The eye is easily deceived. It happened to me today. I was in a kitchen preparing to shoot a panorama. I set the camera (Nikon D80, 12-24 Tokina lens) to ‘Incandescent Mode’ and began shooting the pan. I thought the images looked slightly warm (orange/yellow), so I then shot the panorama on ‘Manual Colour Balance mode’ (using the white refrigerator to take the reading). Checking the images on the camera LCD panel, the second set of images seemed excessively blue and not usable.
How much can the eye deceive?
The left image was the one that was perceived to be usable, and the right image was the one perceived to be unusable.
Although a bit blue, the right image is more usable than the left image.
How is the eye deceived? The eye/mind adjusts to the overall colour tone of the available light and we then perceive the current lighting to be normal. So if the room has excessively yellow lighting, we perceive that as normal and neutral lighting. As a result, when checking the LCD panel of the camera to confirm the image quality, the image doesn’t appear yellow because the eye/mind is seeing yellow as normal. When viewing the second image in the same environment it seems excessively blue for the same reason.
The only way to avoid this deception is to move into an area that has balanced daylight, and then review the images on the LCD to confirm the colour balance.