Large format camera
Large format cameras are a type of photographic camera that is differentiated according to the film format used; they use sheet film , i.e. individual sheets of paper on a relatively thick carrier material, to record images. In the past, photographic plates (glass plates) were used. They are still used today for special tasks, for example in astrophotography with its high demands on the dimensional accuracy of the recordings (see camera ). The larger recording format provides a much greater wealth of detail than medium and small formats. Sheet film is inserted in cassettes; 120 and 220 roll film can also be used in special cassettes. Formats such as 6 cm × 9 cm (medium format), 9 cm × 12 cm, 13 cm × 18 cm, 18 cm × 24 cm and larger are common. Non-metric formats such as 4 " × 5", 5 "× 7" or 8 "× 10" are also common. Single shots can be developed individually, quick series of images are not possible due to the camera construction and handling. High-performance digital backs for digital photography are also becoming increasingly important in the large format sector .
Large format cameras are offered in the following designs:
- Large format walking floor camera with rangefinder and triple floor extension, especially for mobile use
- Single format view camera on an optical bench , more for studio use
- Multi-format view camera on an optical bench.
Components
Large format cameras have the following components:
- The walking floor or the optical bench (a tube or a stable rail) on which are movably mounted:
- The front standard : It takes the interchangeable lens plate with the lenses.
- The picture standard : It carries the screen for setting and takes the sheet film cassettes or film magazines during the recording .
- Both standards are connected by a light-tight bellows made of leather or nylon.
Setting options
It is focused by changing the distance between the two standards.
Large format cameras offer extensive adjustment options:
- Elevation and depth shift
- Side shift
- Central swivel
- Vertical swivel
- Base pan
The horizontal or vertical shift (shifting) of the lens standard changes the image section and the perspective. The image section changes when the ground glass standard is shifted horizontally or vertically. With all shifts, the lens and ground glass standards remain parallel in every direction.
The horizontal or vertical pivoting (tilting) of the lens standard shifts the plane of focus. When the ground glass standard is swiveled horizontally or vertically, the plane of focus shifts and the perspective effect changes.
If you move the lens standard on the optical bench, the object distance and thus the image scale changes. In addition, it can be roughly focused. The fine focusing is done by moving the ground glass standard.
These adjustment options require lenses with a particularly large image circle and allow very extensive control over perspective and depth of field. The controlled adjustment of the focal plane according to Scheimpflug is a specialty of view cameras.
- Sketch 1 .: The camera is facing the right wing of the building without any adjustments. View: normal, left wing perspective
- Sketch 2 .: Camera position as 1., lens shifted to the right, camera rotated to the left until the building is completely in the picture again. Left wing smaller than 1., right wing stretched in perspective, vanishing point on the left.
- Sketch 3 .: Camera position as 1., lens shifted to the left, camera rotated to the right until the building is completely in the picture again. Left wing larger than 1., right wing stretched in perspective, vanishing point on the right.
- Sketch 4 .: The camera is offset to the left, facing the corner of the building. The camera is turned to the right, but not adjusted. Perspective representation with right vanishing point. Left wing larger than before, right wing smaller than before.
- Sketch 5 .: Camera position as 4., lens shifted to the left, camera rotated further to the right. Elevation of perspective compared to 4.
Large format digital photography
As in medium-format photography, digital camera backs are used in large-format photography that are attached to existing models. This is how old systems are supplemented. The resolution here (with one-shot systems) goes up to approx. 11000 × 7500 pixels (as of February 2007). In the still life area, scan backs for view cameras can also be used, which scan the image several times and thus achieve a higher resolution. There are numerous manufacturers who offer these digital backs. With the advancement of digital technology, more and more manufacturers are offering smaller models of their classic view cameras. They take into account the fact that the cameras are oversized for the relatively small digital sensors and more powerful film emulsions. Either digital backs or roll film magazines (up to 6 cm × 9 cm) can then be used on them. So-called “small view cameras” have the same adjustment options as their large analogue predecessors, but can be set more precisely and are much easier to handle. The same applies to the classic specialist lenses. You can use your old specialist lenses with a digital back, but in practice this is not very satisfactory. The focal lengths are far too long for the small formats (e.g. one would use a 72 mm wide-angle construction as a normal lens) and the quality of such large lens constructions is only mediocre, as they do not offer their format advantages and large image circles can play off.
