LED Vs Projection
Why should you chose a LED video screen over a projection screen for your outdoor cinema event?
To start this somewhat 'techy' subject we need to understand what a LED video screen is and how it differs from video projection.
Image (above) illustrating projection on inflatable screen (Altered by Photoshop)
Video projectors are the most common method for outdoor cinemas and are usually paired with a inflatable screen. As the name suggests the image (film) is 'projected' onto the inflatable screen surface from the projector. The light (image) is reflected back off the the white screen surface which is how we see the image.
LED video screens are very different to projectors as they do not require the light to be reflected back into our eyes but emit the light directly from the screen (similar to your TV in your home). Light is emitted directly from thousands of individual LED lights (light-emitting diodes) which make up the LED video screen. When all these individual LED lights work in harmony and change colours thousands of times per seconds they create the image we see on-screen.
From the above you can see how LED screens and Projection screens work very differently. Until recent years they both had their own advantages and disadvantages, however with the development in LED video screen technology LED has now become the preferred choice for many AV professionals.
The most obvious and key difference between projection and LED for outdoor cinema is brightness. LED wins hands down with this one and the image below helps demonstrate this.
Image (above) shows Shine Cinema LED screen (Left) compared to competitors Projection (Right)
Unfortunately the measurement of brightness of a LED screens (refereed to as Nits) can not be directly compared to the measurement of brightness of a video projector (refereed to as Lumens) however a good comparison can be made between your standard home TV designed to be viewed indoors much like a projector, which has a brightness of around 300-600 nits compared to a LED video screen with a brightness of 5000 nits. LED SCREENS ARE BRIGHT! This allows them to be used outdoor in sunlight making them ideal for family friendly cinema screenings during the day.
Projectors on the other hand are not suitable for daytime use and may struggle to provide a view-able image even in a dark sheltered corner out of direct day light.
Most projection based outdoor cinema providers suggest starting your film after dusk (Twilight) to allow the ambient light to be low enough to allow the projected image to be seen. In the UK summer months this can be as late as 9:30pm!
A added bonus of LED video screens is the brightness can easily be adjusted allowing them to be used after dusk as well as during the day without being too bright and blinding the audience. Our LED screens typically run at 15% brightness once it is dark.
Until recently this is where projectors had the advantage over LED video screens.
We are all aware of the terms HD and the ever increasing array of resolution such as 4k and Super HD. Projectors tend to be fairly up to speed with these trends as they share many components with your standard home TV.
LED screens have struggled in the past with resolution as each pixel which makes up the image is made of a individual LED light. To create a HD image 100,000's of these LED lights are required to produce the resolution, however it had not been possible to pack all these LED lights in such a small surface area of the screen, limiting the overall resolution of the LED video screen.
A new wave of LED video screens using SMD leds have changed this allowing much higher resolution screens. LED video screens can now achieve full HD resolution, and beyond.
This does bring up the debate weather you actually need such hi-resolutions for outdoor cinemas where your audience are sat further away from the screen than you ordinarily would within your own home? and if they benefit from it?
Resolution is certainly important however a hi-resolution screen is never going to compensate for a low-brightness or poor quality cinema screen.
Shine Cinema use some of the highest resolution outdoor LED video screens in the UK, capable of providing HD (Hi-Definition) resolutions.
Other key factors
Although brightness and resolution are the key factors you also need to consider technical specs such as grey scale (the contrast between the brightest and darkest part of the image possible) and re-fresh rates (how fast the image is refreshed between frames).
Overall the latest LED video screens win on both these fronts and the white surface of a inflatable screen provides very poor grey scale unless it is completely pitch dark. With light pollution from nearby street lights and even the moon this is rarely possible.
Re-fresh rates is yet more technical, but the higher the number quoted the faster the image is refreshed and the stabler the image will appear to the viewer. LED video screens vary greatly on this, however our LED video screens at Shine Cinema run at 3820hz compared to 120 to 500hz of video projector, This means LED screen provide a much more stable and flicker free image than projectors.
Now that we have jumbled your brain with all this tech talk its about time we took a break.
Hopefully you now understand a little more about LED video screen Vs Projectors and why we chose LED over Projection at Shine Cinema.
Be rest assured we use the latest LED video screens at Shine Cinema providing the best possible 'Outdoor Cinema' experience.