Tripod

The tripod (Latin: stativus, a to fixed) guarantees a stable line-up of cameras, lights, microphones, laboratory instruments or measuring instruments.

A tripod has several telescopic legs which are variable in length as a rule. For heavy equipment, for reasons of strength sometimes fixed legs cheaper - eg telescopes for astronomy. Metal or wooden tripods have each typical advantages and disadvantages - for example, in mass, vibration, temperature and weather resistance.

• 3.1 Structure 3.1.1 tripod legs
• 3.1.2 tripod mount
• 3.1.3 Fluid Heads 3.1.3.1 Fluid Head
• 3.1.3.2 friction head
• 3.1.3.3 centrifugal head
• 3.1.3.4 socket head

Surveying Tripods

Particularly robust and stable, some surveying tripods plated (also tripod) in painted or plastic timber. You can carry weights up to 20 kg and still get over themselves so little that measurement accuracies up to one arc second (1 ") are possible.

The ash wood is often used for the tripod legs is particularly durable, relatively heavy, but provides very good vibration absorption. Through the paint, it is also insensitive to wet weather.

Characteristic of surveying tripods is the massive tripod head (usually made of cast aluminum ) with its circular opening of 6 to 8 cm in diameter. Above her, the measuring instrument is clamped from below with the so-called heart screw. This strong bolt is hollow, so that through them one by optical plummet can target to the ground. Centering over the survey point by optical or by plumb line by slightly shifting the theodolite before the heart screw is tightened.

Photo Tripods

In camera tripods, a compromise is often made ​​in relation to surveying tripods. While it arrives in surveying tripods on absolute stability, it comes with camera tripods on maneuverability, versatility and weight. Camera tripods are therefore usually easier than surveying tripods, but also much more unstable. In addition, they often have an extensible center pillar through which the receiving stand point can be increased further still, so the stability is often drastically reduced. Some tripods to the center column can also mount vice versa, which allows extremely low consumption stand points. Tripods are usually used in photography to produce sharp, blur-free images in low light conditions ( indoor, dusk, darkness). But even in bright, harsh light helps a tripod for example, resulting shadows which compensate seem dark and detaillos. This is done using a multiple exposure. If very long focal lengths, camera shake is particularly large because of the small angle of view, so here is a tripod ( almost) is indispensable. Also, given the high packing density ( pixel pitch [ of Engl. Pixel pitch ] ) of image sensors of digital cameras, the tripod comes with a view to generating a high image sharpness to a new role, since the small pixel pitch much earlier (see rule of thumb for " hands-free limit" ) leads to blurring. In addition, the tripod allows a more careful camera alignment and image design. Using a tripod also allows the aperture further include what mostly to better sharpness of the lens leads. The focusing screen setting frequently used in large-format cameras requires mandatory use of a tripod. To avoid camera shake, there are some alternatives, but a tripod can not replace in any case.

You can:

• The sensitivity ( ISO / ASA ) increase, but what the grain size of the images amplified ( analog photography ) or the picture noise ( digital photography).
• Open the aperture and shorten the shutter speed, so that the depth of field is smaller.
• Use a flash.
• Use a camera or a lens with image stabilization.

Camera Tripods also help to support the weight of a heavy camera used. This is important for example in nature photography, where you point the camera, for example, a bird's nest to wait for the right moment. Especially large and heavy telephoto lenses have their own terminals for mounting on tripods.

The most common designs for photo tripods are:

• (Also known as Tripod ) Tripods constructed. They are often made ​​of plastic, the light metal is aluminum, but also from wood or carbon fiber reinforced plastic ( "Carbon" ) was built.
• (Also called Monopod ) Monopods ' are very handy to have much fewer moving parts and are lighter than tripods. They can not usually place it anywhere and serve only as a stabilizing factor. Main area of ​​application is the reportage and sport photography with telephoto lenses.
• Studio stands are mostly used as a stationary studio photography because they allow a large range of vertical movement.
• Tabletop tripods, or mini tripods are very small. They are often used for small digital cameras or webcams.
• Clamping tripods are built in the shape of a screw clamp. Ensure that cameras and accessories, especially to objects such as tabletops, railings or windows can be secure. This can be especially helpful to take pictures out of a car.
• Shoulder stands and tree stands are more types of photo tripod.

