Which LED screen is best for your church? Part I - Pixel Pitch

So you’ve jumped into the broad, vast, and sometimes quite scary world of LED display technology, there are so many options and you’re wondering ‘what option is best for me?’. If you are installing a video wall inside your church, there are a few things that we think you should take into consideration in order to make sure you get the best fit for your install. We’ve split this blog into a few sections and will post updates in the coming weeks

Pixel Pitch

Pixel pitch is one of the first things you’ll hear being discussed when looking at LED displays, and it’s very important. The pixel pitch relates to the distance between each pixel. The lower the pixel pitch, the more pixels per panel, which results in a higher quality image. So a screen with a pixel pitch of 4mm will produce a higher definition result than a screen with a pixel pitch of 6mm or 10mm. Higher quality is always what we want to aim for, but there are a few things that effect choosing the right pixel pitch for your application.

Distance

When choosing what pixel pitch to aim for, distance to the front row is one of the most important factors. Viewing distance is roughly 1mm to 1m, so a minimum ideal viewing distance from a screen with a 6mm pitch is roughly 6 metres. I should note that at 6 metres you will still see SOME pixelation of a 6mm screen, as it is the MINIMUM ideal viewing distance, but it will begin to disappear. 

Cost

As the pixel pitch decreases, the cost increases. This is obviously a very important factor, but you might be surprised at what’s available in your budget. There is a tipping point in any technology where it gets exponentially more expensive, but we have found that the price jumps from 6mm->4mm->3mm and even to 2.5mm screens are quite reasonable as they now sit in mass produced sizes. When investigating a creep for your application, definitely ask for some prices on different sizes, so you can see what the cost difference is. 

Content

What content are you running on the screen? This is often not taken into consideration when choosing pixel pitch, but it is a really important one to talk about. Say you make the decision to invest significantly in a LED display and opt for a large format 10mx4m screen with a 3mm pixel pitch. The screen looks glorious in demo’s but whenever your video switcher puts content on it, it looks a little blurry? Why is that? Well you’ve moved past the realm of true HD towards 4K quality, but your video switcher hasn’t changed with it. If you are only going to be sending a 1080p signal to a screen that has a resolution of over 3k, you’re having to upscale the content to fit the screen, and each beautiful little pixel isn’t getting used to it’s maximum capacity. There are solutions around this and we’ll talk about them another time, but remember the same logic works in your home: there’s no point buying a UHD 4K display if you’re just going to play your old VHS collection on it.

Dave

Trouble shooting LED displays

“Data” or “Power”. If you are having problems with an LED display, it’s likely to be related to one of these two things. LED screens are great when they work, but if they stop working, they become a stressful eyesore. If you’ve got an LED display in your church, shop, business etc, you need your problems fixed quickly, and calling an in tech support can often be costly and unproductive.  All LED displays work by daisy chaining data and power between multiple smaller LED sections (called cabinets), contained in these two cables is everything that is likely to go wrong with your screen. These are five common problems we’ve seen that are easy to fix yourself when you know how. 

The whole screen is blank but the power is on

Data! If your whole screen is off, but you’ve checked your power, it’s most likely a problem somewhere between your sending card and your first cabinet. Check to make sure that the cat6 cable is plugged in at both ends, and if it is, try a diffent cat6 cable. If there is still no picture, try plugging it in to a different panel and see if you get a different result. If there is still no picture, you might need to check/replace your sending card. 

A section (multiple cabinets) of my screen is blank

Probably power. Because LED displays draw a lot of power, it is really easy for them to trip their circuit in the power distributor. Great news is that you are using high quality sending and receiving cards, the data will keep running through to the next powered up cabinet, even if some of them have power off. Check the back of the cabinet for power lights, if they are off, go and reset the circuit. if the power lights are on, check the data cables surrounding the first blanked our cabinet, it’s possibly a loose data connection.

There is a cabinet in my screen that is intermittently flickering

Data. This problem is most likely a faulty daisy chained cable or a dodgy connection into (or out of) the cabinet. I had an infuriating time trouble shooting a client’s panel recently when I triple checked (and checked again) data and power. It looked like a data problem, power supplies and lights were all consistently on, but a cabinet would intermittently drop out or flicker. I finally got to the point where I was about to start replacing parts, went to take the receiving card out and it practically fell out of its contacts. This problem was ultimately a data problem, the receiving card wasn’t properly seated and needed to be pushed in properly. Once the receiving card was properly seated, the cabinet worked flawlessly. 

There are black lines or lines of discolouration across my modules

Data. When you don’t know what’s going on, this is not a good feeling, but don’t freak out, it’s easily fixed. This problem can be a little more frustrating because it might mean replacing a module or a ribbon cable depending on the style of LED cabinet you have. The photo on the left is a style that needs a ribbon cable. If you’ve got a single module that has striped black lines across it, you probably have to replace that module (or make sure it’s properly seated). Just open up the back of the cabinet, and swap out a ribbon cable with your spares (which you should have received with your LED display when you bought it) and you should be back to normal in no time.

Sections of my LED screen are different brightnesses!

Data. Now this is especially common if you are using the screen for rental purposes and pulling it apart often to set it up in new configurations. If you have whole sections of your display that are different brightnesses, you don’t have a calibration problem, it’s most likely just a software brightness setting. Open up your control system (we use Novastar), select brightness, then choose a brightness and click save to hardware. There you have it, you’re screen should now all be a consistent brightness again. 

Remember, LED screens are designed to be simple, so assuming you’ve purchased a high quality display, trouble shooting problems should be simple. Hopefully that was helpful to someone, let us know if you have any other common problems or anything you would like to know about LED video displays. 

Dave

dave@churchled.com.au

Creative possibilities with LED displays

So often what we 'don't know' holds us back from what is possible. It can be hard to imagine that LED panels could be more than a rectangular box, but the possibilities have grown by epic proportions in the last few years. With an ever decreasing pixel size and new technology being developed all the time, multi modal advertising with beautiful clarity are now within reach. 

The Australian market is ready for some new innovation, have a look below at some options that are possible with LED design.

Think outside the box 

There's more to LED displays than squares and rectangles, we would love to partner with you to create something beautiful. Maybe you have an application that one or more of these elements could work for. Get in contact with us and let us know if we can help!

Dave

dave@churchled.com.au