LED screens and pixel pitch

As the cost of new event technology comes down, LED screens are becoming more popular locally… And while there is still a cost consideration, they offer massive advantages over traditional projection. When using projection, one needs to ensure that the ambient conditions are suited to the size (light output) of the projector. Very often, this requires venues to be blacked out with draping – which obviously adds to the cost of your event. Many indoor venues don’t necessarily have this issue, but then your lighting designer/operator needs to be careful as to how to light the event, so as not to wash out the information on screens.

Projection has a fixed format – these days the accepted format is 16:9 – but by blending a number of projectors together (at cost) this format can be “altered” but takes time, a specifically manufactured custom ‘non-format’ screen and a skilled technician to effect properly.

This article, however, is about LED screens, its advantages and the dreaded “pixel” display conversation.

The first set of advantages is in how an LED screen is put together.

LED screens are made of panels. Panels vary in size (physical size) depending on make and manufacturer, but save to say, panels are locked together to create the size screen and shape that you require. 16:9 formats need no longer be the standard because you can create any size or shape that you or your designer would like to see. Certain makes of LED screen can be locked together at angles, creating curves, circles or almost any shape you like. In fact, you may be able to replace a traditional set element with a funky digital LED set.

LED screens are brighter than projection, so don’t have the same ambient lighting issues to contend with, and can be used outdoors in sunlight very effectively.

On to the pixel debate…

All LED screens are measured/quoted or spec’d in pixel pitch. You may not inquire of your supplier, or they may not be forthcoming with the information – but a reliable supplier will specify the right screen for the right job.

 

You will know what the pixel pitch is when you read something that mentions dimension in millimetres (mm). Some common industry pitches at the moment are for example – 3.2mm / 3.6mm / 6mm / 10mm and upward.

What does this actually mean?

As mentioned previously, LED screens are made up of panels. These panels have a large number of LED “dots” (pixels) on them (if you get up close to look) these dots – or LED’s (light emitting diodes) are what actually make up the image which you want to see. Because not all manufacturers make panels the same physical size, the number of pixels per panel may vary, but the important thing here is the measurement in millimetres from one pixel on the panel to the next. The closer they are together – (3.2mm is closer than say 10mm) the better the quality of the image – so it’s correct to say that the smaller the measurement, the higher the quality or resolution. Pixel pitch is, therefore, the distance between pixels on the panel, and the spec by which most people in the industry will work.

Picture quality is not always as simple though, as there are other factors to consider. Contrast ratio’s, brightness of the screen and so on, but using the above as a general rule should suffice (the other bits are really for your AV team to consider when deciding what screens to invest in)

But wait – there’s more…

What do you need for your event?

The distance the first row of your audience is seated from the screen should be a consideration – because this will affect what you need, and possibly your budget.

General rule #1

1mm of pixel pitch for every 1m from the screen. If you have a 3mm screen, you could sit as close as 3m and still see the content pretty well. 6mm pitch = 6m, and so on.

I would seriously caution against applying that rule across the board and assuming that because you’re in the Superbowl, and your closest audience is 20m away that you come to blows with your supplier in the pursuit of a 20mm pixel pitch. Technology has moved on, and those old screens really do not exist much beyond a dusty warehouse…

 

 

General rule #2

Higher pixel pitch = more money

Your content will help inform the decision too.

Financial results with serious graphs and bar charts will need the highest resolution you can afford. Because it’s your companies best foot you’re putting forward, and you want the analysts to see the detail.

Background graphics behind the DJ at the company shindig… not so much.

So what’s the debate?

On the international market – screens are being manufactured as high as 0.9 mm. You could almost lick the screen while watching your content and still see what’s going on. But if you’ve got 500 people in the convention centre sitting arm’s length away from your screen, conceptually, there are other issues to discuss.

Locally, 2.9mm and upwards are being spoken about. While that’s a great picture, is it really necessary to pay for that resolution when something else will do? Of course, it would be great to pick up a C63 AMG convertible when you land at the airport, but my guess is a group A or B does just fine.

While you can tell the difference from a distance between the C63 and a VW Polo, can you do the same from across the room between a 2.9mm screen and a 4.8mm? Thought so.

A caveat to rule #2

Like all things electronica, the Chinese manufacturing machine churns these things out for fun. Unfortunately, not all 5.9mm screens are the same as all 5.9mm screens…

There are always cheaper options available, and these are apparent in the build quality and reliability of the screen. The locking mechanisms may not give you a completely seamless image, and often you can see gaps in the panels. Colour differences from one panel to the next may be a problem. Panels may fail at a critical moment, and a number of other issues may arise when you least expect or want them.