Focal Length

Focal length is the basic description of a photographic lens. The focal length tells us the angle of view—how much of the scene will be captured—and the magnification—how large individual elements will be. The longer the focal length, the narrower the angle of the photo will be and the higher the magnification. The shorter the focal length, the wider the angle of the photo will be and the lower the magnification.

Focal length is how far in/out the lens on the camera is zoomed. It essentially  crops part of an image out so it isn’t in your final product. Below is a table I found of different ways you can use focal length and what length best suits what environment/style of photography.

What is and how do we Focus?

An image that is completely sharp is said to be in-focus. An image that’s completely blurry is said to be unfocused. In order for a camera to create a focused image, it takes light and runs it through a lens, concentrating the rays on the image sensor inside. The size of the hole the light travels through (the aperture) determines how focused those rays are once they hit the sensor. Smaller holes do a better job of focusing light than larger holes. The focus can be changed automatically or manually depending on how the settings are set on the camera.

There are a lot of situations where you don’t really want the entire image to be in focus. Backgrounds tend to get in the way, and they will distract the viewer from the point you are trying to make. Portraits, look a lot better when the background is somewhat out of focus as well as macro photos too.

Furthermore, it is simply harder to draw attention to things that don’t stand out on their own. When we focus our eyes, we do something similar. You might not notice it, but everything else in your peripheral vision appears a little more hazy or blury. Most of the time, only one part of photographers images should be truly sharp and the rest a little fuzzy so the sharp part stands out.

Range of focus points

There are a variety of different focus points in which can be used in photography. On a DSLR camera you can manually select your focus point using the grid in the image below. each rectangular square represents a focus point and by selecting a certain focus point your camera will mainly concentrate on focusing that area of the picture.

These images clearly show a range of focus points and how the different focus points have an effect on the image, whether it just draws your eyes to a different point in the photograph or tells a different story.

Using focus points i decided to experiment myself. These pictures were taken at the exact same angle and zoom length. The only difference is the focus point.

How do you achieve Bokeh Photography?

To achieve the bokeh affect you will have to Set your camera to Aperture Priority mode. Select the smallest possible aperture (f) number for your lens. Switch your camera to manual focus and manually adjust the focus ensure the whole image is completely out of focus. Zoom your lens to wherever best will suit the photograph.

Examples of Bokeh Photography

Definiton

In photography the distance between the nearest and the furthest objects giving a focused image.

What is Depth of Field

Depth of field is the zone of acceptable sharpness within a photo that will appear in focus. This zone will vary from photo to photo. Some images may have very small zones of focus which is called shallow depth of field. Others may have a very large zone of focus which is called deep depth of field. Three main factors that will affect how you control the depth of field of your images are aperture, distance from the subject to the camera, and focal length of the lens on your camera

Depth of field (DOF), also called focus range or effective focus range, is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image.  A camera can only focus its lens at a single point, but there will be an area that stretches in front of and behind this focus point that still appears sharp. This zone is known as the depth of field. It’s not a fixed distance, it changes in size and can be described as either shallow or deep.

Because depth of field has an impact on both the aesthetic and technical quality of a picture. Sometimes you’ll want to use an extensive depth of field in order to keep everything sharp.

A classic example is when you’re photographing a landscape, where generally the most desirable outcome is to capture detail from the foreground to the horizon.

Other times, a shallow depth of field will be preferable. It enables you to blur background and foreground details, causing distractions to melt away and allowing you to direct viewers to the focal point in a picture.

Aperture

Aperture refers to the access given to light from the lens to the camera sensors. The size of your aperture controls the amount of light entering the lens of the camera. Using aperture is the simplest way to control your depth of field as you set up your shot. The lower the f-number, the smaller your depth of field, meaning less of the image will be in focus. On the other hand, the higher the f-number the larger the depth of field should be and most of the picture will be in focus.

Distance from your subject

The closer your subject is to the camera, the shallower your depth of field becomes. Therefore, moving further away from your subject will deepen your depth of field.

What is shutter speed?

