Criteria 2
Be able to use advanced camera techniques creatively
2.1 - Explore the effect of shutter speed on the visual aspect of the photograph
Evidence: Written explanationExplain the effects of using different shutter speeds. Use your own images to illustrate.
The first photograph (ISO 1600 – F/4.5 – 1/1000) shows the water droplets frozen in motion, this is an example of selecting a fast shutter speed. Because of the fast shutter the camera automatically set the aperture to F/4.5 to allow for a wider opening to let more light travel through to the camera’s sensor. This resulted in the background to be out of focus because of the shallow depth of field created. The ISO setting was set to 1600 maximum because I did not want to increase this setting due to the noise it would create within the picture.
In contrast the last photograph (ISO 100 – F29 – 1s) shows the water droplets turned into blurry lines suggesting the movement of water. Because of the slow shutter speed at one second, there was a lot of light traveling through to my camera’s sensor. The camera compensated by narrowing the aperture opening because less light was needed to expose the image. If the Aperture was left at F/4.5 the photograph would be too bright (overexposed) and the image information would be lost. The narrow aperture not only resulted in cutting down on the light information but also created a wider depth of field as the background now is more in focus. The ISO setting automatically changed to its lowest sensitivity setting of one hundred.
Diagram to show fast and slow shutter speed settings suitable for different subject matter.
2.2 - Produce images which demonstrate knowledge of shutter speeds
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| ISO 500 - F/20 - 1.3s |
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| ISO 100 - F/25 - 1.6s |
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| ISO 100 - F/22 - 24s |
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| 1SO 250 - F/29 - 1/200 |
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| ISO 5600 - F/5.0 - 1/500 |
2.3 - Produce images evaluating the functions of the aperture control
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| 1SO 110 - F/5.6 - 1/160 |
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| ISO 560 - F/9 - 1/160 |
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| 1SO 320 - F/20 - 1/100 |
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| ISO 1250 - F/14 - 1/125 |
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| ISO 320 - F18 - 1/100 |
2.5 - Produce images which demonstrate the use of shutter and aperture priority modes
Evidence: 10 images
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| ISO 100 - F/4 - 8s Atmospheric shot of the Goa express playing at the Golden Lion in Todmorden. |
Album Cover Work Sheets
2.4 - Explain the connection between ISO, shutter speed, aperture and exposure values
Evidence: Illustrated reportIntroduction
Exposure is the balancing of light and this is controlled by three camera settings called the aperture, shutter speed and the ISO. When using a digital camera the image information is in the form of pixels which are being exposed to light. The light flows through the lens to the camera’s sensor creating the exposure of an captured image. A combination of the three elements can be used to control or to exaggerate the light. This manipulation of the exposure settings personalises creativity by allowing the photograph to take on a feeling or a mood; or to tell a story by capturing movement by the freezing or blurring the action. By understanding these exposure settings and what effects they have on each other allows me to experiment and take control. I am able to make decisions when compromises have to be made due to the different lighting situations combined with adjusting my exposure controls.
Aperture
The lens aperture regulates the amount of light allowed to pass through to the camera sensor. The size of the opening is called a F/stop. The larger the opening the more light enters the camera and the smaller the opening the less light reaches the sensor. The aperture size depends on the type of lens you use combined with the light available, to the style of photograph you want to create. The larger the F/stop the smaller the opening and the smaller the F/stop the wider the opening.
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| vhsszakel.weebly.com Diagram showing the lens aperture openings and its effects |
The aperture also controls how much of the scene is in focus. This is called the depth of field. The lower the F/stop number the shallower the depth of field where a single area is in focus and the background is blurred out. Lower F/stop settings are ideal for portraiture photography. The higher the F/stop number increases a wider area is in focus and this is ideal for Landscape photography.
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| www.edmundoptic.com Diagram showing the difference between a large and narrow aperture setting and how this effects the depth of field. |
Shutter Speed
The shutter speed controls the duration of time the sensor is exposed to light. The longer the shutter is opened the more light reaches the sensor and this time is represented by fraction of a second to whole seconds. Having control over the shutter speed can freeze moving action and in contrast can introduce blur, bringing a sense of movement to an image. A fast shutter speed is used in sports photography to freeze action (1/500) and slow shutter can be used to introduce more light when the surrounding lighting is poor. In night photography slow shutter speeds can also be used to take creative shots such as when producing light trail (10s).
