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Fluorescent lighting gives a greenish cast to pictures
This means that you must compensate for the greenish cast in order to bring out the real color.
Greenish cast from
    fluorescent lighting.
Fluorescent lighting gives a greenish cast to pictures
Backlighting makes the main subject too dark
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Greenish cast from fluorescent lighting

 Photos taken under fluorescent or mercury vapor lights have a greenish cast.
 Color compensation can be used to bring out the actual color.
 Fluorescent lights contain a strong green component, to which the human eye is not very sensitive. Therefore, daylight balance slide film or a digital camera set for daylight white balance records far more green than you can see when taking a picture. This greenish cast results in a very unpleasant looking photograph. Fortunately, this unwanted greenish cast can be removed.
 There are several methods for removing colorcast. In Photoshop, you can use the special eyedropper to correct the portion of the picture that should be neutral gray, thereby correcting the overall color balance.

1 Open the picture file.


  Pictures like this are common when taken in office buildings, subway platforms, or residences with fluorescent lighting.

2 Select the eyedropper sample area


  From the Image menu > Color compensation > open Tone curve. (If using the Adjustment laver, from the main menu > New adjustment layer > open Tone curve.)
 Next, select the eyedropper target. Double-click on each of the three eyedroppers and set the target.
  Set the highlight eyedroppers for R, G, and B to 247. This sets the point clicked to 247 for R, G, and B. (See "column" for details about each target value.)
  The intermediate eyedroppers for R, G, and B are all 127. Since this is the value you want, no change is necessary.
  Set the shadow eyedroppers for R, G, and B to 7.

Column: [Tone Curve] eyedropper target setting
 The reason for setting the highlight eyedroppers to 247, the intermediate ones to 127, and the shadow ones to 7 is to prevent washed out highlights and lost shadow detail.
  If the highlight RGB eyedroppers are all set to 255, the result is pure white with no detail.
  If the shadow RGB eyedroppers are all set to 0, the result is pure black with no detail.
  That is why we set the highlight eyedroppers to 247 and the shadow eyedroppers to 7.
  The total range of a digital image is 0 to 255, or 256 steps, so the intermediate eyedroppers are set to the halfway point of 127.
 We will use these values for these lessons.
  These are not absolute values, but we will use them as our standard values.

3 Click on the highlight eyedropper


 Now that the eyedropper target settings are fixed, click inside the image with the highlight and intermediate eyedroppers.
  The highlight eyedroppers for RGB are set to 247 to give a neutral white. Therefore, click on a point in the image that should be white. The point will become a white highlight and the RGB color balance will be corrected automatically.



 As with the highlight eyedropper, which was set to a neutral white, the intermediate eyedropper is set to a neutral gray (RGB = 127). Clicking on a point that should be gray will automatically adjust the color balance. In the sample illustration, a part of the ceiling is indicated. Unpainted concrete is usually gray. The clothes of the person in the foreground are also white/gray with a greenish cast. By clicking on the ceiling, you can correct the color of both the ceiling and the dress. Now click. You should see a significant improvement. This type of adjustment is quite effective at correcting the greenish cast caused by fluorescent light. If you are not satisfied with the results, change the sample point and click again.




 You haven't yet used the shadow eyedropper, but the highlight and intermediate adjustments have already done an excellent job of correcting the greenish cast, and you don't even need to use the shadow eyedropper. Leave Tone curves open and proceed to the next step.

4 Tone Curve Compensation


  Although the eyedropper is very convenient for setting standard gray, it is not appropriate for use for fine brightness compensation. Therefore, continue to work with Tone curves. Since the basic color compensation was set with the eyedroppers, only the RGB curve is adjusted by Tone curves. In order to brighten the overall feeling, some shadows will be made brighter, and the middle tones to highlights will also be brightened, and the highlights made cleaner.
  Click OK to set the changes.
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