digital imaging week 3

Digital Imaging

• Week 3: What IS digital Imaging?

Digital Film• The heart of a digital camera is the

sensor.

Digital Film• The heart of a digital camera is the sensor. • This takes the form of a CCD - a grid of

Charged Coupled Devices.

CCD Grid

Digital Film• The heart of a digital camera is the sensor. • This takes the form of a CCD - a grid of

Charged Coupled Devices.

CCD Grid

•These measure the amount of light.

It’s Black & White

It’s Black & White

Red Separation Green Separation Blue Separation

CMYK

Cyan

Magenta

Yellow

Black

Understanding Digital Imaging

• Pixels

• Pixels

Each pixels holds 3 bytes of information: red, green & blue.

The Digital Process

The Digital Process Shooting• Image is composed and shutter released

The Digital Process Shooting• Image is composed and shutter released• Light hits the sensors and each receives a slightly different amount of light.

The Digital Process Shooting• Image is composed and shutter released• Light hits the sensors and each receives a slightly different amount of light. • In response to light, each CCD produces an electronic charge - the more light,

the bigger the charge. The sensors are filtered with RGB.

The Digital Process Shooting• Image is composed and shutter released• Light hits the sensors and each receives a slightly different amount of light. • In response to light, each CCD produces and electronic charge - the more light,

the bigger the charge. The sensors are filtered with RGB. • The electronic pulses are collated, converted to digital information and stored

according to their position on the CCD. This uses a special chip called an ADC chip.

The Digital Process Shooting• Image is composed and shutter released• Light hits the sensors and each receives a slightly different amount of light. • In response to light, each CCD produces and electronic charge - the more light,

the bigger the charge. The sensors are filtered with RGB. • The electronic pulse are collated, converted to digital information and stored

according to their position on the CCD. This uses a special chip called an ADC chip.

• This information is stored on the cameras memory card and the camera is ready to take another shot.

The Digital Process Processing & Manipulation

• The digital files are now transferred to your computer. • This can now be enhanced or manipulated using programs like Adobe

Photoshop. • The enhanced picture is then saved to the computers hard drive.

The Digital Process Outputting

Web

Printer

CD/DVDs

What does Mega Pixel really mean?

1536 x 2048 = 3 million

What does Mega Pixel really mean?

2800

pix

els

1536

pix

els

2048 pixels 3008 pixels 4290 pixels

2800 x 4290 = 12 million

2000 x 3008 = 6 million

2000

pix

els

Dots Per InchUsed when printing - pixels are turned into dots per inch and counted by the spread Over the paper.

Dots Per InchUsed when printing - pixels are turned into dots per inch and counted by the spread Over the paper.

DPI Printer dots

Digital & Optical Zoom

Interpolation

• Any means of calculating a new point between two existing data points.

Interpolation

• Any means of calculating a new point between two existing data points is therefore interpolation

Image Formats

• Joint Photographic Experts Group

JPEGS


• Can change image size & compression

JPEGS


• Can change image size & compression• Good for web & printing

JPEGS



• Fit more on a device

JPEGS



• Fit more on a device

• Universal file format

JPEGS

Downsides:

• Loss of quality

JPEGS

Downsides:

• Loss of quality

• Less powerful processing

JPEGS

Downsides:

• Loss of quality

• Less powerful processing

• Less control over image

JPEGS

• Processed on computer not camera

RAW


• Contain every bit of data recorded

RAW


• Contain every bit of data recorded• Large format printing

RAW


• Contain every bit of data recorded• Large format printing

• Colours more accurate

RAW

Downsides:

• Much bigger file sizes

RAW

Downsides:


• Not always compatible

RAW

Downsides:


• Not always compatible

• No preview

RAW

Memory Cards?

•Secure Digital (SD)

•Mini SD

•Micro SD

•Compact Flash I & II (CFI & CFII)

•xD-Picture Card

•Smart Media

•Memory Stick/ Memory Stick Duo

•Internal memory

Downloading

• USB 1.1 & 2.0

• Card reader

• Bluetooth

• Firewire

• Scanning!

Memory Cards

• DON’T TAKE OUT UNTIL CAMERA IS TURNED OFF!!

Memory Cards

• DON’T TAKE OUT UNTIL CAMERA IS TURNED OFF!!

• DON’T PULL OUT USB/CARDS FROM COMPUTER UNTIL EJECTED!!

Saving• Organisation is key!


Folders


Applications

Digital Manipulation

• We’ve composed our picture, set up our camera, transferred the image

on to the computer, saved and organised it.




• Most home computers are ideal for manipulating images.





• Photo stores normally won’t tweak images for you






• Manipulation can be very subtle, not necessarily any crazy effects! A

bit brighter, a bit more contrast etc.






• Manipulation can be very subtle, not necessarily any crazy effects! A bit

brighter, a bit more contrast etc.

• Photoshop elements - only about £60, will provide you with most of

your photographic needs. Photoshop (full version) has more features

but costs about £1000!!!!!


• We’ve composed our picture and set up our camera. Got the image on the

computer, saved and organised it.



• Manipulation can be very subtle, not necessarily any crazy effects! A bit brighter,

a bit more contrast etc.

• Photoshop elements - only about £60, will provide you with most of your

photographic needs. Photoshop (full version) has more features but costs about

£1000!!!!!

• It’s not difficult!!

Some basic digital processing options

• Basic Image

• Dodging & Burning

• Crop & resizing

• Changing Saturation

• White balance

• Adjusting brightness & Contrast

• Retouching or deleting details

• Converting to grayscale

• Adding filters or effects

Scanning

Scanning

Why still scan when we have digital cameras?

digital imaging week 3

Art & Photos