Hi, it's Kevin from the photography playground. Welcome back. In this lecture we're gonna lay the foundation for controlling your camera. To gain the skills to control your smartphone camera, it's necessary to know something about the basic principles of photography. Photography is based on one simple principle it's light. Without light, there is no photograph.

The word photography comes from ancient Greek and it means to draw with light. The light of the world falls on the light sensitive medium the sensor and creates a little world of its own a photo, I still think it's magical. What we need to know and control is the amount of light that falls on the sensor the exposure of the photo, we have three tools to control the amount of light that falls on the sensor and together we call them the exposure triangle. The exposure triangle consists of shutter speed, aperture and ISO value. shutter speed and aperture control the amount of light that falls on the sensor. ISO value controls the light sensitivity of the sensor.

They also control other aspects in the photograph, we'll discuss both aspects of these three values starting with shutter speed. The shutter speed is the time the light falls on the center, it is controlled by the shutter. The longer the shutter is open, the more light falls on the sensor. In general, you can say when there is a lot of light available, you will use a fast shutter speed. When there is a little light available, you will use a slow shutter speed. The shutter speed also influences the way the movement is captured in a photo.

The faster or shorter the shutter speed the more the movement becomes frozen and the slower or longer the shutter speed, the more the movement becomes blurry. shutter speed is measured in seconds or more precisely, in hundredths of a second the shutter speed all the way on the left is a fast shutter speed of one five hundredths of a second, resulting in a frozen moving cyclist. The shutter speed all the way on the right is a slow shutter speed of one third of a second resulting in a blurry moving cyclist. In general, shutter speeds from one 200 and 50th of a second and faster will result in sharper images. This photo was taken with a shutter speed of one 4003 hundredths of a second and it's very sharp and detailed. Even the propellers of the plane are clearly visible.

This photo was taken with a shutter speed of one 30th of a second resulting in a blurry running boy. The second value is the aperture. The aperture is the size of the opening through which the light falls, the bigger the opening, the more light falls through. Unfortunately, this is a value you cannot control in this smartphone camera because the aperture is fixed. But you do need to know a little bit about aperture because of this valuate controls which is the depth of field, the depth of field is the range of sharpness in the image from front to back. The images on the left have a narrow depth of field the house in the background is blurry while the man in the foreground is sharp.

The images on the right have a large depth of field both the man and the house are sharp. a smartphone camera has a large depth of field as you can see in this photo, demand plane and the horizon are all in focus. The only way to accomplish it narrow depth of field in smartphone photography is when you move very close to the subject and the background as far as you can see here the depth of field is more narrow. The glass is in focus and the background is blurry. The third value is the eyes Oh, it controls the light sensitivity of the sensor. When there is a lot of light you use a low ISO and when there is a little light you use a high ISO it also affects the visibility you pixels in general sharpness of the photograph.

The lower the ISO, the more sharp and detailed the image will be. The higher the ISO, the more pixelated it will become. The image all the way on the left represents a low ISO and it is sharp and detailed. The image all the way on the right represents a high ISO as high as most phone cameras can go. And you can clearly see the pixels resulting in a general fuzziness. The ISO in this image is 25 and you can see it has an overall sharpness editor detailed the ISO in this photo is 2000 you can clearly see the pixels and it has a general fuzziness.

Now let's bring them together. At the top of the triangle we have shutter speed. shutter speed is the time the light falls on the sensor and it controls the way movement is captured. aperture is the size of the opening and it is fixed in a smartphone camera. It also controls the depth of field on the right is The ISO value indicates the light sensitivity of the sensor. It also controls the general sharpness of the image.

A fast shutter speed freezes a moving subject. A slow shutter speed blurs a moving subject. Depth of Field is usually very large in smartphone photography. It can become narrow when you move very close to the subject. Hello eyes Oh, results in sharp and detailed photos. A high ISO results in fuzzy and pixelated images.

To get a deeper understanding of the exposure triangle, I advise you to come back to this lecture every once in a while and watch it again because it might take a little while to sink in. Also check the cheat sheet regularly. They can be very helpful. See you in the next lecture. And in the meantime, happy photographing