Webuser Forums: Powerpoint Presentations

There are quite a few criteria that determine what makes a suitable projector.

1 Portability

You need something that isn't too heavy and bulky. You can get projectors that are designed to stay in the classroom/office and thus are more difficult to move around.

2 Brightness

Projector brightness is measured in lumens. If you wanted one for home use to display TV/VCR pictures than because you can make your own room dark, a machine of 900/1200 lumens is probably good enough. If you will be using one in various locations where the ambient light level cannot be controlled to such a degree you should be looking for one that uses 1500 to 2000 lumens. They are available at even greater levels of intensity but then the price starts getting silly.

3 Contrast

The higher the contrast the better the picture 'depth' and colour display. Anything better than a contrast level of 1000:1 is good.

4 LCD or DLP

LCD is Liquid Crystal Display and DLP is Digital Light Processing. You can only get contrast levels of up to 800:1 using LCD but up to 3000:1 with DLP. DLP has the added advantage of not having any 'dead' pixels. If you would like to know how it works, have a look at this.

5 Aspect Ratio

Standard computers use an aspect ratio of 4:3. Wide screen TVs and PCs use an aspect ratio of 16:9. To get a projector that has a 'native' resolution of 16:9 is a lot more expensive. Most projectors can handle 16:9 by 'letter boxing' the image, leaving a black band top and bottom.

6 Resolution.

XGA is superior to SVGA as it displays about 63% more pixels. SVGA is acceptable but XGA is better.

7 Bulb Life

The cheaper projectors are only cheap because they use cheaper bulbs. A replacement bulb can cost anything up to £350! The cheaper end of the market have bulbs that can only be set to one intensity and have a maximum life of 1500 to 2000 hours. The better quality projectors have two levels of intensity, standard and economic mode. Economic mode should offer a life of about 4000 hours. You can define the mode when using the projector based on the ambient light in the room in which you are doing the presentation. If it's properly darkened then you switch to economic. If it's difficult to see the pictures on screen then switch to standard.

8 Price

Ideally less than £500. The most expensive one I've found so far was £3,650!

Hope that helps you to choose what's right for you.

--------------------

Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.