BBC test chart 57
BBC test chart 57, greyscale reflectance chart for colour television cameras, 1970.
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New test cards needed to be made for the introduction of colour television cameras. The cameras had better performance, so a new greyscale was needed to improve the contrast ratio, grey balance, and gamma correction of BBC colour television cameras. Having the black, white and grey levels correctly calibrated helped to create optimum colour fidelity, giving more accurate colour, in the transmission.
The square in the middle was to create ‘super black’ which had little or no reflectance. It was made by cutting an aperture into the card and fixing a small box lined with black flock paper behind it. This reduced the amount of light reflected, to help with camera flare correction adjustments.
- Measurements:
-
6 kg
- Materials:
- paper (fibre product) and printing ink
- Object Number:
- 2012-5118/771/1
- type:
- test chart
- Image ©
- The Board of Trustees of the Science Museum