There are lots of reasons why we like to take photos of our models and our layouts. For some of us, photographing models has become a hobby within a hobby. As with any technology, taking good photos with today’s digital cameras requires a certain level of understanding of how they work. With that understanding we can consistently get the best results possible from the camera we’re using. The purpose of this article is to describe the fundamental principles which impact taking quality images of our modeling and how these principles translate into practice when photographing them.
It is a common misperception that an expensive camera is needed to take model photos. There are cameras available new in the $300 – $500 price range that have the needed capability. To be appropriate for model photography it is essential that a camera have at least a minimum level of user adjustability. Specifically, it must have a user-adjustable lens aperture (“Aperture Priority Mode”) and, second, it must have a user-adjustable focus point (i.e., the user can determine what object in the scene the camera will focus on). Most cameras with these attributes will also have a variable shutter speed and automatic shutter release feature, and many will have a lens with an adjustable focal length (i.e., a telephoto or “zoom” lens).
Depth of Field (DOF)
Perhaps the factor most important to the success of a layout or model photo is having as much of the image as possible in focus. The amount of a photo in focus is referred to as the depth-of-field (DOF). Generally speaking, we want the DOF as big (deep) as possible, preferably encompassing the entire scene.
Technically speaking, a camera lens is only in perfect focus along the “focal plane” (Figure 1). The focal plane is an imaginary plane running parallel to the camera through the object the camera is focused on, that point being called the focus point. As objects in the scene get farther away from the focal plane they become progressively less in focus. Fortunately, when the photo is printed or viewed on a computer, objects for some distance in front of and behind the focal plane will appear “acceptably sharp.” The depth-of-field, then, is the total area in front of and behind the focal plane in which objects appear in acceptable focus. For all cameras the focal plane is about 1/3 of the way into the total depth of field. The diagram is not to scale and in reality the focal plane is a curved surface, not a flat plane…