What Is Photo Enlargement?
image by Tom Moreland
A photo enlargement for film is a print or projected reproduction that exceeds the dimensions of the negative or slide frame. In digital photography, the print is an enlargement of a computerized picture file--usually in the JPEG format. It is important to understand how an enlargement affects picture quality.
Enlargements in the Strict Sense
Most film negative frames are on 35-mm-wide rolls. In regards to digital photography, the equivalent of the film negative would be the thumbnail image. The standard enlargement size for prints from both negatives and thumbnails is 4 by 6 inches.
The Popular Understanding of Enlargements
Strictly speaking, a photo enlargement would be any print size or electronic representation larger than the negative or print-file source. But, enlargements are more popularly thought of as any print or representation beyond the standard 4 by 6 or snapshot size.
Grain and Pixels
A photo enlargement not only enlarges the overall picture, but also increases the size of the grain in the film emulsion or the pixels (square, electronic units that make up the image) in a digital image. The picture will become more grainy as the size of enlargement increases. In digital photography, the individual pixels become larger.
Focus or the Lack Thereof
Just as the composition of the image source is increased by an enlargement, so is the quality, or lack thereof, of the picture's focus. A thumbnail-size image of a given picture could look reasonably sharp. But, an enlargement will aggravate any imperfections in focus. In other words, the larger the print size, the more out-of-focus or softer a picture will become.
Standard Enlargement Sizes
Traditionally, photo labs have offered 5-by-7-inch and 8-by-10-inch print enlargements. In the past, anything larger from a 35-mm negative would be of an unacceptably low quality. But, with the increase in the pixel count of digital cameras and the conversion of 35-mm negative images to picture files, sharp prints of 11 by 14 inches up to poster size can be made.
The photo at the top of the page has been cropped by enlarging.
Cropping by Enlarging
You can crop an image by enlarging it. Basically, this is accomplished by zooming in on and printing only a particular area of the picture. Horizontal photos can be converted to vertical and vice versa in this way.
- Picture Correct, Advanced Photo Enlargement Processing
About this Author
Earl Moreland has written for 35 years. His latest work, in addition to Demand Studio articles on society, culture, outdoors and religion, involved feature stories for Life In Sebastian County (Fort Smith, Ark.). He has a B.A. and M.A. in journalism and an M.Th. in theology.