A dimming curve defines how a fixture translates its intensity-control value into output. Common named options include linear, logarithmic, exponential and S-curve, though the exact response depends on the manufacturer.
Why curves change a fade
A curve can allocate more control travel to a particular part of the output range. This affects how a manual adjustment or programmed fade feels. A 50% control value does not universally produce half the measured illuminance, and half the illuminance is not the same as half the perceived brightness.
Practical example
Fade two fixtures together onto the same neutral surface. If one drops quickly while the other holds, check their dimming curves, minimum output and console processing. Match the intended response before adjusting fade timing to compensate.
Curve, smoothing and flicker
Dimming curve, response smoothing, bit depth and PWM frequency are separate controls or characteristics. Changing the curve does not by itself guarantee flicker-free camera operation. Test the intended low levels, frame rate and shutter setting, especially when the shot includes a visible fade.
Equipment examples
The Aputure LS 600x Pro and Aputure STORM 1000c provide selectable dimming responses. Match the selected curve when comparing fades.
Related terms
PWM (Pulse-Width Modulation) · Flicker · DMX Personality