Special forms of tripods are:

• Suction cup tripod. They are used for fastening to / on smooth surfaces such as windows or car roofs
• Beanbags. Granulate filled bags to the base and shape of the camera can be modeled appropriately to enable a relatively stable positioning of the camera
• Tree screws, integrated into positioning fixtures are most easily by hand in bark or wood columns screwed
• Magnets can be controlled or flexible, and thus removable stick on iron surfaces
• Mini tripods with three plastic flexible gooseneck legs that terminate in rubber balls,
• Special clamping tripods, for example, with three flexible, rubberized " poor" for embracing of solid objects such as light poles or branches
• Chain stands as a special form of the monopod

Tripod head

Between tripod and camera usually sits a tripod head, which allows the movement or the camera orientation. This can be a ball head (also called " ball joint head"), a three ways Eiger or Getriebeneiger be. Special tripod heads are panoramic heads, for taking panoramic photographs from many individual images. In order to accurately line up the frames together, have panoramic heads usually have graduated and water balances for each axis of rotation ( "Dragonfly "). If different cameras used with the same tripod, features of the tripod head with a quick release plate is helpful.

Tripod thread

As a tripod socket is called the screw for the held- device. For historical reasons, many do not have a tripod connections metric ISO thread, but that based on the inch system Whitworth thread with 55 ° edge angle. The UNC - threads of the same size has 60 ° flank angle, it can clamp or because of the tolerances sometimes fit.

• At viewfinder cameras, SLRs, medium format cameras, quick release plates and tripod heads a 1/4-Zoll-20-Gang-Whitworth-Gewinde (about 6.35 mm outer diameter and 5.2 mm inner diameter, pitch 1.27 mm ) was used.
• Some medium format cameras and virtually all large format cameras as well as most connections between tripods and heads use 3/8 " 16-speed Whitworth (approx. 9.6 mm outer diameter and 8 mm inner diameter, pitch 1.5875 mm). This thread will also at microphone stands use.

Tripod screw

The tripod screw connects to the camera through a hole in the tripod head with the tripod. It has a knurled grip an enlarged screw head for manual fitting. The tripod screw can be fixedly connected to the tripod. It can also screws and tap for 1/4 "and 3/ 8" Whitworth threads are used. The diameters and pitches of both thread standards are here the same, only the flank angles vary. He is at UNC - threads 60 ° and 55 ° Whitworth threads.

Film and Video Camera Tripods

Film and Video Camera Tripods (Hereinafter: tripods ) have the task to hold the camera at a certain level and they allow a pan and tilt in any direction. A rotation of the camera in portrait format, often allowing for camera tripods by an additional joint is not provided in video tripods. Used normal tripods which are also used in photography to use, as well as the special dolly tripod, which is mainly used in the film industry to perform stable camera movements.

Construction

Camera Tripods are of three units assembled: three or four stand legs, which are held together by a tripod connection plate, and a swivel head.

Tripod legs

Stand legs consist of a pull-out structure which permits the height adjustment. Here, particular emphasis is placed on stability, torsional vibration and freedom. The first tripod legs are made ​​of lacquered wood. Wooden tripods were up about 40 years ago and initially used mainly steel, later replaced by tubular structures made of aluminum alloy, so that wooden tripods now only have less widespread. Today, most carbon fiber reinforced plastic pipes are used. Stainless steel spikes on the legs provide the necessary stability on the ground. Depending on the soil, there is also ground spiders, spider roll or tripod shoes to protect the soil and to ensure a solid grip. Tripod legs are available in different sizes, allowing the height adjustment of approximately 50 to 200 cm lens height.

Tripod connection

The tripod mount is available in different standards. This allows the mounting of various swivel heads ( regardless of manufacturer ).

In amateur spreads are plates on a central column, as with camera tripods, which is passed through a hole in the tripod mount. Professional tripods are spherical shells. Spherical shells are available in different sizes ( eg, 75 mm, 100 mm, 150 mm diameter ) are available. The spherical shell allows quick and easy alignment of the tripod head in a horizontal position, as it can be swung releasing a Klemmvorichtung in the spherical shell back and forth. This design is particularly important in film and video tripods, since only in a horizontal orientation of the head at its base exactly horizontal panning ( panning ) and vertical tilting ( tilting ) are possible. Plates with center column are taken usually in the field of photo tripods.

