Category: Course Activities (Page 7 of 10)

Bees

Photo credits: Top, left to right: Tina Gunasekera, Julian Georgi, Jabez Brisueno

Bottom: Fawziah Akhter, Brianna Brand, Alan Castillo

Light Quality

Light is either direct or diffused.

Direct light: the light strikes the subject from one angle and creates sharp shadows. Sunlight is an example of direct light.

Diffused Light: the light hits the subject from many angles and creates soft shadows. The light is diffused on an overcast day or in the shade.

Photo credits: Left-Joel Barbeco, right-Alan Castillo

Measuring the Amount of Light

Exposure is the amount of light that comes into the camera to create the photograph.

Exposure is made up of three components:

1. ISO-Sensitivity to light.
2. Shutter Speed-the length of time that the camera’s shutter is open during the exposure.
3. Aperture-how wide the cameras lens opens to allow the light to come in.
   

All three are measured in stops. Each full stop of light represents that the amount of light has doubled or reduced by 1/2.

How your Camera Meter Works

Acronym: TTL – Through the Lens

The meter in your camera is a reflected-light meter.

A reflected light meter averages the tones in the scene and selects the aperture and shutter speed values that will make the whole scene medium gray.

Watch from :45 to 1:34 for an explanation of how your camera meter works.

Challenges

There are certain predictable situations that will fool your meter.

1. Backlight – a common example is a person against a window or against the sky. Add exposure to get the right exposure for the main subject and allow the background to be overexposed.

2. Landscapes with sky. The sky is brighter than the ground and to get a good exposure of the land portion of your photo, often you need to over expose the sky.

3. Snow

How to control exposure

With a camera: Use Exposure Compensation set to plus to increase the light and set to minus to decrease the light.

Exposure Compensation-a way to force the camera to make an exposure either lighter or darker than the meter reading. Good for backlight or extremes of light and dark.

With a cameraphone: Touch the area where the main subject is and then drag the little sun icon up or down to increase or decrease the overall exposure.

Using Exposure for Creative Effect

Sometimes, you don’t want the tones in your image to average out to a medium gray. You want to tones to be low key-mostly dark or high key-mostly light.

Lab Exercises

Exposure and Meter Challenges

Homework Due Next Class

Midterm Project

Review for Quiz 1: Composition, shutter Speed, Motion Capture, Aperture, Depth of Field, Perspective, Exposure, How the Meter works, Exposure Challenges

Upcoming Schedule

October 4 – Quiz 1, Lightroom, Midterm Project Support

Oct 11 – Midterm Project Presentations

Oct 18 – Outdoor portraits-Brooklyn Bridge Park

Aperture

Aperture is the size of the opening that allows light to hit the camera’s sensor when the photograph is taken. 

1. Aperture values are expressed in numbers called f-stops. A smaller f-stop number means more light is coming into the camera and will create shallow depth of field. A larger f-stop number will let less light into the camera and create extensive depth of field.
2. The full stops for aperture are: F2, f28, f4, f5.6, f8, f11, f16, f22, f3

Depth of Field

Depth of Field-The distance between the nearest and farthest points that appear in acceptably sharp focus in a photograph. Depth of field can be shallow or extensive. While the term includes the word depth, depth of field refers to focus.

Shallow Depth of Field

Shallow depth of field is commonly used in portrait photography to separate the subject from the background and in food photography.

Extensive Depth of Field

Extensive depth of field is often used in landscape photography and photojournalism.

The depiction of space

Perspective-the representation of a 3-dimensional space on a 2-dimensional surface by converging lines, diminishing scale and/or atmospheric perspective.

Sometimes photos combine perspective and shallow depth of field.

How to control depth of field (with a camera)

These four factors control depth of field:

• lens aperture 
• focal length
• camera-to-subject distance
• sensor size.

Focal Length  is the distance from where the light converges in the lens to the sensor. If it is a short distance then the lens is a wide angle lens and shows a lot of the scene. If it is a long distance, the lens is a telephoto lens and it magnifies the scene. Wide angle lenses create extensive depth of field while telephoto lenses create shallow depth of field.

Camera-to-subject distance is how far the subject is from the camera. If everything is far from the camera, it is easier to achieve extensive depth of field. If the main subject is very close to the camera and the background elements are far from the camera, it is easier to achieve shallow depth of field.

It is the small size of the sensor that makes cameraphones so good at achieving extensive depth of field. It is also the main reason it is so hard to get your cameraphone to achieve shallow depth of field.Sensor size-the smaller the sensor the easier it is to achieve extensive depth of field. Bigger sensors allow for shallow depth of field.

 Bokeh-Bokeh comes from the Japanese word boke (ボケ), which means “blur” or “haze”, or boke-aji, the “blur quality.” Bokeh is pronounced BOH-Kə or BOH-kay. 

 — From http://www.nikonusa.com/en/learn-and-explore/article/h0ndz86v/bokeh-for-beginners.html

Lab Exercises

Lab 4: Space and Focus

Homework

HW 4: Space and Focus