Large Venue Displays-Which to Use
Large Venue Displays-Which to Use
By Alan C. Brawn CTS, ISF-C, DSCE, DSDE, DSNE, DCME, DSSP
At the outset I want to comment on the process of doing display comparisons. Keep in mind the need to maintain objectivity throughout the comparison process. A true comparison is not meant to promote or discourage one kind of display technology over another. The goal here is to present the verifiable advantages and potential downsides of each type of display technology used in large venue projects. Think of features versus benefits versus potential challenges. No matter what you hear, one size, brand, type, etc. does not fit all. The project, the environment (and yes, the budget) will dictate to an AV designer or integrator what to use. No matter the choice, there will be tradeoffs… the secret is in knowing how to mitigate those. Next, put all the marking hype aside. Everyone will claim they are better in one way or another, and they may (or may not) be right. It is up to the digital signage system/network design professional to explore the unvarnished (marketing free) facts and see for themselves if a vendor’s claim is valid or relevant, and if a technology (and product) fits their application. There is no substitute for experience, knowledge, proper evaluation, and judgment.
Before I tackle the advantages and potential challenges for each technology, I want to address the opportunities and growth that these applications provide for our commercial digital signage design and integration community. I told you to downplay the marketing hype from various vendors, but I did not say to ignore the market. You will be pleased that there is not a “good news/bad news” story here, only good news. I mean really good news for those willing to grab the brass ring! According to reliable market research, the commercial digital signage market overall is growing at just under 10% per year. That may not seem significant to some, but keep in mind the US economy is growing at just approximately 3% per year. That is good news… but I promised you more. The large venue market, and especially both videowalls and outdoor displays, are growing at over 20% per year… and some niches at over 30%. That is what I call really good news. So now to the options.
Our objective is to make it clear to you what the most notable advantages and potential disadvantages or challenges are without getting lost in granularity and going off on marketing tangents. We will begin by describing each technology type, and then provide bullet points that will define elements that may take further investigation on the part of the digital signage designer.
When we think about large venue design options, projection is still at the head of the class. It is the only display technology that provides a nearly unlimited number of screen size options. Other than the behemoths of light output, most projectors can be moved around easily, positioned on a table, mounted in the ceiling, or used for front screen or rear screen applications. Projection can be edge blended for seamless ultra-wide or tall images and with pixel mapping it can make a building or space take on a new and expanded dimension to wow the viewers. The “bad guy” here is ambient light… but that may or may not be an issue.
- Projection advantages
- Low cost per square foot of image
- Portability (in some cases) of display
- Variable image sizes based on lens options
- Brightness and light source options to fit many applications
- Edge blending & pixel mapping
- Numbers of types of screen surface (to fit many applications)
- Projection disadvantages
- Impact of ambient light and image visibility
- Maintaining color and contrast of the source material
- 2-piece display technology – a more complex design due to positioning of the projector relative to the screen.
Large Flat Panel Displays (LFD):
By far the most popular display technology in general use today is large flat panel displays. Commercial models come in sizes from 32” to approximately 100”. They are a single piece solution… hang it on the wall or suspend it from the ceiling. They are sufficiently bright in standard form and high brightness models are out there. They are not as susceptible to ambient light when compared with projection. They are also high resolution with 8K UHD models beginning to be released. Can we all say image detail? They certainly provide good color and contrast performance. For large venue applications, flat panels will be commonly used to construct larger sized videowalls. Most commercial displays have a basic videowall processor built-in, and outboard processors with more capabilities are readily available. The major disadvantages to LFD are the bezels. Although new models are now available with a minimal bezel width compared to a few years ago, the bezels are still noticeable, and the cost of the narrow bezel models is higher.
- LFD advantages
- 1-piece approach – simple design, but requires precise installation
- Potential higher aggregate resolution (1080P or more per panel)
- Low maintenance – no light source to change or screen surface to maintain
- LFD disadvantages
- Cost – potentially higher per square foot
- Bezels – breaking up the image with black lines
- Glare – even matte screen surface models are susceptible to glare to a certain degree
- Off axis viewing – LCD displays may experience color shift or brightness fall off as viewing angles increase
- Complexity of setup (processing) – more devices involved to create the final product
Direct view LED (dvLED):
Although outdoor dvLED has been around since the mid-1990s, it is now the most heavily promoted large venue display technology today. This is due in part to the introduction of indoor fine pixel pitch products… but also due to a change in business models from manufacturers direct to end users to manufacturers to integrators where the commercial AV community can now sell dvLED to their clients. The benefits here are obvious. Direct view LED is bright and colorful with high contrast and depending upon the brightness of the model, it can be unaffected by high ambient light. Of course, it is seamless! The biggest obstacle remains cost versus other large venue options.
- dvLED advantages
- Zero bezels – truly seamless display
- Brightness and glare resistance
- Color and contrast are easily maintained
- Viewing angle – image remains uniform at nearly all angles
- Image size
- Low maintenance
- dvLED disadvantages
- Cost – higher/highest per square foot
- Resolution may be limited by pixel pitch and screen size
- Complexity of setup (installation) requires careful handling and precise installation
Ultimately, our job was to point out the advantages and potential downsides of each technology in comparison to one another. What you select is up to you… it is your experience, and your project. Our point is for you (along with our help) to educate yourself and be sure to look before you leap. If you have a truly high ambient light situation then projection is probably not the right choice… but if you are indoors with lighting control and need a huge ultra-wide or ultra-tall image, this may be the best bet. If you love the look of a videowall and want to show the image details in high resolution, then LFD should be your consideration. If ultra-bright and seamless is a requirement the dvLED appears to be the way to go. In all cases, budget will come into play. As we said in the beginning, it is a balancing act of features, benefits, and disadvantages. It takes you the digital signage design professional to navigate this course.