diff --git a/zigrtiow/src/color.zig b/zigrtiow/src/color.zig
index 4adca61..ac98f3c 100644
--- a/zigrtiow/src/color.zig
+++ b/zigrtiow/src/color.zig
@@ -8,11 +8,11 @@ pub fn write_color(c: Color, samples_per_pixel: isize) anyerror!void {
     var g = c.y();
     var b = c.z();
 
-    // Divide the color by the number of samples.
-    var scale = 1.0 / @intToFloat(f32, samples_per_pixel);
-    r *= scale;
-    g *= scale;
-    b *= scale;
+    // Divide the color by the number of samples and gamma-correct for gamma=2.0.
+    const scale = 1.0 / @intToFloat(f32, samples_per_pixel);
+    r = @sqrt(scale * r);
+    g = @sqrt(scale * g);
+    b = @sqrt(scale * b);
 
     // Write the translated [0,255] value of each color component.
     var ir = @floatToInt(u8, 256 * clamp(r, 0, 0.999));