Digital Camera Photography
How is it that a photograph taken with a traditional 35mm Camera and film always came out perfect and yet when I
use Digital Camera Photography and the same techniques with my Digital Camera, the photo's always
seem a little less than perfect.
After all, when I took the photograph, it looked great in the LCD viewfinder - light bright and in focus!. Are
the wonders of modern technology conspiring against me or am I just assuming that Digital Camera
Photography and Digital Cameras work exactly the same way as my 35mm traditional camera.
Although Digital Cameras are a revolutionary new way to take pictures, they are very much based on conventional
photography and uses many of the selfsame principals. Both types of photography require a lens to focus the light
and a shutter to allow the light to pass into the camera. One of the main differences between digital and
conventional photography is the technology used to capture the image..
Conventional photography uses film which must be developed in a darkroom in order to produce negatives which
than must be printed in order to see the photograph. Digital Cameras on the other hand utilises an electronic
sensor to capture the image. The sensor is made up of millions of individual picture elements commonly known as
pixels which convert light into a number. Rather than waiting for the picture to be developed and printed, Digital
Cameras pictures can be seen almost immediately on their built in display or the viewfinder.
Digital Photo Resolution
Depending on how many pixels a digital photograph consists of will determine the ultimate quality of that
picture. The resolution of any image is directly related to the number of pixels that make up that image. For
instance, a common resolution for a computer screen is 800 x 600 meaning that the monitor can display 800 pixels in
width and 600 pixels in height giving a total of 480,000 pixels. Image resolutions in digital photography are much
higher than than computer monitors with numbers in the millions of pixels or mega-pixel range. A digital camera
with a resolution of 2048 x 1536 would have a total resolution of 3.1 million pixels or mega-pixels .
Each individual pixel is represented by a number. and the size of that number will determine the colour scale
that can be represented. For instance, a black and white image can be represented with pixels which are just eight
bits in length. If you are at all familiar with binary mathmatics, you will know that an 8 bit number can represent
decimal numbers from 0 to 255 with 0 being black and 255 being white and all numbers in between representing shades
of gray.
Colours on the other hand must be represented with larger numbers. For instance, a colour scale of 65,536
different shades would need to have 16 bits per pixel and 24 bits per pixel would represent more than 16 million
different colours. The majority of consumer orientated digital cameras use 24 bits per pixel, whereas professional
equipment can have a colour resolution of up to 48 bits per pixel for more than 280 billion different colour
shades.
Although there are several variables that affect the quality of a digital camera, the pixel resolution is
generally seen as being the most important. Depending on the size of photographs that you want to print will
determine the pixel resolution of any digital camera that you might purchase. Another consideration to bear in mind
is that as the number of pixels in any digital image is fixed, the more the size of a photograph is increased the
less the number of pixels per inch. Consequently, if the image is enlarged beyond the standard of 300 pixels per
inch the resulting clarity and sharpness will be reduced.
Digital Photo Printing
Photo processing outlets normally print pictures at 300 pixels per inch. Using this figure as a benchmark will
enable you to calculate how many mega-pixels your camera should have. Photographs from cameras rated at two
mega-pixels can be printed as large as 5.8" x 3.8" at 300 pixels per inch, whereas a four mega-pixel camera can
print photos as large as 8.2" x 5.4" also at 300 pixels.
You can still print larger photographs but it should be bourne in mind that pictures printed at say 200 pixels
per inch would be slightly less sharp but still quite acceptable for most purposes. With a resolution of 200
pixels, maximum picture size of 8.7" x 5.8" would be possible from a two mega-pixel camera, and 12 .2" x 8.2"
prints from a four mega-pixel camera.
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