One other widespread tripod mount is the Mitchell - port ( engl. Mitchell flat base ) for larger tripod heads or for heavy cameras. Here the orientation in the horizontal plane with the tripod leg height adjustment or an extra screw adjustment element is performed.

Swivel Heads

Swivel heads are mechanical units that allow stored about two axes to tilt the camera and pan. The pivoting heads of film and video tripods are provided in both directions with an attenuation to compensate for the inaccuracy of the human arm, and to impart a dynamic of acceleration and deceleration. This damping can be adjusted, depending on the type of motion, the weight of the camera and the focal length. Pure Photo heads require no damping, as no movements are performed during recording.

It can be distinguished according to the attenuation four types of swivel heads:

Fluid head

Fluid heads presses a viscous fluid through metal chambers. The resulting friction dampens the movements.

Friction head

Friktionsköpfe use the friction surface side by side stacked, grease lubricated metal discs.

Centrifugal head

The spinning head is a means of centrifugal mechanically stabilized head, which is now only of historical importance. 1958, however, aroused Wendelin Sachtler with this invention a stir: About transmissions were driven here by the pivotal movement of the head in both directions flywheels with a relatively high speed, which (similar reversed in toy cars with flywheel drive ) caused an attenuation of the original swivel head movement.

Socket head

Crank heads move the camera by two mechanical gears.

The head is moved by two hand cranks where the crank acts like a flywheel itself. There are two kinds of crank heads which differ by the power transmission to the camera. It can be done via screw drive or belt ( on older models with wire rope ).

Quick Release Plate

Most tripod heads are equipped with a mounting kit for a quick release plate, with the rapidly mounted the camera to the quick release plate is attached to the head and can be taken away again. In the field of video tripods, the recordings are often designed so that a shift of the quick release plate as seen by the camera is possible to balance the (possibly varying depending on the setup ) camera weight.

Load

An important property of the pivot heads is the maximum load. It will be built up to 50 kg tripod heads for camera systems (ie camera & lens ) from 500 g. Rule of thumb is to use the tripod head having the next higher level of the load, when the camera system itself weighs.

Comments

The most common heads are the fluid and Friktionsköpfe that are manufactured in all sizes and are sometimes confused by the similarity. It is possible to attach swivel heads not only on tripod legs, but on camera dolly ( dolly), on special racks such as car mounts, helicopter fittings or camera cranes with the corresponding tripod connection.

Copy stands

Copy stands are used for reproduction of documents of all kinds This is, for example, documents, pictures, slides, or smaller items. A copy stand consists of a base plate, a tripod column and the stand arm. Usually the height adjustment with a crank is possible. Shadow-free lighting at least four lamps are additionally required. In conjunction with a light panel lighting is also possible from below.

In addition to the classic design of the copy stands with a stable column designated as rods unit in German-speaking special stands by the camera manufacturers for the particular camera model were adapted, manufactured. They consist of a retaining plate and four adjustable length rods. The mounting plate is attached to the filter version for SLR cameras in rangefinder cameras it is mounted between the lens and camera. For rangefinder cameras so that a solid extract extension is provided at the same time. The rods carry markings for DIN formats to allow fixed magnifications for reenlargement. Before the spread of photocopying and digitization, this was the only practical option, Reference books and incunabula to reproduce in libraries. The rods are lightweight and small and much easier to transport than the conventional copy stands.

Differentiation areas

Tripod Legs: number and Materials: There are monopods, tripods and four-legged tripods. Common materials are wood, aluminum, and reinforced with carbon or basalt fibers plastics.

As a center pillar and center pillar crank movable center column are used.

Ball head as a ball joint head ( also short ball head ), a 2 -way Panhead ( cinema tilt head ), be designed as a 3-way pan head or pan head.

Tripod heads are often molded to save weight made ​​from magnesium alloys, but also made from plastic or die-cast aluminum.