Lenses View camera

a view camera lens typically consists of:

a front lens element— referred cell.
a shutter—an electronic or spring-actuated mechanism controls exposure duration. shutters air-actuated. long exposures, lens no shutter (a barrel lens) can uncovered duration of exposure removing lens cap.
the aperture diaphragm
a lensboard—a flat board, typically square in shape , made of metal or wood, locks securely front standard of particular view camera, central hole of right size insert lens , shutter assembly, secured , made light-tight screwing ring onto thread on rear of lens assembly. lensboards, complete lenses, can removed , fitted quickly.
a rear lens element (or cell).

almost lens of appropriate coverage area may used view camera. required lens mounted on lensboard compatible camera. not lensboards work models of view camera, though different cameras may designed work common lensboard type. lensboards come hole sized according shutter size, called copal number. copal popular maker of leaf shutters view camera lenses.

the lens designed split 2 pieces, front , rear elements screwed, trained technician, front , of shutter assembly, , whole fitted in lensboard.

view camera lenses designed both focal length , coverage in mind. 300 mm lens may give different angle of view (either on 31° or on 57°), depending on whether designed cover 4×5 or 8×10 image area. lenses designed cover more image area accommodate camera movements.

focusing involves moving entire front standard lens assembly closer or further away rear standard, unlike many lenses on smaller cameras in 1 group of lens elements fixed , moves.

very long focus lenses may require camera fitted special extra-long rails , bellows. short focal length wide-angle lenses may require standards closer normal concertina-folded bellows allows. such situation requires bag bellows, simple light-tight flexible bag. recessed lensboards used rear element of wide angle lens close enough film plane; may of use telephoto lenses, since these compressed long-focus lenses may have small spacing between of lens , film plane.

zoom lenses not used in view camera photography, there no need rapid , continuous change of focal length static subjects, , price, size, weight, , complexity excessive. lenses convertible : front or rear element only, or both elements, may used, giving 3 different focal lengths, though quality of single elements not @ larger apertures combination. these popular field photographers can save weight carrying 1 convertible lens rather 2 or 3 lenses of different focal lengths. older convertible lenses may not corrected chromatic aberration, making them unsatisfactory color film.

soft focus lenses introduce spherical aberration deliberately optical formula ethereal effect considered pleasing, , flattering subjects less perfect complexions. degree of soft-focus effect determined either aperture size or special disks fit lens modify aperture shape. antique lenses, , modern slr soft focus lenses, provide lever controls softening effect altering optical formula.