Adding ten percent more light than metered — compensates for digital sensor underexposure and keeps skin tones saturated. Standing practice on digital sets.
On set, you quickly notice: the camera reads light differently than your eye. Digital sensors, in particular, tend to render the scene darker than it actually appears — not because something is wrong, but because most modern cameras expose conservatively to avoid clipping in the highlights. This is where Plus Ten comes in: a tried-and-tested rule of thumb that states you should bring ten percent more light intensity into the image than your exposure meter actually indicates.
In practice, this means specifically: if your light meter indicates f/5.6 for a particular scene, you actually set it to f/4.8 or increase the intensity accordingly. This additional light flow not only compensates for sensor underexposure — it also gives skin tones visibly more richness and depth. Especially with portraits and close-ups of the face, this makes the difference between flat and cinematic. The skin appears fuller, the eyes gain sparkle, without you slipping into overexposure.
The ten percent is not a law of nature, but a rule of thumb that has proven effective with most digital cameras — especially with RED, ARRI Alexa, and Sony Venice. Depending on the sensor characteristics and color science, the optimal value varies slightly. Some DoPs work with Plus Eight, others with Plus Twelve. The trick: you measure precisely, note the result, and then mentally or physically add your percentage points. This is not gambling — it's calculated optimization.
Consistency is most important. Plus Ten only works if you implement it systematically — from calibration to setup to editing. In grading, your colorist will immediately notice if you've exposed erratically. Conversely: a consistently Plus-Ten-exposed shooting day can be graded elegantly and precisely because the data sits within the optimal sensor window. No noise, no artifacts, full information in the midtones and shadows.