BenQ SP840 review

Kat Orphanides
17 Feb 2011
Our Rating 
Price when reviewed 
inc VAT

The SP840 is clearly designed for use in well-lit public areas, but the rainbow effect and high price were more than enough to put us off.



1,920x1,080 resolution, 4,000 ANSI lumens, 90x235x254mm, 3.4kg

The BenQ SP840 is a stunningly bright projector with a 4,000 lumens lamp. It means that you should be able to use it in any room without having to dim lights or close curtains. This brightness also makes the SP840 far more suitable as a living room TV substitute than most projectors, which require relative darkness to be easy to watch. However, it would appear that the projector lamp that burns twice as brightly really does only burn half as long – the estimated life span of the lamp in standard mode is just 1,500 hours. This makes it more expensive to run, too, with a standard hourly cost of 15p, which drops to 11p (2,000 hours) in Eco mode.

The SP840 has a few extra inputs above and beyond what you’ll usually find on a cheaper home cinema projector. There are the usual dual HDMI ports, VGA port, component, composite and S-video inputs, but there’s also a monitor output, allowing you to view what’s happening on-screen even if you can’t see the projection from where you’re standing. This makes this projector a good choice if you need a projector for work as well as home.

BenQ SP840 rear

The remote control looks tacky with its silver metallic finish, but it's comfortable to hold and has a built-in laser pointer. Unfortunately, the projector's IR receiver isn't very sensitive, so the remote needs to be pointed straight at the projector to work.

The SP840 has a clear and simple menu system. The Picture menu lets you select the projector’s colour mode and also set brightness, contrast and gamma; further submenus allow you to control tint, sharpness, saturation and colour levels. Other menus provide options that allow you to turn the built-in speaker on and off and control its volume, perform keystone correction, choose your aspect ratio and flip the display to make it viewable when the projector is mounted on the celling.

There are three default picture modes: cinema, dynamic and standard, plus three user-definable modes. Standard mode was our favourite, with balanced but vibrant colour, rich blacks, subtle gradation and stunning highlights. Cinema mode is darker, and has excellent contrast but more muted colours. These can easily be used to create user colour profiles that you can tweak to your heart’s content. Dynamic mode just annoyed us with its fluctuating brightness levels.

BenQ SP840

Unfortunately, all modes were rather prone to the rainbow effect, even during fairly bright and evenly list sequences. We were impressed to find that there was next to no motion blur in any of our moving image tests, from real-world sport to challenging sequences of still images being moved around the screen at high speeds. The projector is, of course, also remarkably bright, which is very welcome if you’d rather not sit in darkness.

However, the very obvious rainbow effect detracted from our enjoyment and although the projector’s brightness is very welcome, £2,000 is a lot to pay for a single-chip DLP projector. We’d rather spend the money on a good LCD model and draw the curtains. Panasonic’s outstanding PT-AE4000E is much less bright, at just 1,600 lumens, but its picture quality is well worth the compromise.




Projector technologyDLP
Lamp brightness4,000 ANSI lumens
Lamp life1,500
Lamp life in economy mode2,000
Contrast ratio3,000:1


Native resolution1,920x1,080
Max compressed resolution1,920x1,080
Aspect ratio16:9
Other aspect ratios4:3
Max diagonal at 7ft55in
Throw ratio1.59:1 to 1.9:1
Optical zoom1.2x
Mirror imageyes
Invert imageyes
Lens shift horizontal0%
Lens shift vertical0%
HD Readyyes
Special view modesdynamic, standard, sRGB, cinema, 3x user


VGA inputyes
DVI inputNo
Sound inputs3.5mm
Composite inputyes
S-video inputyes
HDMI inputyes
PAL supportyes
SECAM supportyes
NTSC supportyes
Audio output3.5mm
Video outputVGA
Others inputs/outputssecond HDMI input, RS232


Noise (in normal use)39dB(A)
Internal speakersyes (3W mono)
Extrasremote, carry case, cables (power, VGA)
Remote special featuresbacklight
Power consumption standby0W
Power consumption on352W


Lamp cost (inc VAT)£226
Lamp cost per hour of use£0.15
Lamp cost per hour of use (economy)£0.11

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