Feeds

How to choose the right screen size

Is your telly too small - or too big - for HD?

3 Big data security analytics techniques

The maths bit

That all assumes the 2.7m viewing distance - if substantial numbers of people really are viewing HD sets much closer than that, perhaps the BBC will need to rethink the decision to broadcast its HD programming at 1440 x 1080 rather than a full HD.

Panasonic

Glasses won't help if you're too far away...

Not everyone’s watching BBC HD, and for many of us, an HD TV is also something to use with games, or for watching Blu-ray and other high definition content. And the real question, rather than ‘what resolution do we need to broadcast’ is ‘how far away should I sit from my TV?’

If you’re interested in working out the answer to that question, it’s not that difficult. I’ve made some assumptions here, chiefly that you have good or corrected eyesight, and that your TV set has an aspect ratio of 16:9.

In fact, the important measurement is really the height of the picture, or H. For a 16:9 screen with a diagonal picture of size D, you can calculate H using Pythagoras:

Formula 1

The generally accepted figure for human visual acuity is one minute of arc, so we need to calculate the distance at which one pixel is equivalent to that.

The simplest way to approximate this is with a triangle where the vertical side is the height of a pixel, p, and the other sides are of equal length. Bisect that triangle at the centre point, and we have a right angle triangle, with the angle at the eye equivalent to 30 seconds of arc, and the distance to the eye is d. A bit of basic trig gives us our next formula:

Formula 2

SANS - Survey on application security programs

More from The Register

next story
Samsung Galaxy S5 fingerprint scanner hacked in just 4 DAYS
Sammy's newbie cooked slower than iPhone, also costs more to build
US mobile firms cave on kill switch, agree to install anti-theft code
Slow and kludgy rollout will protect corporate profits
Leaked pics show EMBIGGENED iPhone 6 screen
Fat-fingered fanbois rejoice over Chinternet snaps
Oh no, Joe: WinPhone users already griping over 8.1 mega-update
Hang on. Which bit of Developer Preview don't you understand?
Microsoft lobs pre-release Windows Phone 8.1 at devs who dare
App makers can load it before anyone else, but if they do they're stuck with it
Report: Apple seeking to raise iPhone 6 price by a HUNDRED BUCKS
'Well, that 5c experiment didn't go so well – let's try the other direction'
Rounded corners? Pah! Amazon's '3D phone has eye-tracking tech'
Now THAT'S what we call a proper new feature
Feast your PUNY eyes on highest resolution phone display EVER
Too much pixel dust for your strained eyeballs to handle
Hearthstone: Heroes of Warcraft – A jolly little war for lunchtime
Free-to-play WoW turn-based game when you have 20 minutes to kill
Zucker punched: Google gobbles Facebook-wooed Titan Aerospace
Up, up and away in my beautiful balloon flying broadband-bot
prev story

Whitepapers

Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
SANS - Survey on application security programs
In this whitepaper learn about the state of application security programs and practices of 488 surveyed respondents, and discover how mature and effective these programs are.