1. Vector and raster Graphics
Raster Graphics
Raster images or rasterised images are made up of many different coloured pixels, raster graphics
allow for a greater amount of colours compared to the vector images that are very limited on the
colour you’re allowed to use. Raster images have downsides one of these being that it cannot be
stretched or enlarged much once its created because they tend to stretch the individual pixels in the
image, therefore making its appear blurry and overall give it a very low quality that is not fit for
publication.
There are many different raster drawing packages out there, one of the most known being
Photoshop which allows the user to create or modify Photos, these can be images that look as
stunning as photos. Photoshop allows for many more colours than packages such as illustrator which
limits colour. Photoshop allows for exactly 16 million colours if you are creating a 24 bit photo file, 8
bit allows for 256 different colours and 1 bit is black and white colour selection. Photo files which
are normally created using flash (24 bit) has the greatest amount of colour which is why it’s used for
modifying photographs and for creating concept art, and photo-realistic images in general.
The pixilation happens when trying to stretch a raster image, this is because you are stretching the
individual pixel, and this makes the overall quality much worse and creates a blurry and distorted
appearance. Another raster drawing package is paint which is free compared to the expensive
Photoshop package from adobe. Paint does not allow for a much freedom as Photoshop does with
how you create an image and does not allow for as many colours it uses an 8 bit instead of the
Photoshop’s 24 bit. And does not allow for Photo perfect modification like Photoshop does. Though
it does come free when you purchase a PC. Photoshop has a greater amount of tool as the user’s
disposal, which of course gives it more freedom to the user. Paint gives the necessary amount of tool
to create and modify some images, but does not give the overall professional look when finished
this is why Photoshop is used in the big media industry to air brush models and such to create
professional looking images worthy for publication in magazines.
Raster images use different file formats to other types of images such as vector.
The Raster file types are. Gif, Tif, BMP, JPEG and PSD these are the raster file
types, Photoshop file type is a PSD and can hold a greater amount of colour 24
bit which is 16 million different shades of colour.
2. Vector and raster Graphics
Vector drawing packages such as adobe illustrator are mostly used to create graphics which can be
used for logos or cartoons another adobe program for vector animation is Adobe flash this allows
the user to create vector images/characters but then allows animation and also creation of websites.
Vector lines are made up for a formula instead of pixels like the raster images this allows vector
images to be stretched as far as you want without pixilation this is ideal for posters and billboard
adverts and most importantly for logo creation because after they are made they can be sized to fit
anything that you need.
Flash is greater for making vector images to animate rather than making logos, this is because flash
has more animation type tools at the users disposal whereas illustrator has a lot more logo and
shape creating tools with additional graphic layers so that you can overlap colours, shapes and
images to create any graphic that you could imagine. They both require an equal amount of skill to
master, vector images cannot use as many colours as bitmap and mostly only use solid colours,
which is great if you’re creating cartoons or solid colour graphics.
Metafiles use both vector and raster file types into a metafile which uses the best of both. A
common use for these file types is for operating systems and computer graphics, so you can
minimize space use by combining the types of graphic files (raster and vector).
File extensions and their uses:
All file types fit different uses and purposes some are for print while other are used on the web, each
file type has a role.
AI files: Adobe illustrator files- are best used for printing as they are vector images and stretch
without getting pixelated or becoming blurry/ unreadable.
PSD files: Photoshop files- PSD is a Photoshop file therefore is a raster/bitmap file extension that is
used for raster images that are created using Adobe’s Photoshop software.
Tiff file- Tagged images file format (TIFF) is used mainly to exchange documents between different
applications and different computer platforms. This file format supports Photoshop quite heavily
and supports bitmap and raster images.
PNG- Portable network graphic employs lossless compression and was originally created to be and
updated and better version of the GIF file format, these files are perfect for uploading to the web
because they are a network file.
BMP- this is a bitmap file format and is used to store 2D bitmap and raster images, independently on
a display device. It’s capable of storing a 2D image with random width, height and resolution. And
both greyscale and colour images.