In photography, shutter speed or exposure time is the length of time when the digital sensor inside the camera is exposed to light, also when a camera’s shutter is open when taking a photograph. A longer shutter speed will allow more light into the picture, which is better for dark subjects or places and short shutter speeds let in minimal amount of light however can capture fast paced moving subjects.

This simple diagram clearly shows  how shutter speed works using a tripod. A fast shutter speed, for example 1/500 in this case is able to capture the man running in high quality detail. Whereas the slower shutter speed of 1/2 of a second cannot capture the man running quick enough therefore leaves a motion blur within the photo.

Clearly in the image above there is a clear difference when using different lengths of shutter speeds. I believe that the longer shutter speed photographs are extremely unique and can produce very interesting images like the water in the image above which looks silky. Following this, I intend to experiment shutter speed by using mainly slow shutter speeds to create these unrealistic and unique pictures.

Below are some basic images in which I took around school exploring shutter speed.

Robert Frank (born November 9, 1924) is a Swiss-American photographer and documentary film maker. His most notable work, the 1958 book titled The Americans. His style of work is classed as photo journalism and documentary/street photography.

Technical

The first thing which caught my eye when observing this picture was the clear use of the rule of thirds. The bus itself create natural lines almost along the horizontal lines when following the rule of thirds. I believe this helps the viewer the see how the picture is made up of several portrait pictures. There is a large tonal range within this picture, with lighter tones towards the top and darker tones towards the bottom. The tonal range can also be seen within the skin tone of the people on the bus, from the left hand side a white man is presented and on the right hand side we are presented with a black person. We can clearly identify that Robert Frank would have used a fast shutter speed in order to take this photograph. This is because the picture is of a moving subject and would require a fast shutter speed to prevent a blur in the image. With a fast shutter speed he was able to capture a sharp photo.There is also multiple textures inside of this image, for example there is the texture of the trolley at the bottom of the image. The blots on the trolley also add another texture to the image.  Moreover, there is the texture of the windows at the top of the image, these look smooth.

Visual

This image is split into 3 main sections, the top middle and bottom. The middle part is the main focus which contains the main subjects of the people. Where as the top and bottom contain some interesting textures and reflections but this is not what stands out and catches the viewers eye immediately. There is a definite contrast within this image, with the black and whites exaggerated. There is a clear contrast between the white poles/bars separating the people and the rest of the bus, perhaps influencing us that they are a main factor of the image. This photo has been captured in natural light which is expressed in the reflections at the top of the image. I think that the use of the picture being in black and white emphasizes the different races.

Contextual

This image taken by Robert Franks was captured in the 1950’s. This image was also taken in America, New Orleans. At this time period,  America experienced marked economic growth – with an increase in manufacturing and home construction among a post–World War II economic expansion. At this time period it was uncommon for photographers to tackle the issue of racism which is a key theme portrayed within this photo. The time period when this photo was taken was a time of racism and prejudice. Although the photo may have been an ‘accident’ as Robert Frank himself said, it may have been a powerful and strongly influential picture to help the problem with racism.

Conceptual

It looks as if the different races are separated from each other. The white man is at the front of the trolley while the rest are sat behind him. This can connote the fact that at this time people like that where protected by society and had more ‘privilege’. The different facial expressions of the different people can say quite a lot about the image. They all have the same serious look about them. This can represent the lives of these people. The layout of the characters in the image also represents the different classes, for example the man at the front could be a higher class than the one at the back however we do not know this it is just interpretation. The white bars can again also show the separation between the different classes.

What is ISO 

ISO is the level of sensitivity of your camera to available light. The lower the ISO number, the less sensitive it is to the light, while a higher ISO number increases the sensitivity of your camera. The component within your camera that can change sensitivity is called “image sensor.” With increased sensitivity, your camera sensor can capture images in low-light environments without having to use a flash. But higher sensitivity poses a problem as it it adds grain or “noise” to the pictures.

The difference in this image is clear – the image on the right hand side at ISO 3200 has a lot more noise in it, than the one on the left at ISO 200.

Low ISO Speed

High ISO speed