Labs

Business projectors

In this test, we're looking for the best-quality business projector under £800, which means that, although there are portable products here, most manufacturers have gone for image quality and features over lug-ability. Despite the fact many of the projectors we've tested come with carry cases and could feasibly be considered as a companion to a notebook, their bulk means most are intended for permanent installation or single-building use.

Brightness, quietness and image quality are essential for a projector such as this, which is likely to be used in a variety of locations, from small meeting rooms to large boardrooms and classrooms, and for displaying all sorts of content, from static slides to movies.

To reflect this diversity of applications, we rate each projector's performance in a wide range of exercises, involving both objective measurements and subjective ratings. From these results, we calculate five star ratings: Image Quality, Features & Design, Quietness, Value for Money, and then an Overall score.

Image Quality

All the projectors on test are capable of projecting a bright, colourful XGA image, but some produce a better picture than others. One factor affecting this is whether the projector uses LCD technology or the newer DLP system. But, from a buyer's perspective, what happens under the bonnet is irrelevant, so in our tests we focus on the results.

To prepare for the testing, each projector is set exactly 2m from a projector screen, with no keystone correction and the zoom set to the widest position. The room isn't specially darkened, but the screen is shielded from direct sunlight. The projector is set to factory defaults, with economy mode disabled, and connected to the VGA output of a laptop and configured as a clone display. The lamp is allowed to warm up for five minutes before testing.

For the first stage of our quality test, we use DisplayMate (www.displaymate.com) to generate a series of test patterns to expose technical weaknesses and indicate how well the projector locks to the analogue signal. For the next stage, we switch to video or movie mode and play a series of video clips involving bright colours and rapid action. We're looking for smooth movement.

If the projector has DVI, we repeat the tests using this interface and note any improvement, and finally we switch to the video or movie mode and run the tests once more with each projector set on a standard slope of about 10 degrees to enable us to assess the impact of keystone correction on image clarity.

Each projector is assessed independently by two reviewers; selected results are printed below. The combined scores are then weighted according to their relative importance and converted into a rating out of six.

Features & Design

The Features & Design score is calculated by awarding points for the availability of controls through the menu system and remote control, and for hardware features such as the zoom ratio of the lens, the video interfaces supported and the size of the picture at close quarters.

We also consider ergonomics and convenience, such as the unit's bulk and any included accessories. Lastly, we consider the warranty: if you suffer a hardware failure this can have a huge impact on your experience.

Quietness

Operating noise can be an issue when using business projectors because they're often placed near to people who are speaking. In a small room, the noise of the fan that cools the lamp can be intrusive, so it's worth considering.

Manufacturers do cite figures for operating noise levels, but these figures may not be precisely comparable, owing to variations in measuring techniques, and the type and placement of the measuring equipment.

We commissioned Intertek Research & Testing Centre to perform independent noise measurements under controlled conditions. Measurements were taken from a distance of 0.5m from the main fan vent over 10 seconds between the frequencies of 80Hz and 20kHz. The chart above summarises the results (the full technical report is in the Editorial folder on the cover disc). Bearing in mind that the dBA scale is logarithmic, the gap between the quietest and loudest projector is significant, and if you want absolute quiet, it's well worth using each projector's economy mode.

Value for Money

The Value for Money score reflects each projector's price in light of its scores for Image Quality, Features & Design and Quietness. Top marks, therefore, don't necessarily go to the cheapest projector, but to the one that delivers the best performance per pound. This score also factors in the long-term costs of replacing the lamp. We've assumed a usage of 10,000 hours, but this won't apply to everyone, so take your circumstances into account alongside this score.

Overall

The Overall rating is a straight average of each projector's score for Image Quality, Features & Design, Quietness, and Value for Money.