To achieve a large image, installers have a myriad of options.
Should they go projection?
This is, by far, the most cost effective and simplest way to attain a large display image, especially if high resolution is required. But is there too much ambient light? Would a high brightness laser projector cut through this?
Should they install a Large Format Display (LFD)?
For a large image a single LFD screen is heavy, cumbersome and expensive. They could create a videowall with multiple LCD screens but this has the downside of bezel frames around each screen slicing through the overall image.
Or they could look at an LED display.
LED displays are made up of slim LED panels installed flush beside each other to create a seamless display with no bezels disrupting the image. They are expensive compared to projection but large LED displays are becoming far more comparable in cost to similar size LFD videowalls.
But which one is best? We catch up with Ross Noonan, Technical Product Specialist at Optoma, to try to cut through the confusion.
Q: So, which solution is best Ross?
A: It depends on the environmental factors.. In a high ambient brightness environment, projection will look washed out but if the ambient light is not too high or light could be controlled, projection may be the best (and certainly the cheapest) option.
If the ambient light is high and you want large seamless imagery without bezels interrupting the image, you may need to look at installing an LED display.
Q: That sounds complicated.
A: It doesn’t need to be. You need to ask more questions perhaps than for a regular projected display but honing down the requirements, by asking a number of key questions, will help you choose the right solution.
Q: What questions do I need to ask when looking at LED displays?
A: Do you need a permanently installed or mobile solution?
Is it for indoor or outdoor use?
How bright is the environment where it will be operating?
What size and aspect ratio do you need?
What content will you be showing?
Where will the audience be in relation to the display?
How accessible will the display be if it needs maintenance?
Q: Can you use LED displays in full sunshine?
A: Yes you can. Brightness of LED panels is measured in Nits. A single Nit emits over three times more light than a single lumen. LED panels can be scheduled to change the brightness at different times of day.
Q: As the LED display is made of lots of tiles, there must be more flexibility in size and aspect ratio. Right?
A: Size and aspect ratio is a little bit more complex for LED displays than projection. Due to their modular setup, there is no limit to the overall image size for LED displays. True. But this is where it can be more complicated than projection. When looking at the size and aspect ratio, you also need to consider your content and desired resolution.
The LED panels that make up an LED display are a certain aspect ratio. If the same number of LED panels are used horizontally and vertically – it will retain that same aspect ratio. For example, Optoma LED panels are 16:9 aspect ratio. A display of 10x10 panels would keep the aspect ratio the same. But if the customer wanted a specific width and height, the aspect ratio may not be 16:9 and it would alter the resolution – as there would be more or less pixels depending on the size chosen.
Resolution is determined by the size and the pixel pitch of the LED display – that is, the distance between each LED diode/pixel in the panel. The narrower the pixel pitch, the greater the resolution of this panel.
Pixel matching the content to the native display resolution is always the best option. But if the content resolution varies or cannot be known up front, Optoma has a range of image scalers which use the exceptional HQView technology to give the best on-screen results.
So, if people want a definite size, they may need to compromise on the resolution and aspect and/or create content at that resolution. Optoma has simplified this for customers by offering a range of panels at specific sizes and resolutions.
Screen size (dimensions)
4 x 2.2m (180”)
5 x 2.8m (226)”
8 x 4.5m (361”)
10 x 5.6m (452”)
Customers can have custom sizes with different resolutions but they should try to ensure the overall display’s aspect ratio is consistent with its individual panels to ensure the image is not distorted.
Q: Why is it important to know where will the audience be?
A: The closer the audience is to the screen, the narrower the pixel pitch you need for them not to see individual pixels. As a rule of thumb – for a 2.6 pixel pitch, the minimum viewing distance is 2.6m away, for a 2.0 pixel pitch it is 2m. But this is not the optimal viewing distance. We advise that the optimum distance if roughly the width of the display. So the best place to view a 5m wide display is 5m back.
One more thing. You also need to think about the viewing angle. Better quality LEDs have a wider viewing angle. If your audience will be viewing the display far off-centre, you need to make sure the diodes have a wide viewing angle, which ours do.
Q: How accessible will the display be after install?
A: Some LED displays are only accessible from the rear which would need substantial framework, designed and signed-off by structural engineers.
All of Optoma’s out of the box solutions are designed to be mounted directly onto the wall using wood screws and are front serviceable with no cabling required to connect each tile. This makes installation and servicing quick and efficient. They also have 3-axis adjustments to mitigate uneven walls.
If one panel gets damaged, it can be simply swapped out without having to dismantle the entire display. It is easier and cheaper to change this single panel within an LED display than for a LFD or videowall.
Every display comes with a custom tool kit with everything needed to install, as well as spare LED panels and components. This includes a unique suction device for removing individual panels which significantly reduces the potential for damage during installation and servicing.
Q: Does it need much servicing then?
A: No. Optoma LED displays need minimal maintenance. There are no filters to clean. Fluctuations in temperature and damp may reduce the lifespan of diodes so we advise to leave the display on standby to keep these warm and dry. If there is a build-up of dust on the front of the display, you can brush this gently with a soft brush - but other than that, they need very little maintenance.
Q: What are the main pitfalls for installers?
A: One of the common pitfalls is that buyers look for the cheapest option and buy directly from a far East supplier. This is high risk as these companies request payment up front and, when there are problems, provide no local support. I would recommend choosing a trusted and established AV brand within Europe with whom they can be assured they would have support during and post install.
We can guarantee a single bin pick for LEDs. This means that the LED panels all come from the same production run to ensure a consistency in colour performance and brightness across the whole display.
Q: Anything else?
A: Once the size and resolution is set, this will determine what controller you would need. All Optoma displays come with a controller and all cabling.
Each controller has a fixed number of outputs to prevent bandwidth issues. Optoma MCTRL660 is designed for screens with a maximum resolution of 1080p. It has four outputs dividing a 1080p screen into four signal runs. A 4K resolution display would need a controller with 16 outputs – four times that of 1080p – so would use Optoma CTRL4K. If you need full redundancy, you would need an extra controller and cabling.
The only other thing to consider is the power needed for the display. This is dependent on size and brightness. We advise customers on the maximum consumption based on maximum brightness so they can arrange for the electrics to accommodate this.
Optoma has a range of ultra-thin, 16:9 native aspect ratio LED displays. These are easy to install, operate and maintain, and engineered for reliability and superior image quality.
Why choose Optoma LED displays
- Local stock, local support & cost effective
- High brightness, high-resolution indoor Full HD and UHD 4K LED displays
- Easy installation and maintenance – surface mount and front access
- Ultra-thin 56mm panel depth - discreet, space-saving design
- Best-in-class processing and switching – HQUltra technology
- Ultimate reliability
With an ultra-thin panel depth of only 56mm, Optoma LED displays are designed to take up less space, blending discreetly into any environment.
Easy installation and maintenance
They can be mounted directly onto a suitable wall using wood or plaster screws without a mounting frame. A simple, lightweight frame option is also available. Front access gives fast, low-cost installation and easy maintenance.
Designed, supplied and supported as a single solution, Optoma LED displays include everything you need – from cables to preconfigured processors for a hassle-free installation.
Scaling and switching
They use industry leading HQUltra 4K image processing technology for best in class picture quality and low latency video processing. Inputs can be switched seamlessly in as little as 0.25 seconds.