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Point and Shoot!

Just the basic stuff to get you up and shooting.


Taking Photos in Automatic Mode

All digital cameras have an automatic mode that sets focus and exposure for you. All you have to do is frame the image and press the shutter button. Great in vast majority of situations because it lets you focus on the image and not on the camera.

Good things to know before you first start taking photos.

The first time you use the camera you should enter the date and time. This will help you organize, locate, and identify your images later. Always check camera settings on the control panel. Most shutter buttons have two stages. When you press halfway down, the camera sets focus and exposure. When you press it all the way down, you take the picture. If the viewfinder appears blurry adjust the diopter. As you take your photos they first stored in the cameras internal memory called buffer. When the buffer is full youll have to wait until the images has been transferred to the memory card before taking any more pictures.

Don't open the battery or memory card access covers while an image is being saved. Doing so can not only damage the image being saved, it can also damage the card. Take as many shots of a given scene as you can think of; changing positions, distances, and angles. You may be surprised later at what works and what doesn't. When done shooting turn off the camera.

When Things Go Wrong.

If you can't turn on the camera, the batteries are dead or have been removed or a memory card hasn't been inserted If your batteries drain quickly, stop using the monitor to take and review pictures. If it's cold, keep the batteries or camera under your coat. If you can't take a picture, it may be because the memory card is full. To free up room for new pictures, move the images to a computer and erase the memory card, delete some you don't need, or switch to a smaller image size. Some cameras have a delay between your pressing the shutter button and the shutter opening. This can cause you to miss fleeting expressions.

If the focus lamp blinks when you press the shutter button halfway down, the camera may be having trouble focusing. If flash photos are too dark, you are probably too far from the subject. Most built-in flash units are good only up to about ten feet. They don't have the power to illuminate subjects much father than that. Never take pictures of the sun or other bright light sources. Doing so can injure your eye or the camera's image sensor. If your pictures are not at all the way you expect, it may be because the camera remembered a change you made in the settings and continues to use that changed setting. Some cameras remember changes even when you turn a camera off and back on. See if your camera has a procedure that resets all settings to their factory defaults.

Types of Digital Cameras

Camera Phones

Point and Shoot

High End Fixed Lens

Digital Single Lens Reflex

Understanding Image Size and Quality

Digital photographs are actually mosaics of millions of tiny squares called picture elements or just pixels. Like the impressionists who painted wonderful scenes with small dabs of paint, your computer and printer can use these tiny pixels to display or print photographs. To do so, the computer divides the screen or printed page into a grid of pixels. It then uses the values stored in the digital photograph to specify the brightness and color of each pixel in this grida form of painting by number.



Number of Pixels


The term "resolution" has two meanings in photography. Originally it referred to the ability of a camera system to resolve pairs of fine lines such as those found on a test chart. In this usage it's an indicator of sharpness, not image size. With the introduction of digital cameras the term began being used to indicate the number of pixels a camera could capture.

The pixel size of a digital photograph is specified in one of two waysby its dimensions in pixels or by the total number of pixels it contains. For example, the same image can be said to have 4368 2912 pixels (where "" is pronounced "by" as in "4368 by 2912"), or to contain 12.7 million pixels or megapixels (4368 multiplied by 2912).


Exploring the size of printed images

Width of image (in pixels) Height of image (in pixels) Pixels printed per inch (ppi) Width of print (in inches) Height of print (in inches) 1600 pixels 2000 pixels 200 pixels 8.00 inches 10.00 inches

How An Image is Captured


The plate is called a waterhouse stop, was inserted into a slot in the lens. The size of the stop's hole acted just like the iris apertures used today. A lens cap was removed and then replaced to begin and end the exposurea primitive version of a shutter. This vintage camera is surrounded by waterhouse stops (apertures) and a lens cap (the shutter) leans against it.

The big difference between traditional film cameras and digital cameras is how they capture the image. Instead of film, digital cameras use a solid-state device called an image sensor. In some digital cameras the image sensor is a chargecoupled device (CCD), while in others it's a CMOS sensor. Both types can give very good results. On the surface of these fingernail-sized silicon chips are millions of photosensitive diodes, each of which captures a single pixel in the photograph to be.


Its Black and White After All

It may be surprising, but pixels on an image sensor only capture brightness, not color. They record the gray scalea series of tones ranging from pure white to pure black. How the camera creates a color image from the brightness recorded by each pixel is an interesting story with its roots in the distant past.



RGB uses just three basic colors to create full color images.


Image Formats
One of the most important choices you'll make when shooting photos is what format to use JPEG or RAW.
JPEG is the default format used by almost every digital camera ever made. Named after its developer, the Joint Photographic Experts Group this format lets you specify both image size and compression. The smallest size is best for the Web and e-mail (although it will usually have to be reduced) and the largest for prints.

The JPEG format compresses images to make their files smaller. This is a useful feature because there is a trade-off between compression and image quality. Less compression gives you better images so you can make larger prints, but you can't store as many images.




In most cases its hard to tell the difference between images shot in RAW and JPEG formats. The differences become most apparent when an image needs serious adjustment to its tonal range as underexposed images do.

