Camera Lenses

Not knowing each camera lens and what it does was my downfall when I was on work experience with Maxy Bianco so I have researched into them for future reference. A lens may be permanently fixed to a camera, or it may be interchangeable with lenses of different focal lengths, apertures, and other properties. 

The two fundamental parameters of an optical lens are the focal length and the maximum aperture. The lens' focal length determines the magnification of the image projected onto the image plane, and the aperture the light intensity of that image. For a given photographic system the focal length determines the angle of view, short focal lengths giving a wider field of view than longer focal length lenses. A wider aperture, identified by a smaller f-number, allows using a faster shutter speed for the same exposure.

The maximum usable aperture of a lens is specified as the focal ratio or f-number, defined as the lens's focal length divided by the effective aperture (or entrance pupil), a dimensionless number. The lower the f-number, the higher light intensity at the focal plane. Larger apertures (smaller f-numbers) provide a much shallower depth of field than smaller apertures, other conditions being equal.

Focal lengths are usually specified in millimetres (mm), but older lenses might be marked in centimetres (cm) or inches. 

For a given film or sensor size, specified by the length of the diagonal, a lens may be classified as a:

• Normal lens: angle of view of the diagonal about 50° and a focal length approximately equal to the image diagonal.
• Wide-angle lens: angle of view wider than 60° and focal length shorter than normal.
• Long-focus lens: any lens with a focal length longer than the diagonal measure of the film or sensor. Angle of view is narrower. The most common type of long-focus lens is the telephoto lens, a design that uses special optical configurations to make the lens shorter than its focal length.

A side effect of using lenses of different focal lengths is the different distances from which a subject can be framed, resulting in a different perspective. Photographs can be taken of a person stretching out a hand with a wide-angle, a normal lens, and a telephoto, which contain exactly the same image size by changing the distance from the subject. But the perspective will be different. With the wide-angle, the hands will be exaggeratedly large relative to the head. As the focal length increases, the emphasis on the outstretched hand decreases. However, if pictures are taken from the same distance, and enlarged and cropped to contain the same view, the pictures will have identical perspective. A moderate long-focus (telephoto) lens is often recommended for portraiture because the perspective corresponding to the longer shooting distance is considered to look more flattering.

https://media.giphy.com/media/l2JJu55Y2LSvkbBqo/giphy.gif

Aperture, Shutter Speed, and ISO

These three settings are part of what photographers like to call the exposure triangle. ISO is the digital camera sensor’s sensitivity to light. The aperture is a structure in your lens that works much like the iris in our eyes. It opens and close to let more or less light in, and also changes the depth of field, or how many different objects can remain in focus in the shot at the same time. Last is the shutter speed, which controls how much time the camera’s shutter remains open when taking a photo. A longer shutter opening will let in more light but may also cause blurring if any motion occurs while the photo is being taken. This is the same for film making. 

I found this picture explaining what each setting does, which will be very useful.

http://www.boredpanda.com/photography-shutter-speed-aperture-iso-cheat-sheet-chart-fotoblog-hamburg-daniel-peters/

Job Roles - Camera Operator

http://www.snipview.com/q/WTHI-TV

Camera Operators carry out the Director of Photography’s (DoP) and Director’s instructions for shot composition and development. They are usually the first people to use the camera's eyepiece to assess how all the elements of performance, art direction, lighting, composition and camera movement come together to create the cinematic experience.

Camera Operators usually start at the end of pre-production and attend technical recces with other Heads of Department. They work closely with the Director of Photography, Director and Grip, and are responsible for the First Assistant Camera (1st AC), Second Assistant Camera (2nd AC) and the Camera Trainee.

After the Director and DoP have rehearsed and blocked the shots, the Camera Operator and DoP decide where to position the camera and what lenses and supporting equipment to use. Camera Operators liaise with the Grip and other Heads of Department, and keep them informed about how the position and movement of the camera might impact on their workload.

During shooting, Operators are responsible for all aspects of camera operation, enabling the DoP to concentrate intensively on lighting and overall visual style.

Camera Operators make sure the camera and equipment are prepared for the required set-ups and ready for any last-minute changes. They must be able to multi-task and to watch, listen and think on their feet while carrying out complex technical tasks.

They liaise closely with the Director, fine-tuning the exact details of each shot, suggesting creative improvements or alternatives. They supervise the logistics of moving the camera, and oversee the Camera maintenance work carried out by the Focus Puller and the 2nd AC.

Camera Operators work closely with performers, guiding them on what can and cannot be seen by the camera. As DoPs now also operate the camera on smaller films, many Camera Operators specialise in the operation of other precision equipment, such as Remote Heads or Steadicam. Most also work on commercials, promos and television drama.

The DoP or Director often asks for a specific Camera Operator, who in turn makes recommendations about the rest of the camera and grip departments.

The work is physically demanding, and requires high levels of strength and stamina. Hours are long (12-14 hours a day) and some foreign travel may be required, involving long periods spent away from base.

http://creativeskillset.org/job_roles_and_stories/job_roles/3073_camera_operator