Test Cards these days are not suitable for the digital age
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After seeing the channel 4 testcard I have realised that the current crop of test cards not suitable for digital television they need to have movement in them in order for the effect to be seen on the other channels on the mux and weather the image quality is appropriate for their own channel with something like flowing water and various forms of natural light in it to see if the image quality is appropriate
They should also frequently change the resoloution and the aspect ratio during the testing process to simulate a variety of prints
There should be two different sounds for each speaker and if supported dolby digital sound tests as well
They should also frequently change the resoloution and the aspect ratio during the testing process to simulate a variety of prints
There should be two different sounds for each speaker and if supported dolby digital sound tests as well
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But I agree, since I have had my 16:9 (100hz) TV I have noticed many situations where the settings need to be tweeked.
Noticeably (sp?) when credits are rolling along the bottom of the screen at a fast speed. These are usually unreadable and require adjustment do the "digital scan setting".
When I get round to it I try to record such images so that I can go through the many setting variations on my TV to get the best possible picture.
But as you say an animated test card would be most helpfull, but when / where could they show it?
I was talking more about testing the launch of new DTT channels so the image quality is significantly viewable and that could only be done with an animated testcard
Yet but a an animated testcard would allow the enginneers at NTL/Crown Castle to configure the channel more accuratly
With the signal quality level shown with most digital boxes this is probably seen as not so neccesary.
With digital the picture is either there - blocked (breaking up or not there at all.
But asa I said I miss any sort of Test Card on the British system, although as you say, variations are needed and animation would help.
The set is "inventing" an extra field to fill in between each pair of real 50Hz fields transmitted. It is annoying, but I'd rather have that annoy me once in a while rather than flicker annoying me all the time ...
That depends entirely on what is being tested. The traditional testcard (and the one some people here believe is the only one you can call a testcard - I would disagree personally) is used for setting up the TV to correctly display a picture, as can be used for testing the feed from a broadcaster. This is usually accompanied by uadio, which I believe is an alternating left/stereo test tone.
The testcard currently being displayed on More4 is more for (no pun intended) testing the feed from the broadcaster, ensuring there is video and audio and in colour. You may have noticed it also identifies the source, which can be helpful for regionalisation issues.
A lot of DTT channels seem to be tested merely by displaying a blank screen (the original Freeview tests had a black screen with the feed ID on it), and then connecting up to an advertising loop or slide some come straight online with an already-broadcasting channel.
The BBC have a specially produced piece of film used for testing digital output, which contains fast fades, running water and other things that digital can have problems with. This is the semi-famous windmills test loop that was last seen when 701 and 702 started up on mux A. Given that the BBC intended to use these streams for sport, this loop was presumably used to check the quality would be acceptable for such a high bandwidth application.
Chris
These days, it's Test Card J and W. They're modern versions of F in 4:3 and 16:9 respectively.
As for a moving test card for the digital age, one exists. It's called Test Card M.
http://www.sptv.demon.co.uk/testcrdm.htm (look at 3rd link from bottom - seems to be the best one)
It's filmed mostly in the South West of England, and is an interesting piece of film in it's own right. It also uses various tracks from Aphex Twin as its soundtrack.
I have a copy on VHS somewhere in the houe.
We saw it during the 16QAM and 8K tests too, which I think was slightly more recent.
Its only so C4 get noticed that they have another channel launching soon - or hold one on the digital platform.