Digital Cameras

Image CaptureImages are captured by the image sensor, then stored in the camera in a memory device. Sensors convert light into an electric charge and process it into electronic signals. Image sensors are, with the exception of the lens, the most important part of the camera.The sensor is basically a digital camera’s film! Images must be transferred (downloaded) to a PC and stored on a storage device-usually a hard drive. Images are compressed in the camera so there is more room on the storage device.

Understanding Image Size: *The quality of a digital image depends on the number of pixels used to create the image.

*More pixels= more detail, sharper edges and greater resolution.

* Enlarge any digital image enough, the pixels will show= “pixelization”.

*A digital image displayed at the correct size for the number of pixels it contains, looks like a normal photograph.

Image Compression and Quality

*The process of reducing the file size of a picture when storing it is called compression. In most digital cameras, pictures are compressed and recorded as JPEG files.

*The more the picture is compressed 1. more pictures can be stored on the memory card 2. the quality of the image is degraded3. the reproducibility of the image is reduced *The less a picture is compressed1. fewer images can be stored2. maintains the presentation of the image’s fine areas3. increases the image quality

* Image quality must be set before the pictures are shot so the final result is what you expected.

* The Large or RAW quality are the best options for photographers.

RAW VS. JPEG

RAW files:☼ give the best image quality and the most flexibility.☼ do not contain pixels! A RAW file is raw sensor data.☼ capture two more stops of dynamic range that JPEGs. This creates

better shadow detail.☼ require post processing in the computer.☼ take up a large amount of space on the memory card and the computer.

JPEG files: ☼ take up less room on the memory card and the computer.☼ are compressed in the camera and carry less information (detail)☼ have less flexibility and a lower image quality.

Image Recording Quality:

Option Image Type Pixels/Print Size

LARGE/FINEFine image quality, suitable for enlargements or high quality prints. JPEG

3405x2336 pixels8x10 or larger

2544x1696 pixelsSmaller than 8x10

1728x1152 pixels

3504x2336 pixels8x10 or larger

LARGE/NORMALNormal image quality, suited to most applications. JPEG

MEDIUM/FINE

MEDIUM/NORMAL

SMALL/FINE

SMALL/NORMAL

RAW

Basic image quality, suitable for pictures that will be distributed by e-mail or used in web pages. JPEG

JPEG

JPEG

JPEG

RAW images must undergo post processing in the computer.

Getting to know your Camera

Camera ModesCreative Zone

*P - program mode *Tv - shutter speed priority mode *Av - Aperture mode *M - Manual mode *A-Dep - Automatic Depth of Field-good for

group photos and landscapes

Basic Modes: *Portrait Assist-shallow depth of field *Sport Assist-will freeze action *Landscape Assist *Close Up *Night Assist-good for shooting people at night; may need a tripod *Flash Off- disables the flash

Camera Modes continued…AF Mode= auto focus mode. Select the type of auto focus the subject requires.

One Shot AF is good for still subjectsAl Servo AF is good for moving subjectsAl Focus AF switches back and forth automaticallyFocus Lock: when you want to focus on a specific item in the

picture and recompose without losing your original focus. Only works in One Shot AF mode.Metering: In the Basic zones metering is set automatically. There are four metering modes:

Evaluative-standard mode suitable for most subjects.Partial-effective for backlighting; meters about 9% of viewfinder

image.Spot-This is for metering a specific spot. About 3.5% of the very

center of the viewfinder is weighted for focusing.Center weighted averaging-averages the entire scene.

Auto Mode: (aka- green moron mode) Step out of the box and learn the other modes of the camera!Drive Mode: Single and continuous modes are available. Continuous mode allows you to shoot continuous bursts of images. This allows greater opportunity to catch action.

Metering Examples

Evaluative Metering Center-Weighted Metering

Partial/SpotMeterig

Film Speed:Film Speeds= ISO (International Organization for Standardization)The higher the ISO number the more sensitive to light the camera will be, but more noise (grain) will be in the captured image.Basic Zone- ISO is set automatically between 100 and 400.To set the ISO choose one of the Creative Modes, then press the <Drive-ISO button> and turn the dial.

White BalanceThe sensor in the camera renders light the exact color that it is; giving the image an odd color cast in some light. The digital camera has settings for different light sources so the image comes out the correct color; this is the white balance control.Shoot in RAW and this can be adjusted after capture.

– AWB (Auto White Balance)-The camera will try to balance the scene for accurate color. This works best in an artificial lighting set up.

The White Balance Settings– Daylight-(blue light) is good for Daylight and when shooting sunsets,

sunrises and night scenes.– Cloudy-(blue gray) will add orange/yellow to the image to fix the blue

cast on cloudy days. On a bright sunny day, you can use the cloudy setting to get a warmer feeling in your photos.

– Open Shade-(very blue) will add even more orange/yellow than cloudy.– Fluorescent-(green light) this will add a pinkish color to balance the

overall green cast of the light.– Tungsten-(orange light) this will add blue to over come the heavy orange

cast.– Flash- is designed to give you good color when using the on camera flash; it

adds a yellow cast. The cloudy setting can be used instead to give a warmer feeling.

– Custom-this is the most accurate setting and is best used in any light source other than day light.

– WB Bracketing - Some cameras are able to bracket the white balance settings (does not work with RAW setting). This gives you three different color images of the same shot.

Getting Started

Now you are ready to take some pictures!Make sure you have a CF card loaded and a charged battery before you go out.If no one needs the images on the card reformat it before you begin.Set the image recording quality (RAW or Large).When the shots are taken use the card reader to download the images with Adobe Bridge.

Web Sites for Reference

http://its.leesummit.k12.mo.us/digitalmedia.htmhttp://www.edzone.net/%7Emwestern/tutorials.htmlhttp://www.internet4classrooms.com/http://www.microsoft.com/windowsxp/using/moviemaker/create/default.mspxhttp://www.picnik.com/app#/in/uploadhttp://www.wrigleyvideo.com/videotutorial/index.htmhttp://www.jumpcut.com/http://www.shortcourses.com/choosing/contents.htm