Everything you need to know about Gamma
Gamma adjusts the brightness of midtones using a power curve, while keeping pure black and pure white unchanged. It's a fundamental tonal adjustment that affects how bright or dark the "middle" tones of your image appear, based on the same gamma correction used in displays and color management.
Parameters
- Gamma
Controls the midtone brightness curve. Values greater than 1.0 brighten midtones (making the image lighter overall). Values less than 1.0 darken midtones (making the image appear heavier). At 1.0, no change is applied.
How It Works
The filter applies the formula: output = input^(1/gamma). This creates a smooth, nonlinear curve that bends the tonal range. Black (0) and white (1) stay fixed at the ends, while everything in between shifts lighter or darker depending on the gamma value.
Common Values
- 0.5 – 0.8
Darkens midtones significantly, adding density and drama - 1.0
No change (linear) - 1.2 – 1.5
Lightens midtones, opens up shadows - 2.0 – 2.2
Standard display gamma compensation range
Tips
- Use gamma 1.1–1.3 to brighten a dark image without blowing out highlights
- Use gamma 0.7–0.9 to add richness and weight to a washed-out image
- Gamma affects midtones most – extremes stay anchored
- For finer control over shadows, midtones, and highlights separately, use Curves