The Panasonic PT-LB51EA is small enough to cart around and designed to cope with well lit rooms. All in all, it is a usable machine with an attractive price tag.
Projectors are placed at a distance of three metres from a test screen and zoomed to a screen size of 100 inches where possible. (We calculate expected brightness at 100 inches if this size is not achievable.) Brightness is measured around the screen in order to determine average brightness and variance. We also use a chequerboard pattern to measure the contrast ratio of black to white regions. Ambient light is subtracted from all brightness measurements before any comparisons are made.
DisplayMate software is used to assess colour quality and sharpness of static images. We also consider the performance of the machine with video output. Fast action and animated films are used to assess refresh times, skin tones, solid and graded colours and borders.
We assess the useability of the device including menu use and options, set-up, and connectivity options. Fan noise is also a consideration.
Design and features
Weighing in at only 1.8 kilograms and having an A4 paper size footprint, this machine is truly designed to be portable -- and in case there is any doubt it comes supplied with a carry bag. The casing is silver with a pale grey base and all controls are on the top surface (bottom if you choose to mount it permanently on a ceiling). The air filter is very easily removed and access to the lamp is also quite simple. Four ordinary screws and a plug are all that secure the lamp housing.
The machinery inside is a triple LCD. Such machines generally have very good screen refresh rates, but can suffer a little in terms of contrast when compared to the competing DLP technology.
This is a standard screen ratio projector (4:3) with a resolution of 1024x768 pixels. While not spectacular it is quite adequate and the ease of transporting and setting up the projector in new locations will more than make up for a less than state-of-the-art screen resolution. There is also a handy digital zoom function (x3) and a small built in speaker.
Flexibility supposedly extends to a multilingual menu system, but we fear the manufacturers were not overly thorough in their implementation -- various menu items remain in English when other language options are chosen and extended-Latin characters seem not to be available for those languages that require them.
Transmitting data to the projector is a simple affair. A VGA cable is supplied for PC/notebook support or alternatively there is one each of serial, S-video and composite video ports. Stereo RCA audio input is present along with standard PC input/output jacks. A second VGA port can be used for either input or output to an auxiliary monitor.
The remote control has well spaced buttons with large lettered labels. The on-screen menu is reasonably easy to use and common functions have dedicated buttons on the remote (eg: freeze, zoom and input selection).
An interesting feature of the Panasonic is "Daylight View 2", intended to enhance viewing clarity in well lit areas. Ambient light is measured by the machine and adjustments, such as exaggerating the contrast, are made to make images more accessible. In practice, Daylight View did not appear to make a huge difference to image brightness; nonetheless, the projector did perform adequately in a lit office. And after the presentation if you need to make a quick getaway, you can simply unplug the power and start packing the machine up -- onboard power will keep the fan running until the lamp has had a chance to cool.
Colour reproduction was good in all colours including skin tones. A minor issue was the imperfect alignment of the LCDs causing slight magenta and green borders around pixels and objects, but this was not apparent from a normal viewing distance.
Our measurement of the contrast ratio was disappointing -- even in comparison to other 3LCD devices (22:1 on our chequerboard test screen). The image appeared crisp and screen update rates were great during fast movie action. Variance in brightness from centre screen to the periphery was a little poor at 12 percent, but again it detracts little from the viewing experience.
Considering this is such a small machine, it is surprising that it is capable of a big 100-inch picture at only three metre distance from the screen. Our biggest beef about this product is the cooling fan -- you will want to plug in some external speakers and turn them up loud! Reducing screen brightness with "eco-mode" did little to improve noise levels. More positively, the machine has good colour and is easily moved to new locations for use in a range of lighting conditions.
Customers have access to a free customer support line and there is a two year warranty on the machine. Lamp life is shorter than some with a maximum life of 2000 hours. A lamp guarantee also applies which protects your lamp for 500 hours or three months. Running costs are about 32c/hour, with replacement lamps costing around AU$600.