Editing Test Card F (section)

===Test Card J ===
{{anchor|testcardj}}
'''Test Card J''' is an updated version of Test Card F, and first appeared in November 1999. It includes the following changes relative to its predecessor:

* A newly added green square at the top of the screen is used to facilitate easier observation of chrominance to luminance delay.
* The negative black squares in the left hand step pattern should flash on and off at 1 [[hertz|Hz]]. This is to aid in the detection of frozen digital links.
* The central image is based on the same source photograph, but with some minor adjustments:
** It has been rescanned from the original transparency for improved colour accuracy.
** The image has been re-aligned within Test Card J such that the cross on the [[noughts and crosses]] board is at the exact centre of the screen, as some believe was originally intended.
** It is less tightly cropped, resulting in more edge detail from the original photograph being visible.<ref name='meldrum'/>