Lenses
Lenses are available in the range from about 36 mm (for film format 6 cm × 12 cm; 47 mm for 4 "× 5") to 1,200 mm. Due to the relatively small recording area, wide-angle lenses from 24 mm focal length are also available for digital backs. The view camera lenses are mounted on lens plates and can therefore be used on various camera systems. This allows you to mount the lens on a different lens plate and use it on a different camera. Mounting on a new plate is relatively cheap. They are tailored to the respective maximum film format, so that the recording material can still be shifted in the aerial photo / image circle (up to 50 cm in diameter) of the lens.
As in the small picture area, a distinction is also made with the specialist lenses :
- Wide angle lenses
- Normal lenses
- long focal length lenses (analogous to telephoto lenses ).
This classification relates to the respective recording format. With an image format of 9 cm × 12 cm, lenses with a focal length of 135 mm or 150 mm are to be regarded as normal lenses. Lenses with a shorter focal length have a larger angle of view in this format, they are wide-angle lenses. Longer focal lengths have a correspondingly smaller angle of view.
There are also telephoto lenses . In contrast to "normal" lens constructions (e.g. repro lenses), the extension of which (distance between film plane and lens plane) corresponds to the specified focal length of the lens, telephoto lenses require a shorter camera extension due to a special lens construction. Analogous to this, one works in the wide-angle range with retrofocus constructions in order to increase the distance between the film and lens plane.
Today, the production of specialist lenses is severely limited, as the large recording formats are rarely used. The enormous progress in the development of ever finer-grained film emulsions , which even in the medium format (45 mm × 60 mm, 60 mm × 60 mm and 60 mm × 90 mm) show an excellent wealth of detail, is making the classic large format die out or as a niche for conventionally working people Photographers still exist. In addition, there are the digital cameras / digital backs on medium format cameras , which are constantly improving in quality, and the convenient options for digital image processing.
The exposure time when taking pictures with large format lenses is controlled either by built-in central shutters or by a rear lens shutter. The central shutter is built into the lens between the front link and the rear link. This means that every lens basically needs its own shutter. The rear lens shutter is located behind the taking lens on the camera. The corresponding lenses do not have their own shutter, but usually only an aperture mechanism .
Weber distinguishes three types of lenses:
- Fast lenses (speed f / 2.8–1: 3.5),
- Lenses with a large image circle diameter (light intensity 1: 5.6–1: 8) and
- Special lenses for areas of application such as macro and portrait photography (e.g. macro, soft focus and repro lenses).
meaning
The sharpness, richness of color, tonal gradation and richness of detail of large format photographs are superior to all smaller formats; Therefore, the main area of application of large format cameras is probably also the demanding architecture, landscape and industrial product photography carried out by professional photographers (in the photo studio). However, the setup is often time-consuming and complicated, and the equipment is very heavy and expensive. However, there are also large format handheld cameras.
Andreas Feininger points out that working with large format cameras is more difficult and time-consuming to operate compared to small format cameras; nevertheless, "the best camera turns out to be the largest [...] which can just barely be handled satisfactorily under the relevant recording conditions".
One of the best-known photographers who used large format cameras was the American landscape photographer Ansel Adams , who commented on the size of the camera in a similar way to Feininger: Always use the largest camera that you can just carry.
Others
The largest walk-in large format camera in the world with a size of 7 m × 4 m × 3 m is the Imago 1: 1 .
See also
Individual evidence
- ^ Ernst A. Weber: Photo internship . Birkhäuser Verlag, Basel / Boston / Berlin, 3rd revised. u. exp. Edition 1997, ISBN 3-7643-5677-4 , p. 91 f.
- ↑ Andreas Feininger: Andreas Feininger's great photo teaching (= Heyne-Ratgeber 5348). Heyne, Munich 2001, ISBN 3-453-17975-7 , p. 51.
- ↑ Ansel Adams The Camera ; Christian Verlag, Munich 1982; 8th edition 2000, ISBN 3-88472-070-8
literature
- Kurt Dieter Solf: Photography: Basics - Technology - Practice. Fischer Taschenbuch Verlag, Frankfurt am Main 1988, ISBN 3-596-23355-0 .
- Richard Grittner: Handbook of the camerawork: Lenses, cameras, accessories, enlargers, projector. Verlag Luitpold Land, Munich 1958, DNB 366027611 (a bit older, but essential for traditional camera technology)
- Leslie D. Stroebel: View Camera Technique. Focal Press, Boston, 7th Edition 1999, ISBN 0-240-80345-0
- Andreas Feininger: The high school of photography: the famous standard work (= Heyne-Ratgeber 4544). Heyne, Munich 1995, ISBN 3-453-41219-2 .
- Jost Marchesi: Photocall , Volume 2: Basics of optics in photography . Chapter 37
