The curse of the tone mapping operators
Very smart algorithms are seductive, but the results can be juvenile
You might well ask in response to this title ‘What curse? Aren’t these tools such as highlight recovery, clarity and de-haze simply marvellous new ways, inconceivable in the days of film, of bringing out anything and everything from an image and enabling total creative freedom?’
These relatively new algorithms work at the level of neighbouring pixels in quite complex operations, and are all the children of HDR tone-mapping, hence the term tone mapping operators, or TMOs. They work locally but are normally used globally, although Adobe’s ACR (that is used by both Lightroom and Photoshop) enables you to apply them locally, as in a radial filter. The seeming miracle of opening up shadow areas, restoring detail in highlights and generally making everything look more detailed and clear has been widely embraced. So what’s to complain about?
There are two issues. One, which may sound churlish, is that they make images look less traditionally photographic, which we discussed in Treat it like a photo, opposite. It’s enough here to say that they all have one thing in common – they’re designed in one way or another to reveal more from the image. That seems to be hardly questioned nowadays, but many photographs in fact depend on not revealing all. You might call that the value of shadows.
The second is that there are no restraints on using them to extremes. They invite playing around and the results can be, frankly, childish. And yes, that’s just my opinion.
A spectacular cloudscape as a storm builds over the high grasslands of western Sichuan (above), with a highly over-processed version generated with TMOs in what has become known as HDR style (left). This kind of treatment is easy to overcook