George Pratt

Lighting

Light is the "raw material" for creating visual images. Everything related to vision is related to light. Whether the medium is still photography, motion film, video or computer-generated images, light forms the basis of everything you see. It is important to think of lighting not as something extra which is added in some situations, but as a fundamental part of all visual media production. The key to any good video is in the lighting. Good lighting can make a cheap camera look good and bad lighting can make a pricy camera look bad.

If you are able to shoot video near a window or outside on a nice day, then position your subject one of two ways; either shoot them with the light shining directly in their face (if they can be comfortable and don’t feel the need to squint too much) or at an angle so that one side is hot and one side is not. The sun has a full spectrum of light and it renders colours well. Try not to shoot at noon, because the shadows come from above and are hard avoid. Early morning and afternoon means the light is softer, has a more golden tone, and fills your subject better.

Lights with stands can be plugged into the wall and provide brighter light over a larger area. Now you can move your camera and not upset the lighting. Your subject and his or her background can now become part of your story. When you set up a light and stand, place it slightly to the left or right of your subject's face to create a gentle shadow on one side. Make sure you are careful to isolate your light sources, i.e. close or open the shades and turn the office lights on or off. When you mix light, your primary source has to be the brightest.

Focus

Due to the optical properties of photographic lenses, only objects within a limited range of distances from the camera will be reproduced clearly. The process of adjusting this range is known as changing the camera's focus. There are various ways of focusing a camera accurately. The simplest cameras have fixed focus and use a small aperture and wide-angle lens to ensure that everything within a certain range of distance from the lens, usually around 3 metres (10 ft) to infinity, is in reasonable focus. Fixed focus cameras are usually inexpensive types, such as single-use cameras. The camera can also have a limited focusing range or scale-focus that is indicated on the camera body. The user will guess or calculate the distance to the subject and adjust the focus accordingly. On some cameras this is indicated by symbols (head-and-shoulders; two people standing upright; one tree; mountains).

Some cameras have post focusing. Post focusing means take the pictures first and then focusing later at the personal computer. The camera uses many tiny lenses on the sensor to capture light from every camera angle of a scene and is called plenoptics technology. A current plenoptic camera design has 40,000 lenses working together to grab the optimal picture.

Depth of field

In optics, particularly as it relates to film and photography, depth of field (DOF) is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image. Although a lens can precisely focus at only one distance at a time, the decrease in sharpness is gradual on each side of the focused distance, so that within the DOF, the unsharpness is imperceptible under normal viewing conditions.

George Pratt

Colour Balance

In photography and image processing, colour balance is the global adjustment of the intensities of the colours (typically red, green, and blue primary colours). An important goal of this adjustment is to render specific colours – particularly neutral colours – correctly; hence, the general method is sometimes called grey balance, neutral balance, or white balance. Colour balance changes the overall mixture of colours in an image and is used for colour correction; generalized versions of colour balance are used to get colours other than neutrals to also appear correct or pleasing.

The colour balance operations in popular image editing applications usually operate directly on the red, green, and blue channel pixel values, without respect to any colour sensing or reproduction model. In shooting film, colour balance is typically achieved by using colour correction filters over the lights or on the camera lens.

Exposure

Exposure is the amount of light allowed to fall on each area unit of a photographic medium (photographic film or image sensor) during the process of taking a photograph.

In photographic jargon, an exposure generally refers to a single shutter cycle. For example: a long exposure refers to a single, protracted shutter cycle to capture enough low-intensity light, whereas a multiple exposure involves a series of relatively brief shutter cycles; effectively layering a series of photographs in one image. For the same film speed, the accumulated photometric exposure should be similar in both cases.

Camera Angles

The camera angle marks the specific location at which a movie camera or video camera is placed to take a shot. A scene may be shot from several camera angles simultaneously. This will give a different experience and sometimes emotion. The different camera angles will have different effects on the viewer and how they perceive the scene that is shot. There are a few different routes that a camera operator could take to achieve this effect.

Framing

In visual arts including cinematography, framing is a technique used to focus the viewer's attention upon the subject.

Framing can make an image more aesthetically pleasing and keep the viewer's focus on the framed object(s). It can also be used as a repoussoir, to direct attention back into the scene. It can add depth to an image, and can add interest to the picture when the frame is thematically related to the object being framed.

The frame of an image is determined by many factors, including:

Depth of field - the range of focus within the image White space - the empty space surrounding the subject Colour and lighting Crop