digital photography: basics. materials camera and memory card(s) usb cable for camera or card reader...

Digital Photography:

BASICS

Materials

• Camera and memory card(s)

• USB cable for camera or card reader

• Blank CD’s, DVD’s or external hard drive / jump drive

PHOTOGRAPHY

• Foton=light• Graphos=to write or draw• Photography=DRAWING WITH LIGHT• Light is the key tool of photography

Light Meter• The light meter is a light sensitive cell that

tells the camera which settings to use in order to obtain a perfectly balanced exposure

• In photography, exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph

• The light meter reads an average of light and dark tones (18% gray)

Light Meter Types andShooting Modes

• Automatic• Semi-automatic with aperture

priority• Semi-automatic with shutter

priority• Manual

Camera Controls

• All analog and digital point and shoot and SLR cameras cameras have 2 main parts that control the exposure:

– Shutter– Aperture

Shutter

• The camera’s shutter allows light to pass through the lens and onto the film or digital sensor

• The shutter is a curtain-like apparatus made of metal, plastic or cloth, situated behind the lens but before the film or sensor in the body of the camera

Shutter

• The shutter’s movement is expressed in seconds or fractions of seconds

• Shutter speeds range anywhere from 60 seconds to 1/8000 second

• This speed represents the amount of time the shutter is open, allowing light to pass through

Shutter

• The camera’s shutter also controls how movement is captured

• Examples:– 30 sec shutter speed = slow shutter

speed• Movement will come out blurry

– 1/8000 sec shutter speed = fast shutter speed• Movement tends to come out frozen or sharp

Aperture

• The aperture (opening) of the camera’s diaphragm allows light to pass through the lens and onto the film or digital sensor

• The diaphragm is a mechanism similar to the iris of the eye and is located in the lens in front of the shutter

Aperture

• The aperture size is expressed in f stops

• F stops range anywhere from f/1.4 to f/32

• F stops represent the length of one side of the diaphragm (from the edge to the aperture) in millimeters

Aperture

• The camera’s aperture also controls depth of field

• Depth of field: the distance in front of and behind the point of focus in which the scene remains in focus

• Examples:– F/1.4 = wide aperture

• Only 1 plain is in focus

– F/32 = small aperture• Almost all plains are in focus

How It All Works Together

• Once we have decided on what our subject matter will be, the camera sets the shutter speed and aperture in the correct combination to give us a perfect light exposure (not too light, not too dark)

• At the same moment we press the shutter release button, the shutter opens for the designated period of time and image is registered on the film or sensor.

Histograms

• A histogram is a graph of shadows, highlights and mid tones

• The histogram tells us how these tones are dispersed throughout the image

• A visual representation of our exposure

Under Exposure

• Underexposure is when the image is given less than the normal exposure

• Overexposure is when the image is given more than the normal exposure

Over Exposure

ISO/ASA• The ISO (sometimes called ASA)

represents the sensitivity of the film or sensor to light

• ISO presets in modern cameras can range from 100 to 3200

• ISO, along with aperture and shutter speed, is also very important in obtaining the proper exposure

ISO

• Lower ISO numbers = less sensitivity to light, slower shutter speeds, less pixelation or “noise”, better image quality– Better for high light situations

• Higher ISO numbers = more sensitivity to light, faster shutter speeds, more pixelation or “noise”, lower image quality– Better for low light situations

The 5 Important Photographic Elements:

• Composition• Color/tone• Contrast• Content• Concept

• Composition: the way the photographer places or composes the subjects/objects in an image

• Composition can be controlled by the position of the photographer: different angles, heights or distances

• Color/Tone is a design element that can elicit immediate responses and create moods

• We tend to respond differently to certain colors and color combinations

• Contrast: the range of tones across an image from the bright highlights to the dark shadows

• Images can have low, mid-range or high contrast

• Content: the subjects or objects that appear in the image

• Certain subjects and objects can have certain implications and can transmit different messages to the viewer

• Concept: what your art means to you. The concept can also be the reason behind the work.

• The concept must be understood by both the artist and the viewer

• Concepts can emerge before, during or after creating the work

Inside Your Digital Camera

• Instead of film, we now have a digital sensor, a processor, a memory card and an LCD screen

• Our images are now in different digital formats and different qualities according to the camera’s sensor capacity (megapixels)

Megapixels• A pixel is the smallest unit of a

digital image. Pixels are square dots that make up an image. Each pixel carries a specific tone and color.

