Digital Photography

Advantages | The Digital Darkroom

Digital photography offers two distinct advantages over traditional photography; captured images can be evaluated immediately and re-shot if necessary, and once captured, the quality of the image can be maximized through digital post processing.

Digital photography is also at the foundation of many new two and three dimensional documentary techniques. Digital photography not only provides the digital equivalent of traditional film based photographic images, but also captures the information used to create Panorama's, Object movies, polynomial texture maps (PTM's), and true geometric 3D Imaging. A solid understanding of digital photographic techniques is the pre-requisite for many advanced documentary methods.


Advantages

Digital photographers use the same basic optical and compositional skills as their film counterparts, but here the similarity ends. With digital photography, the results and the camera settings employed can be seen immediately. This permits on the spot adjustment to settings and compositions. When the camera is controlled remotely by computer, the full resolution digital capture can be examined for focal sharpness and fine compositional details.

This is particularly valuable when the objects being imaged are small, where imperfections like lint or dirt can escape the naked eye, and depth of the focus field is limited. Immediate image quality assessment is also invaluable on remote location. When shooting 'on site' and re-shooting the subject is either costly or impossible, knowing that the shot is 'in the can' is a clear advantage.

Additionally, knowledge of digital processing techniques allow photographers to adapt their methods to capture images that would be impossible with non-digital means. Most cameras, whether film or digital, have limited capability to document high dynamic range (HDR) subjects, where the subject contains both very bright and very dark elements. A photograph of a bright stained glass window in a dim cathedral will be unable to capture the entire subject. Either the cathedral will be properly exposed and the window will be overexposed, or the window will be properly exposed and the cathedral interior will be underexposed. A digital image processing technique known as high dynamic range imaging can take, multiple standard, limited dynamic range, images shot at different exposure levels and combine them, yielding a result containing the proper illumination for each element in the scene.


The Digital Darkroom

Digital image processing enables the optimization of information contained in digital images. While it is possible to alter digital images for creative or deceptive purposes, careful use of the digital darkroom in cultural heritage documentation makes the most of the image's inherent empirical content. Operations such as exposure correction, color cast elimination, sharpening, noise reduction, dynamic range extension, correction of optical distortions, and preparation for web distribution are routinely done in the digital darkroom.

Standard digital photographic practice incorporates a basic image processing workflow which is applied to each 'keeper' photograph. Additional processes may also be applied as desired.

Many powerful applications like Adobe Photoshop make robust image processing tools widely available.