Photography techniques

Apperture 

The camera lens has a hole in it which light travels through and into the camera body, You can shrink or enlarge the size of the aperture to allow more or less light to reach your camera sensor.

The aperture works like an iris :

Bigger for more light & Smaller for less light 

exposure is the brightness of the image, as aperture controls the amount of light it affects the exposure as this is brightness of the image.

Overexposed = too much light 

underexposed = too little light 

Large aperture = light 

small aperture = dark

depth of field is about the focus points in your image, the shallower the depth of field means only part of the image is in focus however a deep depth of fields means the whole image is in focus.

portrait photography normally uses shallow depth of field however landscape photographers need deep depth of field.

Large aperture = large blur

Small aperture = small/ no blur

aperture holes are known as f/stops and are expressed as fractions, and the smaller the fraction the smaller the hole

f/2.8 = big , f/16 = small

DEPTH OF FIELD

Depth of field is about the focus points in your image, the shallower the depth of field means only part of the image is in focus however a deep depth of fields means the whole image is in focus.

APPERTURE 

The camera lens has a hole in it which light travels through and into the camera body, You can shrink or enlarge the size of the aperture to allow more or less light to reach your camera sensor.

SHUTTERSPEED

Shutter speed changes the brightness of you photo (aperture)

Create dramatic effects by either freezing or blurring motion.

The length of time your camera shutter is open, exposing light onto the photo.

The first big effect of shutter speed is motion blur. If your shutter speed is open long or slow moving subjects will appear blurred.

It demonstrates 

• speed 
• aesthetic contrast

The effect is used often in car/motorbike adverts where a sense of speed is important.

Light Trail

Shutter speed can also be used to freeze motion, if you use a very fast shutter speed you can capture really quick objects such as cars or birds in flight 

If photographing water you can create hanging droplets as if frozen.

Measuring shutter speed

shutter speeds are measured in a fractions when they are under as second, for example 1/4 means a quarter of a second ,

long shutter speeds are typically above 1 second and you will need tripods to get sharp images 

fast shutter speeds are typically 1/4000.

Blurry = long shutter speed

Sharp = fast shutter speed

Exposure and shutter speed 

If the image is taken with a quick shutter speed the image is darker due to not a lot of light being able to enter due to the quickness of the lens, the longer the shutter speed the lighter the image due to more light being able to enter.

If we had a camera set on a slow/long shutter speed, its set on 1/80 shutter speed and it will let in a lot of light when we take the photo

How could we use aperture to darken the image?

To darken the image we would need a high f/stop number e.g f/22 this would make a small aperture and let less light in so even though the lens will be open for an unusually long time the f/stop will ensure that the image is still dark.

Controlling the shutter speed 

By setting the camera to shutter priority mode you choose the shutter speed and the camera automatically selects the aperture. on your camera this is either the S or the TV button.

By setting the camera to manual mode you can choose both the shutter speed and the aperture manually.

ISO is part of the exposure triangle, this means its linked to shutter speed and aperture,

On DIGITAL cameras, ISO brightens or darkens the image

As you increase your ISO number, your photos will grow brighter.

When you double your ISO, you double your brightness.

ISO values/ISO speeds that you can use, A common set is;

ISO 100     LOW

ISO 200

ISO 400

ISO 800

ISO 1600

ISO 3200

ISO 6400     HIGH

Raising ISO has consequences however a photo taken at too high of an ISO will show a lot of grain, also known as noise 

Your lowest ISO on your camera is a base ISO, this is important as it can give your potentially the best image quality.

You should always try and stick to the base ISO to get the highest image quality with minimal noise.

When you are fighting against motion blur and you will need to between a sharp photo at a high ISO, or a blurry photo at a low ISO.

If you use slow shutter speed or wide aperture to brighten a photo when photographing a fast moving object will be blurry. YOU HAVE TO RAISE THE ISO