Thursday 6 May 2010

Pixels, Resolution and Vector Images


Pixels
Small dots or pixels (picture element) are the basis for any image. A pixel is split into sub-pixels of red, blue and green. Pixels add together to make a bitmap image, a grid that resembles a mosaic of dots. The size and proximity of pixels will determine the quality of image, smaller and closer together will give a higher quality image. As any image is magnified, the size and proximity of the pixels increases so producing a distorted image with blurred integrity that produces inferior graphic results. You can test this by zooming in on a picure and the pixels or building blocks will become apparent.

Bit-Depth
This is the amount of digital storage space that is used to record information about a pixel.
The more bits you use, the more information to describe the colour of a pixel can be stored.

Resolution
In graphic design one of the key elements is 'resolution'. This is measured in pixels per inch/dots per inch (dpi). To achieve a strong image, a high resolution image is needed. Taking any pixel image and doubling the size to will half the resolution, blurring the image. In order to ensure good print quality, any image used should be 300 dpi. The only exception is for web images where 72 dpi is sufficient, the same as screen resolution.

Vector Images
Vector graphics use shapes, points, lines and curves combined and stored as a mathematical formula to create an image on screen. When increasing magnitude of an image, the vector formula is used to reconstruct the screen image, allowing the images to be scaled up and down and still producing the best image with highest quality resolution. This will result in smooth and crisp printing.

our favourite free vector images

Using vector images in graphic design is very specific, not always suitable for corporate design work, but very beneficial for 'glamming up' a design.

Vector graphics are available to download for free from the following sites:
Vecteezy
Greepit

1 comment:

Jenny Poile said...

Very informative article and amazing website. I haven't used vectors much in the past but at least I understand them now.
Thank you