diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
index 9a33094a..3d1b058f 100644
--- a/src/libcamera/control_ids.yaml
+++ b/src/libcamera/control_ids.yaml
@@ -192,13 +192,20 @@ controls:
 
   - Brightness:
       type: int32_t
-      description: Specify a fixed brightness parameter
+      description: |
+        Specify a fixed brightness parameter. Positive values (up to 65535)
+        produce brighter images; negative values (up to -65536) produce darker
+        images and 0 leaves pixels unchanged.
 
   - Contrast:
-      type: int32_t
-      description: Specify a fixed contrast parameter
+      type: float
+      description:  |
+        Specify a fixed contrast parameter. Normal contrast is given by the
+        value 1.0; larger values produce images with more contrast.
 
   - Saturation:
-      type: int32_t
-      description: Specify a fixed saturation parameter
+      type: float
+      description:  |
+        Specify a fixed saturation parameter. Normal saturation is given by
+        the value 1.0; larger values produce more saturated colours.
 ...