|
<loc>http://www.projectionlogic.com/index_files/Page655.htm</loc> |
|
|
|
|
|
SHEDDING THE LIGHT ON PROJECTION |
|
What is Contrast Ratio and How is It Measured?
Contrast Ratio is the ratio between white and black. The larger the contrast ratio of a projector the better ability it will have to show varying shades of color in more detail and compensate for ambient light. It important when comparing contrast ratios amongst projectors that you are using the same type standard. The most common standard is set forth by ANSI. A pattern of 16 alternating black and white rectangles are projected on a screen, an average rating is taken from the white squares and divided by the light output of the black; the result is shown in a ratio. The less common method is referred to as full on/off. This method takes one reading from a pure white image and divided by a reading from black image. The result of this method is not as accurate and is usually higher than the ANSI standard.
Contrast being tested using the ANSI standard.
Is a High Contrast Ratio Better Than a Low One?
Yes, a higher contrast ratio will give you the ability to adjust for ambient light and when adjusted right will give you a better looking picture. Be careful when comparing contrast ratios. Some projector manufactures use different methods to test and rate their projector’s ability, causing an unfair comparison of data.
The image on the right has a higher contrast ratio. |
