Question 14

Raw files let you claw back lost highlight and shadow detail – but how much?

ANSWER (A) Score ½ (B) Score 1 Answer (B) is closest. Digital sensors are quite tolerant to underexposure, but much less tolerant to overexposure. You can often drag amazing amounts of detail out of apparently impenetrable shadows (even if this detail is noisier), but you have much less leeway with ‘blown’ highlights. This is most common with the dreaded ‘white-out’ of skies in outdoor shots. Your raw converter may be able to get back delicate details in bright clouds if they’re not too heavily overexposed, but about 1EV of correction is usually the limit. After that, you’re not getting more highlight detail: you’re changing it from a brilliant, featureless white to a muddy, featureless grey!

‘Blown’ highlights The sky is so bright that some of it has lost all detail. Digital cameras do lose highlight detail quite easily. Dense shadows The front of this building is in shadow. You can still see some detail, but it’s very dark, and the picture looks dull.

Highlight recovery With around 1EV of extra highlight detail, we’ve recovered detail in the clouds, but the sun is still blown out. Shadow recovery We can recover a lot more detail in the shadows, typically 3-4EV. Keep this in mind when setting the exposure.