Text of Recor presentation on slr & digital cameras
1. CAMERAS HOW TO USE A DIGITAL AND SLR CAMERA AND THE DIFFERENCES BETWEEN THEM Konica Minolta Dynax-Maxxum 5D Digital SLR Camera Nikon Coolpix digital camera
2. INTRODUCTION THERE ARE LOTS DIFFERENT STYLES OF PHOTOGRAPHY AND TYPES OF PICTURES YOU CAN TAKE. Fashion photography Landscape photography Photo Journalism paparazzi Art created photography Wedding photography Still life photography Travel photography portraiture
3. So what are cameras? A camera is a device that records/stores images. These images may be still photographs or moving images such as videos or movies. cameras generally consist of an enclosed hollow shape with an opening at one end for light to enter, and a recording or viewing surface for capturing the light at the other end. A majority of cameras have a lens positioned in front of the camera's opening to gather the incoming light and focus all or part of the image on the recording surface. still cameras take one photo each time the shutter button is pressed. Cameras can act as time capsules that record the information and personal response of options and themes that take place in life. A lot of photographers choose to use cameras to explore their experiences.
4. EXPOSURE Exposure means how much light the film or sensor is exposed to when the lense is open. If the exposure it too high the image will wash out or if it is too low the image will be dark. In modern cameras this is usually default and produces really good pictures in the right environments. When no artificial light is used, in weather and landscape photography for example, the exposure is determined by aperture, shutter speed and ISO and each affect each other.
5. ISO ISO is the element you can adjust in the film. It stands for International Standardisation Organisation and their film ratings are used to indicate the relative amount of light needed to give proper exposure and determines how quickly a film or sensor will respond to a certain amount of light. The most common films are at ISO 100 or 200. ISO 100 is normal films but ISO 200 will give the same exposure with half the light which enables you to shoot in lower light or with a smaller aperture or shutter speed. The lower the ISO the less sensitive. The most range is from 50 to 3200 but it depends on the model or film. The ISO speeds most common are: ISO 100 or 200- use in high light outside with sunny conditions ISO 400 to 800- use in medium light or a cloudy day to evening ISO 1600- use in low light or night time
6. DEPTH OF FIELD Depth of field is the how much of the objects in the image are in focus. Lenses only focus on one particular distance but changing the depth of field allows the photographer to emphasise certain elements and isolate them in portraits for example and make everything in the foreground and distance sharp in landscape photography. You can alter the depth of field through; The aperture, the smaller the aperture the greater the depth of field, The focus point, the further you focus into the distance the greater the depth of field in relation to close ups, The lense, the shorter the focal length of the lense the larger the depth of field. Also the wider the lense the greater the field of view but the closer you need to be to the subject. The wider lense is less magnified than the smaller one but the background appears sharper. The type of camera also effects the depth of field. If the sensor is small the depth of field will be greater than larger sensors which are shallower but larger sensors offer the photographer greater control. Aperture size and shutter speed affect an images sharpness and definition. With a small aperture the effects of diffraction ( see aperture an f-stop for definition) outweigh the larger depth of field causing a reduction and this small aperture increases the shutter speed which has a negative effect unless you are using a tripod which limits this but is not always practical. There is also depth of focus which should not be confused with depth of field as they are two separate things. Depth of focus is how far the sensor can be moved away from the point of focus and still produce a sharp image.
7. SHUTTER SPEED The shutter speed is how quickly the shutter opens and closes and it determines the amount of time the light has to reach the film or sensor. The shutter speed options depend on the type of camera and can be fractions of a second or seconds. If too much light enters when the shutter is open for too long your image will become over exposed and pale or white. with day time photography shutter speeds are usually high. Shutter speed on manual older cameras were adjusted using dials on the top or front but now are adjusted electronically and now have longer shutter speed options. The faster the shutter speed the less motion so the clearer more focused the picture. high= clear and sharp mid= middle Low=blurry Altering the shutter speed will also directly alter the Aperture settings on digital and SLR cameras
8. APERTURE AND F-STOP Aperture is controlled by the lens and is the amount of light that it lets through the shutter. It also effects the focus and depth of the picture. At smaller apertures(high f-stops) the lense acts as a pin-hole and everything will appear sharp whereas with larger apertures everything except objects quite close to the lense will be un-sharp. So although you usually want as large a aperture as possible it depends on the type of photography. Diffraction is noticeable at smaller apertures also. Diffraction is caused by the wave nature of light and how its behaviour changes when it passes through an aperture or against the subject and can affect the sharpness and definition of the image. Each F-stop setting is half the size of the setting before it and double the size of the one after it. The higher the f number the smaller the aperture setting. Wider aperture setting are commonly used for close up and portrait shots.
9. THE EFFECTS OF CHANGING THESE EXPOSURE SETTINGS As mentioned before exposure can be controlled by changing the shutter speed, aperture and ISO and they all affect each other and do not always have positive effects on the quality of the image. Large apertures cause visible lens errors to the photo such as aberration (deviation from what is expected) and un-sharpness. A tip is to use 2 or 3 stops smaller than wide if you have enough light to reduce this. Small apertures also cause un-sharpness due to diffraction of light so should be avoided if possible. (remember aperture determines depth of focus which is not such an issue in weather photography for example but it is in macro photography) Long exposure times (low shutter speeds) need tripods and will blur moving subjects however short exposure times are not always possible due to low light. low ISO numbers require longer exposure which is not always possible and high ISO numbers suffer from coarse film grain in film and thermal noise with digital sensors. When choosing setting it depends on what you are photographing, in what style and how much light you have. In some styles or lighting one aspect mat be more important than another and as a photographer it takes practice to know what settings are needed, although several combinations will produce the same effects.
10. VEIWFINDERS,SHUTTER FLASH AND LIGHT SENSORS Viewfinders- a viewfinder is the window you look through to compose a scene.There are four types of common viewfinders. Optical viewfinders, they are small, hard to use and often inaccurate as they are placed on top of the lense and what you see through it isnt necessarily what is projected onto the sensor. LCD screens, show the image the sensor pics up in real time. It shortens battery life and it may be difficult to frame accurately in bright sunlight. (SLR cameras only show the image after it is taken) Optical viewfinders, show what will be projected onto the sensor using mirrors. Saves battery life and allows you to look directly through the lense so more accuracy. Electronic viewfinders, act like LCD screens and show what is being projected in real time which allows you to frame more accurately especially in bright sunlight. Shutter flash- when the shutter release button is pressed all the way down to take a photo the camera triggers the flash which illuminates the scene. This canbe controlled by the different settings. On manual mode (M) the flash operates at full capacity and it is up to the photographer to adjust all the exposure settings according to this, in automatic mode (A)a flash sensor on the camera measures the amount of light and sets the flash intensity according to this and in TTL mode (through-the-lens) the flash sensor is inside the camera body and can tell the flash what aperture and ISO is being used and adjust accordingly though this is not available on all camera models. Light sensors- we already briefly covered this in shutter flash but light sensors monitor the amount of light around and being produced and also verify colour information. Light sensors can be inside and outside ofthe camera.
11. SLR: Single Lens Reflex camera A single-lens reflex (SLR) camera is a camera that typically uses a semi automatic moving mirror system that permits the photographer to see exactly what will be captured by the film or digital imaging system (after a very small delay). They are the most expensive of all digital cameras because they can take higher quality images and have various adjustab