Digital Imaging:

Digital Imaging is the creation of visual objects through the use of electronic systems such as a camera or computer that is stored as code.

Digital Imaging History:

Image manufacturing begain when people started first creating art. A very early example of this would be the cave paintings of lascaux. You can see how the people of that time tried to capture the essence of the animals they saw.

Painting was the preferred method for image production for hundreds of years, reaching perhaps its peak during the renaissance in the 1300’s. Master painters, such as the ninja turtles (leonardo, donatello, michealangelo, raphael), were commisioned to render life-like portraits as well fantastic scenes.

Some artists used a camera obscura (a box with a pinhole that allows light to project through it and against the opposing wall, resulting in an image that may be used as a reference) to create accurate landscape illustrations. The next major issue was capturing the image permanently. Slowly different processes were developed utlizing various chemicals (silver based) in order to capture the image directly on various materials. Finally by the early 1900’s film based photography became prominent and popularize by George Eastman who founded Kodak.

Analog photography was the preferred method for image capture even when digital cameras became commercially available in the 1980’s. In 1990 Adobe Photoshop was introduced. Initially it mimiced the same dark room processes of traditional photography but eventually more advanced tools were implemented allowing artists to manifest images not tied to the real world.

Digital photography has become ubiquitous with the advent of modern cell phones. Along with cell phones, digital imaging apps have become abundant and accessible. More and more advanced tools have developed. First was basic selection and masking, then content-aware, and now generative imagery (AI). 

Raster/Pixel/Bitmap:

Raster graphic images are a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium.
A pixel is one picture element. (like putting picture and element together).
A bitmap is the grid that contains all the pixel information (it is inherently rectangular).
Raster images are great for photos or anything with detail. They tend to be larger files so often a codec is used to lower the file size.

DPI:

Dots per inch.

Used for print.

PPI:

Pixels per inch.

Used for screens.

The greater number of dots/pixels, the higher the resolution the image but the larger the file size.

300 dpi is the excepted standard for printed content. 72 ppi is the standard for screens (tv, monitor, etc.) any less and things get pixelated.

Common Raster formats:

JPEG (Joint Photographic Experts Group, they developed it):

lossy, but are small and compatible with most computers.

Best for images with smooth transitions (paintings, photographs, not line art).

Very common on the internet.

GIF (graphics interchange format):

Very small lossy format, also supports simple animations (like those smiley face animations).

PNG (portable network graphics):

Made to replace GIF, very small, good for transferring images over the internet.

TIFF (Tagged Image File):

Not lossy and can contain an alpha channel.

Adobe owns the rights and is often used for publishing and page layouts.

PSD (Photoshop document)

Adobe Photoshop’s native format. This can only be opened with Photoshop so it is not ubiquitous. It does however, store all of things you have done in the program. This should be your default format you save to.

Camera Raw (CR2, NEF, SRF, and many more)

When you take photos with a professional camera it is possible to save them to the camera’s native format. These are very large and difficult to work with but are high fidelity. It is generally not suggested to use this format for this course initially.

Color Modes:

Photoshop has a variety of color modes available. This will affect how the image’s color is encoded (or not).

Color Bit Depth:

This determines how many colors are available. It is determined by basic math, basically just square the number.

This is great article on it that will explain it better: Cambridge in Color.

Color Space:

Color Space represents the range of color possible. This means how much color can be represented. For instance, the amount of green you can see in person is less than what sRGB can represent.

Here is a nice article explainiing it better: The Essential Guide to Color Spaces.

Photoshop

Digital Imaging I will focus entirely on using Adobe Photoshop to manipulate and create imagery. This program has become the standard in many industries including photography and graphic design.

The Interface

click on accordion below to learn about the different panels in Adobe Photoshop.

Did you remember to?

• Familiarize yourself with Blackboard
• Read through this webpage
• Submit Week 01Basic Image Editing Assignment on Blackboard
  • original image, enhanced image, creative image, and project cover sheet