Having lots of fun with your pc? We reckon you’ll have
even more with a good screen .
We’ve said it before, we’re going to damn
well say it again, and we’re going keep saying it over and over until somebody
starts listening. By far and away and without a shadow of a doubt, the best
long term investment you can make for your PC is a decent screen. Repeat, LCD.
Screen.
That’s especially true at the top-end of
the market, where some specs have stagnated. Back in 2006, the pinnacle of PC
screendom was 30 inches and a native resolution of 2,560 x 1,600. Fast forward
to the dawn of 2012 and absolutely nothing has changed. That’s still as good as
it gets.
In fact, if anything, prices of premium
panels have hardened. Premium 24-inch monitors based on the better VA and IPS
panels are quite possibly more expensive than they were five or six years ago. The
problem is the market for higher-priced panels - there isn’t one. People buy
almost purely on price; they just want cheap and cheerful.
That said, this obsession with cheaper
screens means the focus is on squeezing the most out of a sub-$480 budget. Today,
that figure doesn’t just secure full HD resolutions and stretch to 27-inch and
even 28-inch monitors, it also bags you a multi-function monitor packing
everything from an integrated TV tuner to full stereoscopic 3D support using
the technology of your choice.
UntiL recently, what you wouldn’t get was
anything other than TN technology for the panel, but there are now some
exceptions. Along with some affordable VA panels, the new kid on the block is
e-IPS tech, which is effectively a cheaper version of the IPS screens favoured
for their colour reproduction and found in many premium devices including, yes
you guessed it, Apple’s iPhone and iPad gadgets.
As for the TN masses, the good news is that
the technology continues to improve, closing the gap with IPS and VA. It’s also
worth noting that the increasingly widespread use of LED backlighting, even at
the arse end of the market, has given TN a kick up the backside too. All of
which means there’s serious value to be had if you know what you’re buying, which
is exactly where this month’s LCD panelfest comes in. Every screen purchase
should start from a position of informed awareness. You need to know what
you’re buying and that means getting to grips with the different panel
technologies. Yup, we have been here before, but given the lengths some monitor
makers go to obscure and obfuscate the underlying technology, it’s more
critical than ever to know your TNs from your PVAs.
Twisted Nematic
From the top, the cheapest and most
commonly used panel tech is our old friend TN. Otherwise known as ‘twisted
nematic’, in layman’s terms the thing that really matters about TN technology
is that the liquid crystals in each picture cell are effectively fixed at one
end. When an electrical current is applied, the crystals twist rather than
rotate.
This explains TN’s strengths and its
weaknesses. The tension involved in twisting crystals in one direction means
they pop back the other way more rapidly. The result? Fast pixel response. Of
course, with one end fixed, you never get the full rotation achieved by other
LCD tech, which means light isn’t managed as accurately or blocked as fully.
Result? Inferior colour accuracy, less expansive viewing angles and poorer
contrast.
One of the specific consequences of the
restricted crystal articulation is the need for dithering. TN panels can’t
natively display as many colours as IPS and VA screens. The solution involves
forcing pixels to jump rapidly between two colour states in order to fool the
human eye into observing a third, incremental colour. In theory, it should be
invisible. In practice, it’s sometimes possible to see the pixels fizzing away
as they hop between colours.
Everything is relative though Ongoing
Improvement of TN technology has given us panels superior in some regards to
IPS panels of six or seven years ago. What’s more, it’s not just the panel
technology that has improved. The market-wide shift from CCFL backlights to LED
technology has been a big help for TN screens. You get a broader spectrum of
light, which helps compensate for the inherently poor colours. So, TN monitors
with LED backlights are more vibrant and sock you with more saturated colours.
Yay!
Despite all of this, there are limitations
to TN, and they can be spotted on the spec sheets. That’s true even when the
monitor maker doesn’t deign to mention the panel type. Unfortunately, that’s
pretty frequent. Anyway, the markers you’re looking for go something like this.
Start with the viewing angles, the metrics manufacturers use vary, but if
either figure is under 1700, you’re looking at a TN. Typically a vertical angle
of 160° really gives the game away.
The other major give away is contrast. The
tricky thing here is that dynamic contrast — in other words, contrast achieved
by modulating the backlight - is often the only figure quoted. Any figure of
roughly 5.000 to one or greater will be the dynamic rating. If it’s lower than
that, it’s likely to be contrast with a static backlight.
