Short-Throw Classroom Projector
June 2, 2009
Viewsonic's PJD5351 is a short-throw XGA DLP projector. High lumen output and a short-throw lens make it a great fit for a cramped classroom, especially on a rolling cart. Filter-free design, long lamp life, and inexpensive lamp replacements make it easy to maintain. As if this were not enough to make it a great classroom projector, its sub-$800 price means that it won't break the school's budget.
High lumen output. The PJD5351 is rated at 2500 ANSI lumens. Our test unit measured 2321 lumens in its brightest mode, which is conveniently named "Brightest." This is 93% of the stated specification, and excellent performance by any metric. In a classroom where light control is difficult, a moderate-sized image is bright enough to be seen easily by all of your students. With the lights off, you can make the image even larger, which helps when accommodating larger classes.
Eco-mode, which boosts lamp hours from 3,000 to 4,000, decreases light output by 30% to 1600 lumens. In a room with the lights dimmed, this is still more than enough light to create a bright, vibrant picture.
Good brightness uniformity. Short-throw projectors occasionally have problems with low brightness uniformity, due to the extreme angle at which the light hits the screen. This is not the case on the PJD5351, which maintains 77% uniformity. There is no visible hotspotting, though 77% uniformity means that the viewer can see a brightness difference with the naked eye. As is typical with short throw projectors, the bottom third of the image is the brightest, while the top third is slightly dimmer.
Short throw lens. The PJD5351's claim to fame is its short-throw lens, which can project a 100" diagonal 4:3 image from 5' 10" away. This is not the shortest of the short-throw projectors. However, being farther from the screen helps with brightness uniformity, since the light hitting the screen is doing so at a less extreme angle. Since the projector has no zoom, you'll need to move the projector closer or farther from the screen to adjust image size.
Security. The PJD5351 has the standard attachment point for a Kensington cable lock, as well as the attachment point for an additional cable or bar lock. On a projector so well-suited to use on a rolling cart, having a double measure of physical security is reassuring. The projector also has a control panel lock, but it is not password protected and can be disabled from the control panel itself, making it largely useless. The bottom line here is that you'll have to rely on physical security, because there are no password functions on the PJD5351 that would deny use of the projector to a potential thief.
Blackboard mode. Not every classroom has a screen. The PJD5351 has blackboard mode to compensate for this. Using this setting will alter the color balance of the projected image, in order to make it appear more natural when projected on to a blackboard. It also has settings for green- and whiteboards, which are more common in newer schools.
Low cost of operation. The PJD5351 has a lamp rated for 3,000 hours of operation in normal mode and 4,000 hours in eco-mode. Replacements cost $299. There is no dust filter, resulting in an easy maintenance schedule and low total cost of ownership. One minor annoyance is that the PJD5352 has a bottom-changing lamp, so if you were to ceiling mount it, it would need to be taken down for lamp changes.