If you want to buy a new projector for a classroom, meeting room or even a home theatre, the image you project on the screen should make a great impression on your audience.
Researching projectors can be confusing, with many acronyms and technical terms. Highline Office Technology’s projector guide will help answer common questions regarding terminology, features and other important considerations when choosing a projector that meets your requirements.
Colour Brightness and White Brightness
Projectors come in a wide range of brightness which is measured in lumens. The brighter the projector the higher the lumen rating; the higher the lumens, the higher the cost involved.
When shopping for a projector, be sure to look for two-lumen specifications: One for colour brightness and one for white brightness. There can be major differences among different projectors and brands, so colour should be measured and listed separately to provide accurate information. If the information provided only gives you a one-lumen rating, it is typically referring only to the white brightness of the projector. The actual brightness of colour may be as little as one-third of the lumens stated. All Epson projectors, as an example, specify white brightness using ISO 21118 and colour brightness using IDMS 15.4, to make it easy to compare projectors. If you are going to be projecting colour images, be sure to look for a projector with a high colour light output.
The amount of brightness you need is determined by the room you project in. Projector brightness is measured in lumens.
- For home theatre projectors where ambient light is kept to a minimum, you’ll need a minimum of 1500 lumens.
- For classrooms, conference rooms or rooms with windows, a projector with a minimum of 2500 lumens is best.
- For large auditoria or lecture halls, you’ll need more lumens, 3000, 3500 and 4000 are pretty standard these days.
The contrast ratio is the difference between light and dark on a screen expressed by a number. If you take the brightest white on a screen and the darkest black and compare the luminosity, you will get the contrast ratio. For example; 1000:1 contrast ratio means that the brightest white is 1000x brighter than the darkest black.
Therefore, a high contrast ratio means the projected image will have an incredibly rich, crystal-clear detail. Contrast is especially important for the home theatre, where ambient light might otherwise prove it to be challenging to see rich cinematic content if there is not a significant enough difference between whites and blacks.
Epson’s exclusive Vertical Alignment (VA) LCD technology provides an opaque black to be the natural state, allowing a projector to achieve astounding blacks with a contrast ratio up to 200,000:1.
By Jean Evans
See Full Story at www.wibn.co.uk