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The largest fear that professional photographers have in switching to digital is image quality. In general, for printouts up to 8x10, it can now be said that image quality is the same; the debate that continues in photography magazines these days is around the ability to print high-quality images at poster size or higher. But then you must take into account film speed, film quality, and a host of other factors before making a strict, specific comparison. Here we will highlight the general differences. Difference #1: Tonal Range Film records wide differences in image tones (light to dark) with better quality. Digital camera sensors are more susceptible to adding noise (equivalent to grainyness) in darker toned areas of an image, especially with a higher ISO setting. Digital cameras also tend to show an unexpected edge in very bright areas as the image hits an overexposed area, rather than blending neatly the way film does. Difference #2: ISO Digital cameras allow you to change the ISO equivalence (or film speed) on a per-shot basis. Film cameras restrict ISO per roll of film. Difference #3: In-camera deletion of images Digital cameras allow images to be deleted at any time, which is handy for those of us who take fifty shots of the same rock! It also means less time editing images post-shoot, and less money spent printing duds. Difference #4: Long-term image storage Modern slides nad negatives can last several decades if stored correctly. Digital images can be stored on disk, with backup to CD or DVD, but each type of storage device has been branded with a lifetime of less than 10 years. What this means is that digital images have the capacity to last forever, provided you make more than one copy, and transfer images every 10 years from one storage device to a newer one. Difference #5: Print size With digital images, the largest print you can make that is of high quality depends on the number of megapixels used by the camera to store the image, along with the software youre using to enlarge the image, and the printer quality. Film negatives can generally be enlarged larger than a 6MP camera, but digital files in general can be pushed beyond their supposed size limits better than files made from scanning film. Difference #6: White balance Colour balance of a film is set at manufacturing time, which means you must add a filter to your camera to compensate for conditions where such colour balance is not appropriate. A typical example of this is shade conditions outdoors, where most films result in a blueish tinge. Digital cameras allow you to set the white balance per shot, and often come with presets based on standard situations (higher end cameras allow you to set custom white balance values, too). |
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