The 1990s saw the move toward widescreen (16:9) television.
The new aspect ratio required a new test card. Various modified forms of test card
'F' were used but the 1984 version was really due for an overhaul. Test card 'W' was
the end result. This card has even more exciting engineering twiddly bits
We now get luminance and chrominance sawteeth at the bottom of the frame, pure
colour difference castellations on the left of frame, extra framing arrows which
correspond to active picture if the image has been aspect ratio converted to
either 14:9 or 4:3. The bottom frequency grating is now 6MHz (this image is not
intended for analogue broadcast
) and the green blob in the letterbox is
designed to highlight luminance to chrominance delays. The spots in the greyscale
flash on and off this indicates that the video feed is 'live' and not an
image that has been grabbed in a framestore/VT machine
The highlight of this card is however, the central image. Newly scanned from the
original glass plate slide, Carol Hersee is looking even better than ever.
We now get to see more of the picture, the clown does have a piece of chalk! It
all makes sense now! The central cross on the blackboard really is in the centre
of the picture.