Large format: Difference between revisions

'''Large format''' photography refers to any imaging format of 4×5 inches{{cvt|9 (102×127 mm)× 12|cm|in}} or larger. Large format is larger than "[[medium format]]", the 6×6 cm{{cvt|6 (2¼×2¼× inch)6|cm|in}} or 6×9 cm{{cvt|6 (2¼×3½× inch)9|cm|in}} size of [[Hasselblad]], [[Mamiya]], [[Rollei]], Kowa, and [[Pentax]] cameras (using [[120 film|120- and 220-roll film]]), and much larger than the 24×36 {{cvt|24 × 36|mm (0.95×1.42 inch)|in}} frame of [[135 film|35 mm]] format.

The main advantage of a large format, film or digital, is a higher resolution at the same pixel pitch, or the same resolution with larger pixels or grains which allows each pixel to capture more light enabling exceptional low-light capture. A 4×5 inch image (12.903 mm²) has about 15 times the area, and thus 15×15 times the total resolution, of a 35 mm frame (864 mm²).

The most common large format is 4×5 inches (10.2x12.7 cm), which was the size common cameras used inby the 1830s-1950s,cameras like the [[Graflex]] [[Speed Graphic]] and Crown Graphic, among others. Less common formats include quarter-plate (3.25x4.25 inches (8.3x10.8 cm)), 5×7 inches (12.7x17.8 cm), and 8×10 inches (20×25 cm); the size of many old 1820s1920s [[Kodak]] cameras (various versions of Kodak 1, 2, and 3 and Master View cameras, to much later Sinar monorail studio cameras) are 11×14 inches (28x36 cm), 16×20 inches (41x51 cm), 20×24 inches (51x61 cm), various panoramic or "banquet" formats (such as 4×10 and 8×20 inches (10x25 and 20x51 cm), and metric formats, including 9×12 cm, 10×13 cm, and 13×18 cm and assorted old and current aerial image formats of 9×9 inches, 9×18 inches (K17, K18, K19, K22 etc.), using roll film of 4, 5, 6, 7, 9, or 10 inches width or, [[view camera]]s (including [[pinhole camera]]s), reproduction/process cameras, and x-ray film.

[[File:Adams The Tetons and the Snake River.jpg|thumb|right|[[Ansel Adams]]'s large format photograph ''The Tetons and the Snake River'' (1942).]]

Large format photography is not limited to film; large [[digital camera back]]s are available to fit large format cameras. These are either medium-format digital backs adapted to fit large format cameras (sometimes resulting in cropped images), step and repeat Multishot systems, or [[Digital scan back|scanning backs]] (which scan the image area in the manner of a flat-bed [[Image scanner|scanner]]). Scanning backs can take seconds or even several minutes to capture an image. When using a [[Sinar]] Macroscan unit and 54H data files, over 1 [[gigabyte]] of data is produced.

Large format, both film-based and digital, is still used for many applications, such as landscape photography, advertising photos, fine-art photography, scientific applications and generally for images that will be enlarged to a high magnification while requiring a high level of detail. High quality fine art prints can be made at sizes in the range of 40x50"40x50″ from a 4×5"4×5″ original, and well beyond that for larger negatives.

Large format film is also used to create a record of historic resourcesplaces and things for the [[National Park Service]] documentation programs. The [[Historic American Buildings Survey]] (HABS), the [[Historic American Engineering Record]] (HAER), and the [[Historic American Landscapes Survey]] (HALS) require large format film-based photography. 4×5"4×5″, 5×7"5×7″, and 8×10"8×10″ large format film formats are the only acceptable formats for inclusion in these collections at the [[Library of Congress]]. 4x5 and 5x7 are generally used in the field (5×7"5×7″ is preferred for very significant buildings) and 8×10"8×10″ is generally utilizedused for photo-duplication of historic photographs, documents and blueprints. Through HABS/HAER/HALS, buildings and sites of historic significance are recorded with large format cameras and black and white film and using techniques that document the key features of the historic resource with special care not to distort the angles and views. This rectified photography can be accomplished with large format cameras by keeping the film, lens and subject perfectly parallel. Smaller format cameras need to be tilted to view high or low subjects, but the same subjects can be captured by shifting the lens element of a large format camera up or down to keep the film, lens, and subject planes parallel.

HABS, HAER, and HALS also requires the increased resolution of large format film. A sheet of 5×7"5×7″ film has almost twice the resolution of 4×5"4×5″ film, and 4×5"4×5″ is almost 16 times larger than a 35 mm film image (24×36 mm). This added negative size not only allows for more detail, but the large format [[polyester]] film is also far more durable than [[acetate]] 35 mm stock. HABS, HAER, and HALS require that all submissions to the Library of Congress include the original film (archivally washed) and it must also include contact prints on fiber-based paper; these contactcontacts are the same size as the film being submitted, 4×5"4×5″, 5×7"5×7″, 8×10"or 8×10″, and the large size allows people to readily see the prints, while 35 mm contacts would be too small and would require magnification.

* [[YousufEvelyn KarshHofer]] (8×104×5" portraits)

* [[Janelle Lynch]] (8x10" landscapes and portraits)

* [[Joel Meyerowitz]] (8×10" landscapes)

* [[Michael A. Smith (photographer)|Michael A. Smith]] (8×10", 8×20" and 18×22")