. On which note, I strongly recommend, if you can afford the storage, to always, always shoot raw. A raw has a greater dynamic range, and if the camera does something like horribly botching the white balance, post-processing from the raw will give you a result as good as (or better than!) if the camera had gotten it right, whereas trying to fix the already-processed image is a lossy process. In general, you can do better processing offline than what the camera does in-body. (Arguably you can even get better debayering results from offline processing, particularly as you have the ability to change algorithms depending on what you're shooting.)

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  • \$\begingroup\$ "... notice there is what looks like a wall": Yes, its a wall. Thanks for posting an answer. Yes, I have thoughts about shooting RAW, and mostly didn't want to enter the post-processing right now (as it involves more technology and terminology and time). I understand it allows lot of flexibility and noted that there are corresponding settings in camera as well. The camera allows shooting RAW+JPEG. I am using the Nikon's NX Studio, and did go thru their manual and some tutorials, and have some introduction. \$\endgroup\$
    – prasad_
    Commented May 18 at 2:11
  • \$\begingroup\$ @prasad_, the great thing about shooting both is that you don't have to use the raw, but it's there if you need it. \$\endgroup\$
    – Matthew
    Commented May 18 at 18:44
  • \$\begingroup\$ There's no such thing as an "unadjusted raw". See also: RAW files store 3 colors per pixel, or only one? \$\endgroup\$
    – Michael C
    Commented May 18 at 21:33
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    \$\begingroup\$ @MichaelC, I mean the RAW processed only with debayer and basic level shifting, but (critically) without any color correction (white balance). Also, you're sort of making an overly pedantic point; certainly there is such a thing as a "raw" RAW. You might not be able to see much looking at such a file, but the file itself should be darned close to what the sensor reported with minimal further processing. (Where ISO gets applied in this process, I'm not entirely sure...) \$\endgroup\$
    – Matthew
    Commented May 20 at 16:50
  • \$\begingroup\$ @Matthew There is no color in a raw file. Each pixel is a single luminance value. The 3 colors of the filters over the sensors in cameras are not the same 3 colors as those emitted by our monitors. There HAS to be WB applied to raw data to synthesize color. That's why different raw convertors can show radically different colors when opening the same raw file, they each have different default methods for applying color settings. What you are describing as uncorrected is the default color processing settings for the app you're using to open the raw file, not anything intrinsic to the raw file. \$\endgroup\$
    – Michael C
    Commented May 21 at 20:31
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Why the color is different in two pictures in similar conditions and setting?

Because you told the camera to use Auto White Balance and then, in the "eyes" of the camera's logic system, presented two different conditions/settings.

The second image has a area area to the right that the camera interpreted to be what should be neutral white, so it adjusted the WB to make that large area with the same light color close to neutral white.

The first image has nothing in the frame that looks anything like a neutral white/gray object in it, so the camera used a different method to determine WB in that image.

The two different conditions in the frame which led to two different methods used by the camera to automatically determine WB led to two different WB results.

White Balance is needed because not all light sources emit the same combinations of wavelengths of visible light in the same relative amounts. Without adjusting for WB, the same objects would show up under various different light sources as different colors. Our eye/brain system is usually very good at adjusting for the differences in light sources so we perceive the same object is the same color under most light sources, particularly those that are natural or mimic natural light sources such as the sun, a burning bonfire, a coal oil lantern, or a tungsten light bulb. Cameras, on the other hand, aren't as adaptable as our eye/brain vison system is, though they keep getting better and better all the time.

Related:
What factors affect a camera's ability to accurately perceive color?
How do I find the right white balance value to set in my camera?
This comprehensive answer to What exactly is white balance?
What is white balance in a camera? When and where should I use WB?

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As we compose each picture we take, the camera’s logic (automatic mode) chooses the shutter speed and aperture setting based on its built-in logic. The results, most of the time, will be very satisfying. Sometimes this camera logic fails, and the outcome is deemed substandard. Note the camera measured the color temperature of the vista as 7750K for the first and 4650K for the second.

Now, photo scientist measures the ambient color of light playing on a vista using a system called “color temperature”.

Note: Your first picture is assigned 7750K and your second picture assigned 4650K by your camera. Why is this?

The logic of the camera averages the colors of the vista being photographed. The method used varies from camera to camera, nevertheless, in auto mode this value is called an integrated color balance. This value will change based on the distribution of colored objects in the composition. Note one image shows more blue-sky than the other.

The color balance data is used by the built-in computer logic of the camera to apply a correction factor that will hopefully make the resulting image more “faithful”.

Most of the time this scheme works well. When it fails, we old photofinishers have coined the words “Subject Failure” to classify this error.

Study your camera manual for workarounds that thwart this failure.

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  • \$\begingroup\$ Thanks for posting an answer. Noted there are "photo scientists" (new terminology for me). \$\endgroup\$
    – prasad_
    Commented May 18 at 2:16
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    \$\begingroup\$ Color Temperature is but one axis in a three dimensional color space model. As you are well aware from your background in color film development, not only must we compensate for variations in color temperatures, but we often also need to compensate for variations in tint, which is the green←→magenta axis more or less orthogonal to the CT axis, even when the CT is the same for two different light sources, such as green tinted fluorescents at 4200K or magenta tinted LED lights also at 4200K. \$\endgroup\$
    – Michael C
    Commented May 18 at 21:40

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