Most of the innovations on Bond Lane were either afterthoughts or solutions to problems that emerged along the way, but using a TV to create a digital and dynamic backscene was the reason for creating the layout in the first place.
In theory, it seemed straightforward: put a screen at the back of the layout and play a video of a cloudy sky. In reality, having such a strong light source behind the layout meant everything in front of it turned into a silhouette.
If all you wanted was a relatively consistent video playing on the backscene — such as a cloudy sky or a city skyline — then simply adding some additional lighting above the layout would easily solve the problem. However, our early experiments involved playing a few sample videos, including a sunset and a lightning storm, and the idea of incorporating both of these soon fixed itself firmly in our minds.
The first idea we tried worked well and remains part of the final layout. It was simple yet surprisingly effective. We took a light sensor from an electronics kit and hid it behind the viaduct next to the TV screen. We then wired this up to some LED strip lighting along with a power source. In this setup, the light sensor acted as a dimmer switch — when the TV screen was bright, the LED strip lights brightened; when the screen darkened, the lights dimmed too.
Even now it’s not perfect. The lights never go out completely, and I suspect that experimenting with sensors with different thresholds could cut the light entirely without reducing the maximum brightness. But we’re happy enough with the results, especially when combined with some of the other techniques we later added (more on those in the next blog post).
So effective is this approach that the LED lights can synchronise so precisely with the video that they flash perfectly in time with the lightning strikes on the backscreen.
As a technique, this was a significant breakthrough. It allowed us to develop additional methods to control how different elements of the layout responded to the video on the backscene — all relatively easily.
It’s also an inexpensive and accessible method that doesn’t require an advanced understanding of electronics.
In the next blog post, we’ll look at how we developed another technique that gave us control not only over the brightness of the layout, but also over the colour, to help really sell a sunset or other dramatic scenes.