RAW images have 16 bits per pixel and they give you over 65 thousand levels of gray to adjust. JPEGs use only 8 bits per pixel hence have only 256 levels of gray per pixel.

Exposure Controls




Understanding Exposure
The amount of light that strikes the sensor determines how light or dark the captured image is. As the sensor gathers more light, the image becomes lighter. There is only one point, or perhaps a narrow range, where it is perfectly exposed.

Exposure Modes
Modern digital cameras have sophisticated ways of controlling the aperture and shutter speed. In fully automatic mode the camera sets them both to produce the best possible exposure. However, there are other exposure modes that are widely used in digital photography. All modes give equally good results in the vast majority of photographic situations. However, when you photograph in specic kinds of situations, each of these exposure modes may have certain advantages.

Basic Zone

Creative Zone

Photographic Concepts
You dont really have to but if you learn a few photography concepts those numbers on the camera will start to make sense.

The Shutter Controls Light and Motion

The shutter keeps light out of the camera except during an exposure, when it opens to let light strike the image sensor. In respect to just exposure, faster shutter speeds let less strike the image sensor so the image is darker. Slower speeds let in more so it's lighter.

As the shutter speed gets slower, the image gets lighter. The reason you don't usually see this effect in your images is because when you or the camera change the shutter speed,the camera changes the aperture to keep the exposure constant.

In addition to controlling exposure, the shutter speed is the most important control you have over how motion is captured in a photograph. The longer the shutter is open, the more a moving subject will be blurred in the picture. Also, the longer it's open the more likely you are to cause blur by moving the camera slightly. Although you normally want to avoid blur in your images there are times when you may want to use it creatively.

The Aperture Controls Light and Depth of Field

The aperture adjusts the size of the opening through which light passes to the image sensor. The aperture can be opened up to let in more light or closed (stopped down) to let in less. In respect to just exposure, smaller apertures let less light strike the image sensor so the image is darker. Larger apertures let in more so it's lighter.

In better cameras, the aperture is a series of overlapping leaves located between the glass elements in the lens.

As with the shutter speed, the aperture also affects the sharpness of your picture, but in a different way. Changing the aperture changes the depth of field, the depth in a scene from foreground to background that will be sharp in a photograph. Smaller apertures increase depth of field while larger ones decrease it. For some picturesfor example, a landscapeyou may want a smaller aperture for maximum depth of field so that everything from near foreground to distant background is sharp. In a portrait you will want a larger aperture to decrease the depth of field so that your subject is sharp but the background is soft and out of focus.

A small aperture increases depth of field so foreground and background are sharp (top) and a large aperture decreases depth of field so the background is soft (bottom).

How wide you can open the aperture depends on the len's maximum aperture its widest opening. The term "fast lens" usually applies to lenses that can be opened to a wide maximum aperture for the focal length. For example, a lens with a maximum aperture of f/1.8 opens wider, and is faster, than a lens with a maximum aperture of f/2.6. Faster lenses are better when photographing in dim light or photographing fast moving subjects.

Using Shutter Speed and Aperture Together

When taking photos, one of the first decisions you make with many cameras is which exposure mode to use. Your choice determines if you control the aperture or shutter speed. If your camera lets you select them, you can pair a fast shutter speed (to let in light for a short time) with a large aperture (to let in bright light) or a slow shutter speed (long time) with a small aperture (dim light). Speaking of exposure only, it doesn't make any difference which combination you use. But in other ways, it does make a difference, and it is just this difference that gives you some creative opportunities. Whether you know it or not, you're always balancing camera or subject movement against depth of field because a change in one causes a change in the other.

Exposure - Faucets and Buckets Analogy

One way to think of apertures and shutter speeds is to use the analogy of a faucet for the aperture and a timer for the shutter speed.

When you open a faucet all the way, water gushes out so you fill a bucket in a very short time. This is the same as pairing a large aperture and fast shutter speed to let in bright light for a short time. When you open a faucet just a little, water trickles out and so it takes a much longer time to fill a bucket. This is the same as pairing a small aperture and slow shutter speed to let in dim light for a longer time. No matter which combination you choose, the bucket is filled the same amount. Likewise, an image in a camera can be exposed the same amount by various aperture and shutter speed combinations while also controlling motion and depth of field.

Exposure - Seesaw Analogy

Another way to think of exposure is as a seesaw. As one child rises a given distance, the other falls by the same amount but their average distance from the ground is always the same. In photography, when you or the camera changes the aperture or shutter speed to let in more or less light, you or the camera must also change the other setting in the opposite direction to keep the exposure constant.

Here the aperture is f/4 and the shutter speed is 1/125.

If you reduce the aperture one stop to f/5.6 the shutter speed has to decrease one stop to 1/60 to keep the exposure the same.

Depth of field increases slightly and the possibility of subject or camera blur increases.

A great photographs begins when you recognize a great scene or subject. But recognizing a great opportunity isnt enough to capture it; you also have to be prepared. A large part of being prepared involves understanding you camera well enough to capture what you see the you want to interpret it. This concepts of photography are the underlying principles that apply regardless of the camera you are using.

When people tells me that my photograph is worth a thousand words and asks what equipment I use...?

I tell them my eyes...! :)


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