Test Card J is a test card, an image used to determine the quality of a broadcast television picture. It is an updated version of Test Card F, which was created by BBC engineer George Hersee.
Differences
The centre picture in Test Card J is a re-touched version of the picture at the centre of Test Card F, to make the colours in the image look more accurate. The centre picture was also re-aligned within Test Card J to put the cross on the noughts and crosses board at the exact centre of the screen.
A green square at the top of the screen, which does not appear in Test Card F, is used within Test Card J to facilitate an easier observation of chrominance to luminance delay.
The color bars at the top of the card are increased from 95% intensity to 100% intensity from Test Card F to Test Card J.
See also
Images of test cards