Light Painting Photography

Camera Aperture Learning

Aperture

What is Aperture?

     Aperture refers to the opening of a lens's diaphragm through which light passes. It is calibrated in f/stops and is generally written as numbers such as 1.4, 2, 2.8, 4, 5.6, 8, 11 and 16. The lower f/stops give more exposure because they represent the larger apertures, while the higher f/stops give less exposure because they represent smaller apertures. This may seem a little contradictory at first but will become clearer as you take pictures at varying f/stops. Be sure to check your manual first to learn how to set your camera for Aperture Priority, then try experimenting to get comfortable with changing the aperture and recognizing the effects different apertures will have on the end-result image.

How Aperture Affects Depth of Field

Depth of field is defined as "the zone of acceptable sharpness in front of and behind the subject on which the lens is focused." Simply put: how sharp or blurry is the area behind your subject. Here's the equation:

The lower the f/stop—the larger the opening in the lens—the less depth of field—the blurrier the background.

The higher the f/stop—the smaller the opening in the lens—the greater the depth of field—the sharper the background.

How Aperture Affects Shutter Speed

The f/stop also affects shutter speed. Using a low f/stop means more light is entering the lens and therefore the shutter doesn't need to stay open as long to make a correct exposure which translates into a faster shutter speed. Again, the reverse is true: using a high f/stop means that less light is entering the lens and therefore the shutter will need to stay open a little longer which translates into a slower shutter speed.

 

Where to Find the Aperture                          

All lenses have a maximum aperture, and all NIKKOR lenses list the widest possible aperture on the lens barrel. Some zoom lenses will detail something like f/3.5-5.6 on the lens barrel or 1:3.5-5.6 (below right). These numbers, the 3.5 and the 5.6, are referring to the maximum aperture or widest opening the lens can achieve for each end of the zoom range. Some higher end lenses can maintain the largest aperture throughout the entire zoom range, so only one number is detailed (below left).

Choosing the Aperture

Now that we know how to control depth of field, what determines the choices we make in selecting the aperture? We use focus and depth of field to direct attention to what is important in the photograph, and we use lack of focus to minimize distractions that cannot be eliminated from the composition. While there are no rules, there are some guidelines.

For classic portraiture we separate our subject from the surroundings by using "selective focus." Choosing a large aperture (lower f/stop, like f2.8) creates very shallow depth of field with only the subject, or just a portion of the subject, in focus. This helps direct the viewer's attention to the subject.

In a landscape or scenic photograph we usually want to see as much detail as possible from foreground to background; we want to achieve the maximum depth of field by choosing a small aperture (higher f/stop, like f/8 or f/11).

While we can get the maximum or minimum depth of field by working at each end of the aperture range, sometimes we want a more intermediate level of depth of field, limiting focus to a specific range of distances within the overall photograph. One way to do this is to choose a mid-range f/stop, like f/5.6, and shoot a test frame. In image playback, use the magnifying function of the LCD to zoom in and check the depth of field; make adjustments if necessary and re shoot.

The example of the aperture picture

Digital Photography

Pin Hole Camera

Introduction:

Pinhole camera is a simple camera with small hole without any lenses with single small aperture.    Light from a scene passes through this single point and projects an inverted image on the opposite side of the box.

It is completely dark on all the other sides of the box including the side where the point is created. This part is usually painted black, but black boxes are also used for this purpose. There is also a thin screen which looks like a projector sheet, and is put in between the dark side adjacent to the pinhole.


Up to a certain point, the smaller the hole, the sharper the image, but the dimmer the projected image. Optimally, the size of the aperture should be 1/100 or less of the distance between it and the projected image.
      
 History:

pinhole lens less camera is a light-tight box with a very fine round hole in one end and film or photographic paper in the other. Light passes through the hole; an image is formed in the camera.

The image-forming ability of a tiny hole is thought to have been known thousands of years ago by nomadic tribes of North Africa, who lived in animal skin tents. A pinhole in the tent would project an image of the brilliant scene outside.

Process:

1. To do a pinhole camera, there is a process to make it work. we need such material to carryout the pinhole camera. First the material that we need is:

(a) Biscuit tin



(b) Thumb tack

(c) Shur Tape

(d) Chemical

(e) Cleaning tools for pinhole camera

2. The procedure that we use during carryout those activities:

-Identify the best place with good brightness then you may hoot.-Ready to shoot and set up your time around (2-7 seconds)

-Open the hole at camera and close.

-Then, go to the darkroom for take out the paper from camera. (do not hit the light)

-Through the paper into the chemical.

-There is 3 chemicals that have been used in this process
a) Paper developer (1;19) (2 min)
b) Stop bath (1;19) (1 min)
c) Paper fixer (5 min)

-At last, put paper in the tap water

The example of pinhole camera image

3. The problem that we have been through during this process:

a. First is the picture that we captured by this type of camera is the problem with the light.

b. Then the picture that we captured sometimes does't look like the things that we try to capture (unclear)

BLACK AND WHITE FILM

Introduction:

Black and white film is an image that have combine black and white together in a continuum providing a range of shades of gray.

Use in photography

Photography was black-and-white or shades of sepia. Color photography was originally rare and expensive and again often less than true to life. Color photography became more common in the middle of the 20th century and has become even more common since. Nowadays black-and-white has turned into a niche market for photographers who use the medium for artistic purposes. This can take the form of black-and-white film or digital conversion to gray scale, with optional digital color editing manipulation to enhance the results. For amateur use certain companies such as Kodak manufactured black-and-white disposable cameras until 2009. Also, certain films are produced today which give black-and-white images using the ubiquitous C41 color process.

Process during carryout this activity

Materials that been use in this activity

Film

 Camera

The camera will be insert with film



The film that been insert into the camera before we capture the picture

First the end of the film will be cutoff