Saturday 29 September 2012

CAMERA OBSCURA [FILM TECHNOLOGY]





Camera obscura 
[Film Technology] 

For hundreds of years scientists have been able to produce images of real scenes- camera obscura- a large room that acted as a walk-in pin-hole camera -to mid nineteenth century. Modern cameras operate on the basic principle of the camera obscura. Light passing through a tiny hole, or aperture, into an otherwise light-proof box casts an image on the surface opposite the aperture.








CAMERA NOT RUN [FILM TECHNOLOGY]




Camera not run  
[Film Technology] 

 

[1] Camera battery does not produce full voltage on load[poor connections between individual cells].

 

[2] Camera Battery fused or circuit breaker open.

 

[3] Not fully charged [insufficient time, charge current inadequate, mains voltage wrong].

 

[4] Battery not delivering full power due to cold.

 

[5] Battery to camera cable has internal fault.[flex to check.]

 

[6] Battery to camera cable too thin or too long for current.

 

[7] Battery self charge discharged due to excessive heat during storage.

 

[8] Camera buckle switch and camera trip switches not set.

 

[9] Camera not sufficiently winterized for cold conditions.

 

[10] Camera not switched on [more than one switch]

 

[11] Camera seized up or stiff [try inching by hand].

 

[12] Mains power supply voltage or frequency not correct for camera motor [if mains].

 

[13] Poor electric contact somewhere. [uses test meter to test voltage at motor].

 

[14] Camera electronic circuits faulty. [plug in spare boards if available.].








CAMERA MATTE [Film Technology]





Camera matte
[Film Technology] 

Hear a separate silhouette on a graphic is set up in front of a studio camera or a video rostrum camera. This shape is made to correspond with a chosen part of the background picture. The equipment, as before, inserts the part of the subject instead. A foreground vertical plane through which a camera shoots.










CAMERA MASTER [Film Technology]






Camera master
[Film Technology] 

Known as camera stock also. The bulk of raw film stock is loaded into magazines, which are attached to the motion picture camera. After exposure, this now precious commodity, the camera master (camera stock) is unloaded and forwarded to lab. Camera original is the camera master.





CAMERAMAN’S EXERCISE [Film Technology]





Cameraman’s exercise
[Film Technology] 

Here is a number of exercise to help practice your camera work. Do them slowly at first, progressing to faster versions later. Doing several operations simultaneously can test the most experienced cameraman.

[1] Pan across a detailed wall surface, at a very constant speed using a wide lens angle, normal lens angle then narrow lens angles. Now slowly tilt up and tilt down, at a constant rate.

[2] Pan across a scene in which a number of objects at different distances from the camera, focusing on each object in turn as you pan (a) stopping at each, (b) in one continuous pan. Try this at different speeds and distances.

[3] Focus hard on a close foreground subject, then tilt or pan to a different subject, pulling focus(focus pulling) [refocusing] as you do so.

[4] Alter your camera height while keeping the subject exactly in center frame. [Make a small mark in the viewfinder at picture centre.] Go from maximum to maximum height at different speeds. Use closer and subjects.

[5] Move the camera towards a subject [dolly in], continuously refocusing for the sharpest image. Use wide lens angle, normal lens angle and narrow lens angles in turn. Try this for various distances, including table top objects. Now practice dollying out similarly.

[6] Move the camera across the scene [truck] from left to right, then from right to left, focusing whatever comes into shot.[objects at various distances.] Do this again, but holding a static subject in center frame.

[7] Arc around a static subject [keeping it center frame], using wide, normal and narrow lens angles.

[8] Take a close shot at a near by subject, tilt up and quickly zoom in to some distant detail without refocusing, this becomes hit-or-miss. Now refocus to distant subject and try again.

[9] Repeat the effect of [5] by zooming instead.

[10] Put a detailed object nearby, then check the maximum focused distance and available depth of field, using wide, normal and narrow lens angles.

[11] With the [10] set up, use various lens angles, and change the camera distance so that the screen image of the subject remains exactly the same size. [Note how other subjects’ proportions change.






Sunday 23 September 2012

CAMERAMAN’S COMMUNICATION SIGNALS [Film Technology]



Cameraman’s communication signals 
[Film Technology] 

The cameraman can reply to talk back questions and convey simple messages by camera movement in studio floor to the director or CCU operator. 1) No- panning camera right to left. 2) Yes- tilting camera up or down. 3) Having Problem-A circular movement or weaving the camera and or zoom jerks shows he has a problem. 4) Focussing Problem- Rapid in/out focusing shows that he can not focus sharply on his subjects due to limited depth of field.





CAMERA LIGHT [Film Technology]



Camera light 
[Film Technology] 

A lamp attached to the camera to provide local frontal filler light for close-ups, for as a traveling key light. At light weight end of the scale powerful yet small enough to hand held camera light or camera mounted light, particularly useful where mobility is essential. Camera light is a utility light near the lens which serves variously as frontal filler light, to illuminate captions, or to supplement other illumination. Camera lights take several form :  1) single spotlight. 2) spot bar. 3) Broad source. 4) Twin head lamp. 5) Strip light. 6) spot frame circle (garland) of photo flood lights.






