What is gamma?
Gamma is a number that describes how bright or dark a screen shows colors. It tells the computer how to turn the digital values (like 0‑255) into the actual light you see, making images look natural to our eyes.
Let's break it down
- Digital images store colors as numbers.
- Our eyes don’t see light linearly; they are more sensitive to dark tones.
- Gamma adjusts the curve between the stored number and the light output, usually using a value around 2.2 for most monitors.
- A low gamma (e.g., 1.0) makes the picture look too flat, while a high gamma (e.g., 3.0) makes it look too contrasty.
Why does it matter?
If gamma isn’t set correctly, pictures can look washed‑out or overly dark, and details in shadows or highlights may disappear. Proper gamma ensures that what you see on the screen matches the creator’s intent and looks consistent across different devices.
Where is it used?
- Computer monitors, TVs, and smartphone screens.
- Photo‑editing software (Photoshop, GIMP) when you adjust “Gamma” or “Exposure.”
- Video games and graphics engines to calibrate rendering pipelines.
- Web design, where CSS can specify gamma‑corrected images.
Good things about it
- Makes images look more realistic to human eyes.
- Allows designers to control contrast without changing the actual pixel data.
- Standard gamma values (like 2.2) create consistency across many devices, simplifying content creation.
Not-so-good things
- Different devices may use slightly different gamma curves, leading to mismatched colors.
- Incorrect gamma settings can hide details or cause eye strain.
- Some older hardware or software may not support proper gamma correction, resulting in poor image quality.