A sporting change
To coincide with the start of the 2007-8 football season and their new three-year deal with the Barclays Premier League, the BBC has commissioned a complete new look for its sports studio (Studio Five) at BBC Television Centre.
Programmes such as Match of the Day, Match of the Day 2, Football Focus, Score, Inside Sport and recently the World Athletic Championships in Osaka are produced from this studio.
The centrepiece of the new environment is a giant, 22-metre-long curved projection screen, the continuous image created from a seven-projector blend.
The seven networked Christie DS+8’s, fitted with 0.67:1 HD fixed lens and Twist modules, have been selected to create the perfect projection backdrop.
The background composition is provided by a three-output HD-SDI feed from the Grass Valley K2 1080i client media servers. These are controlled by a Vista Systems Spyder using the Vista Sourcemaster control unit. The signals are then sent to the projectors via a 50-metre DVI-D fibre source feed from a 10in/10out Spyder system in the first floor control room, with DVI – fibre conversion provided by Gefen.
The Corporation purchased the new technology from their regular suppliers, Magic Visual Displays, who also assisted the broadcaster’s engineering team with the installation.
The technological solution was conceived jointly by BBC Studios’ technical development manager, Danny Popkin, and BBC Resources Manager, Jon Sweeney, with the possibility of image warping and blending leading the BBC into new territory.
What the technical team sought to achieve was good resolution with a high degree of image controllability. The production team also wanted to benefit from the camera’s depth of field on developing camera shots — which meant that image resolution was not the ultimate driver.
The next challenge was the choice of projector and the broadcaster opted for a Christie 3-chip DLP SXGA+ solution following the successful deployment of Christie projection on its General Election coverage. The selection was based on this, and the fact that the integrated Twist modules obviated the need for expensive and space-consuming outboard units. Remote control of all parameters, including power up and down via Ethernet, was an added benefit.
Finally, the physical positioning of the projectors was critical, with 256-pixel overlaps between each of the seven projectors, giving an overall screen resolution of 8264 x 1050 pixels.
BBC Sport’s Head of Presentation Simon Buglione commissioned experienced TV set designer Chris Webster to create the environment; and while the 22-metre arc wraps around half of the circular studio, a series of perspex shelves, using around 50 DMX channels of Pixelite RopeLED (some 90,000 tiny lamps) form a similar arc, which folds into it. Within this periphery the designer placed the rostra and presenters table.
In June this year, TV set construction specialists, Scenex, moved in to build the pre-constructed set, including the painted plywood projection screen and a floor-standing unit with portholes which both houses the projectors and acts as a sound baffle for the projector fans.
Finding the right pixel processor
Back in January Jon Sweeney attended the ISE Show in Amsterdam with David Lindsay of Magic Visual Displays, where both Christie and Vista Systems (a Christie company) were exhibiting. Having reviewed alternative pixel processors they selected the Vista Spyder.
Features such as cropping, cloning and linear keying — which are used extensively for logos and animated graphics – were demonstrated as part of the product’s functionality. The ShotBox controller, already used extensively in broadcast, was also a key feature that allows multiple layers to be controlled as a single object.
The Vista Spyder also met the requirement to manipulate the size of graphics, position them and mix on and off screen at the push of a button.
Another important factor was that Spyder had already been in the field for several years, and finally, with many operators working across several different programmes, the relative intuitiveness of the system was a further consideration.
At the Corporation, an operator’s monitor offers programme and preview from Spyder with overall control using a KVM and a DNF ST420-VSS ShotBox. Spyder takes in three moving background images from a K2 media server, which are run synchronously via the Vista Systems Sourcemaster; this is a specific IP address to the RS232/RS455 interface box, which can control up to four players/servers simultaneously. Spyder launches the playback on the servers when the operator recalls a preset.
With fill and key from an HD Vizrt (a real-time 3D character generator — used for spinning and enlarging the interlude ball), and the five remaining inputs from the studio’s main video matrix the set-up offers the ability to place virtually any video source onto the wall.
All colour rendering and colour grading is the responsibility of the graphics operator and entails processing a combination of photos with 3D models in Maya and After Effects software packages.
The BBC’s choice of equipment was to prove significant, as subsequent to the selection and procurement process, the merger of complementary technologies was completed with the corporate takeover of Vista Systems by Christie.