Hmm..GA better than going to school? Looks to me that you just
want an excuse to bunk classes. ;-)
Anyways, its great to have you back. Lets see if we can satisfy
your curious mind this time.
What is a PIXEL?
The name Pixel stands for a PICture ELement. A pixel is a single
point in a graphic image. You can consider it the smallest piece of
information we store about an image. Graphics monitors display
pictures by dividing the display screen into thousands (or millions)
of pixels, arranged in rows and columns. The pixels are so close
together that they appear connected.
When we talk of the resolution, we are referring to the number
of pixels that make up the image. Common screen resolutions are :
640x480, 800x600 etc. As you can see, the resolution is described as
(the number of pixels available horizontally) x (the number of pixels
How does Resolution affect quality?
Simple! Higher resolution = better quality. If you have a
higher resolution image, that means you are using more pixels to make
up the image. More pixels = more information = better quality.
How Many Pixels in an inch?
There is no answer to this question. A pixel has no predefined
size. Think of a pixel as a dot. You can draw a one inch dot or you
can draw a 1 mm dot.
This is why you cannot determine screen size from the screen
resolution. A 14 inch monitor can display the screen at multiple
resolutions eg. 640x480 or 800x600. The size of a pixel displayed by
it at the 800x600 resolution is smaller than the size of the pixel it
uses at 640x480, but the overall screen size(14 inch) remains the
same. As you can see, the number of pixels per inch(ppi) determines
the screen resolution. Higher ppi = Higher resolution
Another thing to note is that the number of ppi(and hence the
resolution) affects the size of the images and text being displayed.
An image of size, say, 100x100 pixels will appear larger at a lower
resolution of 640x480, than at a higher resolution of 800x600, due to
the lower ppi value at 640x480.
A very important component of image quality, is the Colour Depth.
Colour depth can be defined as the number of bits being used to store
colour information for a pixel. The larger the bit depth, the more
colours a pixel can take on. More colours = Better quality. The table
given below shows some of the common colour depths available, and the
number of colours they allow :
Colour Depth - Number Of Colours
8 - 256
16 - 65535
24 - millions of colours
The monitor screen sizes are determined by the manufacturers,
and do not affect pixel size as such. However, small screened monitors
(such as 14/15 inch ones) are not capable of displaying high
resolution(say 1600 by 1024) images, because then the number of pixels
per inch(ppi) will be very large and hence, the size of a pixel too
small to be useful. This is why people prefer large screen (17 inch
and above) monitors.
All the metrics defined above go into defining your picture
quality. A large screen size would mean that even at high resolutions,
the pixel size won't become too small, and this will result in a
Higher resolutions are obviously better, because higher
resolution = larger number of pixels making up the image = Better
Larger colour depth allows your image to have more shades of
colour, thereby improving quality.
So, for improved viewing pleasure, use a large monitor (17 inch
and above), set to a high resolution (1024x768 or higher) and high
colour depth(16 bit or more).
Some extra readings
- Computer Graphica : What Is a pixel ?
( http://www.computer-grafica.com/d16.asp )
- PhotoELF - What is a Pixel
( http://www.photoelf.com/support/faq/pixel.shtml )
- Understanding Monitors:Controlling Pixels, Resolution &
- Screen Size and Resolution
( http://lowendpc.com/tech/resolution.shtml )
Well, hope this helps.
If you need any clarifications, just ask!
Google Search Terms Used :
"What is a pixel"
"what is dot pitch"