Architectural photography and its methods have evolved over many years. Much of this is due to the advances in lighting technology, and more recently, in cameras, and computer hardware and software.
Let's work our way through the evolution, starting with the basic camera, then discuss the image capture media (originally film), and how the camera/capture methods have evolved.
Camera: The main features of the camera are the lens, shutter, and image capture media. Now, this will get a bit technical. For architectural photography, where the building walls need to be kept parallel and vertical, the film plane needs to be kept vertical to accomplish this. So in order to capture the building, many times the lens needs to be moved independent of the film. (We can't tilt a normal camera up, or the film plane will tilt as well, and the building walls will now converge to the top of the building or room in the final image.) Originally, the camera of choice was a view camera. The lens could be slid vertical, or even tilted. This allowed the camera to capture the building properly, and still keep the film plane vertical, and the walls would then be captured vertical. Some photographers still use view cameras, with their inherent features. These cameras have been modified now, to use digital backs to capture images. (The original large view camera has largely
been made obsolete now, since it will only shoot film.) However, using special lenses, we can still accomplish the same thing. New lenses for digital SLR cameras, called tilt/shift lenses, allow the lens to move in relation to the digital sensor. This allows the camera to be adjusted to keep the verticals parallel, and still capture the building.
Now onto the image capture media. This was originally silver-based film. This involved chemistry in the film itself, and then in processing the film to get an image. Decades of work by chemists made this method very advanced, resulting in very good results. Over the last 15 years, digital capture, using solid state sensors, has largely taken over from film. The advent of personal computers, image-processing software, amazing cameras, and speed of the obtaining final results has transformed the photography industry.
With these new tools, the camera/capture methods have also evolved. Let's discuss some of those methods.
1. One exposure, no supplemental lighting - this is the original ( and still used) standard. Adjust the camera settings to get a good exposure using the existing lighting and you have your image.
2. One exposure, supplemental lighting only- this utilizes the supplemental lighting as the main lighting. This could be either continuous lighting, like tungsten lights, or flash. The existing lighting is too dark to be a significant part of the image; the supplemental lighting provides all the significant light falling on the scene.
3. One exposure, additional supplemental lighting in combination with existing lighting - this technique balances the existing lighting with the supplemental, so we "fill" the shadows with the supplemental lighting. This can be done with continuous tungsten lighting, as well as flash.
4. Multiple exposures, on one capture medium - this technique utilizes multiple exposures going directly on one media, for example, one piece of film. For example, at sunset, the lighting changes quickly. The first exposure could capture the exterior of the building, and the sky. Then, if we wait for the sun to go down, and the building interior lights to come on, we can then photograph for the building lights, adding them to the image on the same medium. This requires a slower shutter speed. OR
We could photograph an interior in multiple exposures, using the existing light on one capture, then adding flash on other exposures. OR
We can use a technique called "painting with light". This involves using a moveable continuous light, and adding light to parts of the image as the shutter is left open. Total darkness is required, and just the light we add is captured.
5. Blend many separate exposures using computer and software, no supplemental lighting - This is a combination of 1. and 4., the intent is to get good exposures on ALL of the image areas. But with the advent of computers and image processing software, we don't have to try and do it on one capture media. We can take all the separate exposures, and blend them together in the computer. This allows the balancing of all the separate exposures into a great final image. We can use a technique called HDR photography. Here different exposures are made, some to capture the bright spots in the image (sky, for example), and then others capture the shadow areas properly (and let the sky go white). These separate exposures are blended together using special software, where properly exposed parts of the multiple exposures are used and blended together to make a natural-looking scene, just as your eye sees it in many cases.
6. Blend many separate exposures, use additional supplemental lighting - This is a combination of 2. and 4. Supplemental light can be added either continuously, as with the "painting with light" approach; however, this isn't too practical since total darkness is required. OR
We can add the light as multiple flashes. Since the flash lighting is quite strong, total darkness is not required, and this techniqe can be done in subdued daylight. The main advantage of this technique is that supplemental light can be added within the scene. That is, the light source can be located where it is actually visible in the image. Then using computer software, we can remove the light-generating device, and only leave the resulting light it cast on the scene.
This last technique, the "constructed" approach, adds one more important technique to obtain great photographs. This technique goes one step beyond even the new HDR technique, and can add light to small areas of the image, to highlight those areas, and draw attention to them. To accomplish this with existing image captures would require lots of computer work, and may appear strange in the end. While this technique is quite new, some other photographers are already using it to create incredible architectural images.
As with all things new, it takes a bit of time for adoption; however, the technique is so powerful that it is only a matter of time before most architectural photographers will learn and use it for many of their images.
