These photos illustrate the effect seen when using high shutter speeds under fluorescent lights. Fluorescent lights with the older type magnetic ballast cycle at twice the mains frequency. So short exposures, particularly shorter than 1/120s here in US, will result in incorrect exposure and white ballance.

A D300 was used for the first three photos. It's sensor relies upon the focal plane shutter slit to properly expose the sensor. Each curtain of the D300 takes approximately 2.5 milliseconds to traverse the sensor. That's about 1/400s. That travel speed does not change for very short exposures -- like 1/5000s. Only the delay between the first and second curtain is reduced meaning at 1/5000s the slit is going to be rather thin, but the top and bottom of the frame are always exposed about 2.5 milliseconds appart.

The first photo shows what a longish exposure looks like of a white sheet of paper. I intentionally underexposed the sheet. I used this exposure setting to take a preset WB of the paper. Note that the paper is a neutral shade of gray. Exposure was 1/20s, f/10, ISO200.

The next two photos where shot at the same equivalent exposure value, but at a much higher shutter speed. 1/5000s, f/1.8, ISO1600. The only difference is when the exposure was made relative to the fluorescent light's cycle.

Note that the second photo is overall very blue. I'm guessing this was taken near the peak of the light's cycle.

The third photo was taken at the bottom of the cycle. Notice the yellow band in the middle. The blue channel in the center of the yellow band is at zero. The red channel maintains its intensity but the green is down a bit as well relative to the peak photo.

The last two photos are of the same light taken with a D70. It has a global electronic shutter so the entire sensor is exposed at the same instant. This will create a more uniform exposure from top to bottom but the lamp cycling is still obviously a problem. The vignetting of the lens wide open is more obvious. I used the camera's fluorescent WB setting for these shots so colors may not be directly comparable with those from the D300.