Open up shadows or deepen midtones without clipping black or white. Gamma from 0.1 to 3.0 with a live preview, in the browser.
Bends the tone curve in the middle while pinning both ends. Black stays black and white stays white no matter what you set; only the values between move. A gamma above 1 lifts midtones and shadows, so a value of 64 becomes about 105 at gamma 1.4 while 255 stays 255. Below 1 it does the opposite and deepens midtones. Because nothing ever clips, this is the safest way to make a dark photo readable, and it is the same correction a display uses to translate linear light to what you see.
A photo of a cave interior lit by a single lamp: the walls sit at values of 25 to 60 and read as black on a phone. Gamma 1.8 moves 25 to 70 and 60 to 114, so the rock texture becomes visible, while the lamp itself at 250 stays at 250 and does not blow out. Trying the same rescue with brightness at 200% would push the walls to 50 to 120 but also turn the lamp and everything near it into a white blob. Going the other way, a washed-out scan at gamma 0.7 gains depth in the text without the paper going grey.
Use it when the shadows and midtones need help but the highlights are already right: dark interiors, night shots, backlit subjects, images that look fine on a bright monitor and murky on a phone. It also suits the reverse case of a hazy, light image that needs its midtones brought down. It is not a brightness control for pictures that are uniformly dark; there Change Exposure is quicker and more natural. And it does not add contrast; combine it with Change Contrast if the result looks flat.
Gamma runs from 0.1 to 3.0 with 1.0 meaning no change. Values from 1.2 to 1.8 are the everyday range for lifting shadows; 2.2 mirrors the standard display curve and is a useful test value; below 0.8 things get dramatic. The chips jump to those points. The curve is applied through a 256-entry lookup table, so a 20-megapixel image finishes in well under a second. Output format and quality are in the Output section, and Batch mode treats a whole folder the same way.
Is gamma the same as brightness? No. Brightness moves every tone, including white, and clips. Gamma leaves pure black and pure white exactly where they are and moves only the tones in between, so it never clips.
Which direction lifts the shadows? Values above 1. At gamma 1.5 a dark grey of 50 becomes about 86; at gamma 0.7 it drops to 25.
Why does the picture look flat after a big gamma? Lifting the shadows a lot compresses the range that was in the highlights, which reads as lower contrast. Follow up with a small Change Contrast, around 110 to 120 percent.
Are my images uploaded? No. The lookup table is built and applied in your browser; nothing leaves your device.