Exposure Fusion is quite different in many ways then HDR. The only resemblance the two have are that they combine a sequence of bracketed images together. That is where the similarities end. First of all Exposure Fusion is a low dynamic range result rather then a high dynamic range. This means that the final product looks more realistic to how the scene really would like. This means that the shadows maintain a certain amount of shadows and the highlights remain brighter in higher tonalities then a high contrast scene. HDR takes the sequence of images and blends the images seamlessly but does its best to even the tonalities in the extreme tonalities of shadows and highlights. This is what gives HDR the appearance of artificiality and unnaturalness. Exposure Fusion after fusing the images together keeps the tonalities how they would appear if one was to be looking at the actual scene being photographed. When one views a HDR image a keen photography eye can spot the uneven transition between the luminance and can therefore lose the appeal of realism. Now I am not saying that one is better then the other in terms of an artistic point of view but that Exposure Fusion produces results that are truer to the scene that the photographer is trying to capture.
Exposure Fusion Advantages Over HDR
Exposure Fusion processing times takes much less due to a absence of a intermediate HDR image that must be created before one can tone map a HDR image. Thus, processing times are twice as fast when transferring back into Photoshop. The most important advantage in Exposure Fusion is the lack of halos that appear around objects that occur with HDR. Often when combining images HDR produces a very three-dimensional image that looks very impactful but when viewed closer the halos become more evident. As a side note eliminating those halos in HDR can be quite difficult and time consuming. To get around the problem of halos in HDR layer masks and careful brushing is essential.
One very important advantage of Exposure Fusion is that it can combine a series of bracketed images with different depths of field that extend the Depth Of Field in an image and give the perception of more three-dimensional qualities in the image. This presents an advantage to many obstacles when it comes to nature photography. For example, shooting a wide perspective of a scene with wildflowers and a mountain in the distance would normally require a f/16 at least to get everything in focus. The problem arises if there is strong wind or low light and a faster shutter speed is needed to freeze the detail in the foreground wildflowers. It is then necessary to shoot at f/8 for the foreground and combine it with the rest of the images which can be shoot at f/16 to capture the background mountains. Before Exposure Fusion combining a series of images with different Depths Of Fields was limited to only those with the best of Photoshop skills.