ISO
The ISO enables the adjustment of the light sensitivity of the image sensor. The ISO value is controlled by numbers which double up each time in value. For example the lower the number such as ISO 100, the lower the sensitivity to light. The higher the number the higher the sensitivity, this is when the image sensor has to work harder to establish an image. The advantage of a lower ISO setting means an overall cleaner image because there is less digital noise, whereas the higher the number such as ISO 3200 introduces lots of noise therefore as less sharper image.
When the lighting is poor selecting an higher ISO number is usually taken as a last resort. This is when the aperture and shutter speed controls have been adjusted to the point where light hitting the sensor can no longer be improved.
Conclusion
The Exposure Value (EV) is a combination of the lens aperture, the shutter speed and the ISO settings. A diagram of the exposure triangle clearly shows the relationship between these three values and the juggling act needed to balance the light hitting the camera sensor.
One decision about one element will make a compromise decision on another. The ideal is to try and get all three exposure values working together. When you increase the exposure by one stop the camera receives twice the level of exposure. Decrease it by one and the exposure level is halved. If the light is bright, I would increase my shutter speed and select a bigger F/stop (depending on the depth of field I wanted to achieve); I would also decrease my ISO to its lowest level of 100. If the lighting is too dark, I would decrease my shutter speed and use a tripod for stabilisation. I would also select a smaller F/stop and increase my ISO value. I have found it difficult obtaining a good exposure when trying to freeze action in dark conditions where I had no other option than to up my ISO levels resulting in a much grainier picture than I would have liked. I also have used the exposure compensation, which helps by taking overexposed or underexposed images by selecting an higher or lower setting than it thinks is right. This is measured in stops and is shown by an indicator scale at the back of my camera.
Exposure values act as a guide because exposure settings to me is subjective, and relates to the type of image you want to communicate to the viewer with.
The shutter speed controls the duration of time the sensor is exposed to light. The longer the shutter is opened the more light reaches the sensor and this time is represented by fraction of a second to whole seconds. Having control over the shutter speed can freeze moving action and in contrast can introduce blur, bringing a sense of movement to an image. A fast shutter speed is used in sports photography to freeze action (1/500) and slow shutter can be used to introduce more light when the surrounding lighting is poor. In night photography slow shutter speeds can also be used to take creative shots such as when producing light trail (10s).
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| snapsnapsnap.photos.com Diagram showing how the shutter speeds are effected by various lighting situations. (Aperture and ISO settings can also be adjusted to compensate) |
ISO
The ISO enables the adjustment of the light sensitivity of the image sensor. The ISO value is controlled by numbers which double up each time in value. For example the lower the number such as ISO 100, the lower the sensitivity to light. The higher the number the higher the sensitivity, this is when the image sensor has to work harder to establish an image. The advantage of a lower ISO setting means an overall cleaner image because there is less digital noise, whereas the higher the number such as ISO 3200 introduces lots of noise therefore as less sharper image.
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| oberphotographytips.wordpress.com |
When the lighting is poor selecting an higher ISO number is usually taken as a last resort. This is when the aperture and shutter speed controls have been adjusted to the point where light hitting the sensor can no longer be improved.
Conclusion
The Exposure Value (EV) is a combination of the lens aperture, the shutter speed and the ISO settings. A diagram of the exposure triangle clearly shows the relationship between these three values and the juggling act needed to balance the light hitting the camera sensor.
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| expertpphotography.com |
One decision about one element will make a compromise decision on another. The ideal is to try and get all three exposure values working together. When you increase the exposure by one stop the camera receives twice the level of exposure. Decrease it by one and the exposure level is halved. If the light is bright, I would increase my shutter speed and select a bigger F/stop (depending on the depth of field I wanted to achieve); I would also decrease my ISO to its lowest level of 100. If the lighting is too dark, I would decrease my shutter speed and use a tripod for stabilisation. I would also select a smaller F/stop and increase my ISO value. I have found it difficult obtaining a good exposure when trying to freeze action in dark conditions where I had no other option than to up my ISO levels resulting in a much grainier picture than I would have liked. I also have used the exposure compensation, which helps by taking overexposed or underexposed images by selecting an higher or lower setting than it thinks is right. This is measured in stops and is shown by an indicator scale at the back of my camera.
Exposure values act as a guide because exposure settings to me is subjective, and relates to the type of image you want to communicate to the viewer with.
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