BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Adam Foster

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Raster and Vector Images

Raster Images

Raster images are a bunch of dots called pixels, each pixel is a small coloured square. When an image is scanned, the image is converted to a collection of pixels called a raster image. Scanned graphics and web graphics (JPEG and GIF files) are the most common forms of raster images. The resolution of a raster image or scanned image is expressed in terms of the dots per inch or dpi. A printer or scanner's resolution is also measured in dots per inch.

This is an example of a raster image.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Raster and Vector Images

Vector Images

A vector image is a collection of connected lines and curves that produce objects. When creating a vector image in a vector illustration program, node or drawing points are inserted and lines and curves connect notes together. This is the same principle as "connect the dots". Each node, line and curve is defined in the drawing by the graphics software by a mathematical description. Every aspect of a vector object is defined by math included node position, node location, line length and on down the line. Text objects are created by connecting nodes, lines and curves. Every letter in a font starts out as a vector object. Vector images are object-oriented while raster images are pixel oriented. A vector object will have a "wireframe" underneath the colors in the object. In a vector object, colors are like clothes over the top of a skeleton. CorelDRAW and Illustrator create text and objects using vectors that can be easily manipulated.

This is an example of a vector image, the quality has much improved over the raster image version of this.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Anti-aliasing

Anti-Aliasing is a method of fooling the eye that a jagged edge is really smooth. Anti-Aliasing is often referred in games and on graphics cards. In games especially the chance to smooth edges of the images goes a long way to creating a realistic 3D image on the screen. Remember though that Anti-Aliasing does not actually smooth any edges of images it merely fools the eye. Like a lot of things they are only designed to be good enough. If you can't tell the difference then that's fine.

The letter on the left is a blown up letter a with no anti-aliasing. The letter on the right has had anti-aliasing applied to it. In this blown up form it looks like its simply blurred but if we reduce the size down to a more standard size you may see the difference.

The letter A on the right with the size reduced.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Resolution

Image resolution describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail. Image resolution can be measured in various ways. Basically, resolution quantifies how close lines can be to each other and still be visibly resolved. Resolution units can be tied to physical sizes (e.g. lines per mm, lines per inch), to the overall size of a picture (lines per picture height, also known simply as lines, or TV lines), or to angular subtenant. Line pairs are often used instead of lines; a line pair comprises a dark line and an adjacent light line. A Line (or TV line, TVL) is either a dark line or a light line. A resolution of 10 lines per millimetre means 5 dark lines alternating with 5 light lines, or 5 line pairs per millimetre (5 LP/mm). Photographic lens and film resolution are most often quoted in line pairs per millimetre.

Above is an illustration of how the same image might appear at different pixel resolutions, if the pixels were poorly rendered as sharp squares (normally, a smooth image reconstruction from pixels would be preferred, but for illustration of pixels, the sharp squares make the point better).

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Aspect Ratio

The aspect ratio of an image is a number to represent it’s width by its height e.g 4:3. this number would mean the width is larger than the height meaning it would be a longer image rather than a taller one.

These are both aspect ratios.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – File FormatsFile formats are things added to the end of a file name so we can see what type of file it is and what it can be used on. These are things such as .doc which tells us it’s a word document and can be used on microsoft words and other word processors. File types include:

Gif – Graphics Interchange Format: an animated image, used on something such as windows movie maker. Compresses files for smaller file sizes and faster downloads. Best for images with solid colours or areas of uniform colour such as illustrations and logos.

Jpeg - Photographic Experts Group: standard image file, can be used on almost anything which uses images. Takes advantage of the full spectrum of colours on your monitor. Also uses compression for smaller file sizes and faster downloads however unlike with a GIF file, compression discards data in the process.

Tiff – Tagged Image File Format: Used for bitmaps only, The TIFF format is supported by more or less all graphics applications. Eps - Encapsulated PostScript: A file format used for both vector graphics and bitmaps. Contains a PostScript description of the graphic data within them. EPS files are unique in that you can use them for vector graphics, bitmap images, type or even entire pages.

PSD: files that are used on photoshop and is usual file type of an unfinished photoshop image that can be opened and edited straight away.

PDF: an internet format used for electronic distribution because it maintains the look of the document and keeps the fonts, colours etc. Some of its advantages include: they are platform independent - they work with both Mac® and PC computers, the software used to read and print them is free and they contain PostScript® data and can be imported into both image editors and illustration programs just like EPS files.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Colour ModelsA colour model is an orderly system for creating a whole range of colours from a small set of primary colours. There are two types of colour models, those that are subtractive and those that are additive. Additive colour models use light to display colour while subtractive models use printing inks. Colours perceived in additive models are the result of transmitted light. Colours perceived in subtractive models are the result of reflected light. The two main types of colour models are RGB and CMYK.

RGB Colour Model CMYK Colour Model

Additive colour modelFor computer displaysUses light to display colourColours result from transmitted lightRed+Green+Blue=White

Subtractive colour modelFor printed materialUses ink to display colourColours result from reflected lightCyan+Magenta+Yellow=Black

RGB Colour Models are used for things you see on a screen where CMYK is used for ink for print.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Adobe Photoshop

Adobe Photoshop is an adobe software used for image manipulation and editing and is one of the best software's for that job. It has endless features on it for editing images such as filters to change the way images look, clone tool to remove things from images and make it look like it never was removed and other features. It is often used to make celebrities look more attractive on magazines and adverts to make it more appealing to the audience.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Adobe Illustrator

Adobe Illustrator is an Adobe software used mainly for the creation of images but can also has a few features for editing images. It allows you to create images neatly and in detail with its many features. Features include being able to create many shapes to your preference, advanced pen tools, advanced text tools and more.

BTec Level 3Extended Diploma in Creative Media Production

HA1 - Technical File – Adobe InDesign

Adobe InDesign is an adobe software used to create newspapers, flyers, posters, magazines and more. It has the features to create documents in the layout of newspapers, magazines etc and has many different text features as well which can be used to make the document look accurately like what it’s meant to look like.

Anti-Aliasing: http://www.pantherproducts.co.uk/Articles/Graphics/anti_aliasing.shtml

Raster and Vector Images: http://www.signindustry.com/computers/articles/2004-11-30-DASvector_v_raster.php3

Resolution: http://en.wikipedia.org/wiki/Image_resolution

Aspect Ratio: http://en.wikipedia.org/wiki/Aspect_ratio_(image)

File Formats: http://www.prepressure.com/library/file-formats/eps http://en.wikipedia.org/wiki/Tagged_Image_File_Formathttp://www.basictemplates.com/psd.shtml http://www.direct.gov.uk/en/Hl1/Help/DG_10014666

Colour Models: http://en.wikipedia.org/wiki/Color_model

Adobe Photoshop and Adobe Illustrator: own knowledge

Adobe InDesign: http://en.wikipedia.org/wiki/Adobe_InDesign

Sources