• Pixel stands for PICture ELement• 1 megapixel = 1 million pixels• More pixels = greater detail• Also important are the camera’s

processor and the quality of the lens

• Cameras with more megapixels usually have higher quality processors, produce better color and create less “noise”

• Noise: any undesirable flecks of random color in a portion of an image that should consist of smooth color. It is somewhat similar to the "snowy" appearance of a bad TV signal. Digital images shot in low light or with a high ISO setting often exhibit this undesirable noise.

File Formats

• JPEG (Joint Photographic Experts Group): this is the most common file format, which uses algorithms to compress digital information and reduce the size of files

• Compression requires that some image information be thrown out

• If you have to shoot in jpg, shoot in the highest quality jpg (large)

JPEG Warning

• Every time you open, change and re-save a JPG, you recompress data.

• By recompressing data, you lose more image information, resulting in a lower quality image

• To avoid this, save jpgs in Photoshop as TIF’s or PSD’s

File Formats

• TIFF (Tagged Image File Format): a universal image format that is compatible with most image editing and viewing programs. It can be compressed in a lossless way.

• TIFF is widely used as a final format in the printing and publishing industry.

File Formats

• PSD (Photoshop Document): you cannot actually photograph in this file format, but you can save your image manipulations in Photoshop in this format.

• PSD format allows you to save your image with layers so that you can go back to it later

• PSD´s are typically larger files

File Formats

• RAW: this is the original file format of your camera (not all cameras have RAW format)

• Examples of raw formats are NEF (Nikon) and CR2 (Canon)

• RAW format contains all of the original information and this is the ideal format to shoot and edit with

Focal Length

• This is the actual measurement in millimeters between the lens optics and the focal plane

• The lens optics are the main pieces of glass in the lens

• The focal plane is the location of the digital sensor

• For example, the focal distance of my lens is 75mm

Optical Zoom vs. Digital Zoom

• The optical zoom of a camera is the variance of focal distance in the lens

• This allows you to take full advantage of your camera’s megapixels

• Digital zoom is not produced in the lens, rather in the processor. The camera crops a portion of the image and then enlarges it.

• Optical zoom is always better quality

White Balance• White balance (WB) is the process of

removing unrealistic color casts so that objects which appear white in person are rendered white in your photo.

• Proper camera white balance has to take into account the "color temperature" of a light source, which refers to the relative warmth or coolness of white light.

• Our eyes are very good at judging what is white under different light sources, however digital cameras often have great difficulty with auto white balance (AWB).

White Balance• An incorrect WB can create unsightly

blue, orange, or even green color casts, which are unrealistic and particularly damaging to portraits.

• Many times it is best to use Auto White Balance, but experimenting with different settings is recommended

• White balance can be easily fixed in Camera Raw in Adobe Photoshop if you are shooting in RAW format

How the Digital Sensor Works

• The sensor is composed of light-sensitive cells (photoreceptors) and circuitry on a microchip that react to light intensity

• An average 11 megapixel sensor contains about 700 feet of circuitry

• The photo receptors on the sensor contain photodiodes which convert the photons of light striking it to a charge

• The more light, the higher the charge

• The charge is then processed and each signal from each photodiode becomes the light and color value for one pixel

Workflow

• After shooting:– 1) transfer images right away to your

computer– 2) organize your images in folders

according to date and subject– 3) make a back up

• CD or DVD• External hard drive

– 4) browse images and add metadata in Adobe Bridge CS3 or Adobe Lightroom

Digital Photo Terms

http://www.dpreview.com/learn/?/Glossary/

http://www.nikonians.org/html/resources/photography-glossary.html

Online Tutorials

http://www.cambridgeincolour.com/tutorials.htm

http://www.russellbrown.com/tips_tech.html

http://www.lynda.com/

Text Recommendations

• The Digital SLR Handbook by Michael Freeman

• Adobe Photoshop CS3 for Photographers: A Professional Image Editor's Guide to the Creative use of Photoshop for the Macintosh and PC by Martin Evening

• George DeWolfe's Digital Photography Fine Print Workshop by George DeWolfe

Digitally Manipulated Images

David Field

Loretta Lux

Dominic Rouse

Julie Blackmon

Dan Saelinger

Michelle Repici

Anthony W. Grigas

In Class Exercise

• Shoot in jpg file format, highest quality• Set ISO• Set WB• Shoot portrait or self-portrait with natural

light• Shoot a portrait/self-portrait with fill flash• Shoot a portrait/self-portrait with a slow

exposure so that the image captures motion