CAMERA LENS [Film Technology]




Camera lens 
[Film Technology] 


No lens works perfectly. It is far from simple to grind glass to the ideal shapes, a number of problems arises like chromatic aberrations and the images of object not directly in front of the lens are distorted and light from even a centrally placed object is only moderately well refocused to a point. Many of these defects can be reduced by replacing the simple convex lens by a system consisting of a number of lens elements, made of different type of glass. Such one correcting the faults in the others. A typical camera lens may consists of between four and eight such elements. The lens is as important a part of a camera as the camera body. Lenses are referred to in generic terms as wide-angle, normal, and telephoto. The three terms refer to the focal length of the lens, which is customarily measured in millimetres. Focal length is defined as the distance from the centre of the lens to the image it forms when the lens is set at infinity. In practice, focal length affects the field of view, magnification, and depth of field of a lens.  Cameras used by professional photographers and serious amateur photographers are designed to accept all three lens types inter changeably. In 35-mm photography, lenses with focal lengths from 20 to 35 mm are considered wide-angle lenses. They provide greater depth of field and encompass a larger field of view(or angle)  but provide relatively low magnification. Extreme wide-angle, or fisheye, lenses provide fields of view of 180° or more. A 6-mm fisheye lens made by Nikon has a 220° field of view that produces a circular image on film, rather than the normal rectangular or square image. Lenses with focal lengths of 45 to 55 mm are referred to as normal lenses because they produce an image that approximates the perspective perceived by the human eye. Lenses with longer focal lengths, called telephoto lenses, constrict the field of view and decrease the depth of field while greatly magnifying the image. For a 35-mm camera, lenses with focal lengths of 85 mm or more are considered telephoto. A fourth generic lens type, the zoom lens, is designed to have a variable focal length, which can be adjusted continuously between two fixed limits. Zoom lenses are especially useful in conjunction with single-lens reflex cameras, for which they allow continuous control of image scale.







CAMERA LEFT [Film Technology]





Camera left 
[Film Technology] 

Left side of the cameraman. This is a camera orientation. The description left and right side of a camera is as seen from the rear as seen by cameraman.







CAMERA INFORMATION [Film Technology]





Camera information
[Film Technology] 

The name of production company, name and number of production, name of director, the director of photography and the camera operator, the address of the location or studio, the name of the laboratory to do processing.










CAMERA HEIGHT [Film Technology]




Camera height 
[Film Technology] 

When shooting people, camera height is normally around eye-level, varying according to whether the subjects are standing or sitting[1.2-1.8m/4-5ft standing, 1.1m3.5ft sitting. The normal camera viewpoint is usually around chest height. The height of a camera’s viewpoint can affect a person’s appearance in several ways. Elevated shot or high shots tend to emphasize baldness, plumpness, bosoms, and generally make a person shorter importing and less importing. Depressed camera viewpoint or lower camera viewpoints, on the other hand, tend emphasize noses, particularly large, uptitled or dilated nostrils. Lower shot also draw attention to scrawny necks and heavy jaw lines. A person with a high forehead or receding hair may appear completely bald in the depressed shot.







CAMERA HAND LAMP [Film Technology]





Camera hand lamp 
[Film Technology] 

In video, a lamp affixed to the camera head to provide local illumination close to the camera lens axis. This is used as a `fill light’ for portraiture and as a method of illuminating captions.






CAMERA GAUGE [Film Technology]




Camera gauge 
[Film Technology] 

35 mm film, 16 mm film, Super 16 mm film, 8 mm film, super 8 mm film, 70 mm film. 35 mm is used virtually all films made for theater distribution, as it gives the picture quality for the magnification required. Camera ancillary equipment and cost are highest. 16mm is used for many documentary, Industrial production and TV productions. Smallest equipments advantages in compactness and portability relative to the smaller screen size, high picture quality. Super 8 is occasionally used professionally for low budget work or for news reel items and when a small camera is essential. Limitation in copying, editing and recording.







CAMERA ELEVATION [Film Technology]





Camera elevation
[Film Technology] 


Many shots a camera position higher than ground level is needed, Elevations to various stages of heights will be achieved by the use of rostrum, parallels, camera crane, camera boom arms, scaffolding tower, cherry picker etc.








CAMERA DOLLY [Film Technology]



Camera dolly
[Film Technology] 

Manually operated dollies or powered dollies [power dolly, manual dolly]offer the most sophisticated camera mount or camera wheels, for smooth travel forward and backward form the subject known as tracking whether or not tracks are laid for the dolly wheels. And the most sophisticated camera mounts which can be lowered or raised for high angle camera positions and tracked. Usually found in studios but also on locations for larger budget productions. Shot taken with the camera support mounted on wheels, tracking with subject. See dolly shot and track shot.   Shot taken with the camera support mounted on wheels, tracking with subject.