Using the auto bracketing feature on my compact camera, I took this image of a grimy double bend sign, using an angle to ensure the first corner is visible in the shot. All unaltered images below. I did this twice, once when over exposing and the second underexposed. As expected the histogram for the over/underexposed images was biased to either the dark or light side, with the overexposed images with significant elements of the picture showing as pure white. No end of adjustments could bring back much if any detail in the large overexposed areas of the overexposed images, whereas detail could be gained from adjustments to underexposed images. The overexposed images did, however extenuate the road, which is a key part of the content. While this might be a helpful part of the place element of content, the overexposure has altered the form, as the grimy sign and associated texture is much less well defined.
In the underexposed images, all that the contrast was able to do was highlight the skyline, which wasn’t the intended content
I’ve noticed before how grass can become very bright, have a strong yellow component and unreal in colour when an image is overexposed. This is very evident when reviewing the green in each of the exposures.
My only conclusion for this content is that, in this instance the under and overexposure of this image distracts from the intended content, thus the image with a wide range of tones, and none against the extreme white end of the histogram worked best.
In some cases, changing the form through under or overexposure, changes the content. For example, the following image was deliberately underexposed to make sure the no entry sign became the main subject.