Why does the picture quality on HDTV adverts look better than normal, despite being viewed on a non-HDTV?

22nd July 2009
Why does the picture quality on HDTV adverts look better than normal, despite being viewed on a non-HDTV? (Getty)

Asked by: FOCUS

Standard-definition TV lacks the sharpness and resolution of HD, so you wouldn’t expect high-def pictures to look any different on it. But if they are shot on HD the source material is higher quality this will be preserved through the editing process. Also adverts themselves tend to have higher technical production standards than normal programming, specifically so they do stand out and grab our attention. The main reason though is probably just an optical illusion. Most HD adverts show a subject in slow motion. If the slow motion footage is shot with very high depth of field and with a very large number of frames per second, the entire image will still appear sharp. This is just ‘normal’ sharpness but because the subject was moving quickly, it is something we would normally expect to appear blurred. In the slow-motion footage, it appears sharper than we think it should and so the picture seems better than normal.

 


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