Copying a Photoshop technique may infringe copyright.
Summary:
An English tea company used this image of a red London bus driving across a grey-scaled Westminster Bridge. It was almost identical to a photo by a souvenir company. The infringing image was withdrawn after a court dispute, but the tea company later produced new images they believed were less similar. The souvenir company disagreed…
Outcome:
A UK judge held that the new images were an infringement of copyright. Specifically, the tea company had reproduced a combination of “visual contrast features” in the scene.
The judge’s logic: using colour in a black-and-white photo (ala Schindler’s List) isn’t copyrightable, and neither is combining iconic images like a double-decker bus and the Houses of Parliament. But when you put both together, it’s a new “intellectual creation”. Thus, it was the expression of the skill and labour expressed by the photographer that was protected.
The idea/expression dichotomy is one of the trickiest notions in copyright cases, and this “Red Bus” ruling remains controversial in legal circles. It’s important to note that the infringer definitely knew about the claimant’s image before making his own, as he’d lost an earlier action in court involving the same image.