HD Enhancement Curve

Operational Products Development Branch (NOAA/NESDIS)

The graph below shows how the gray scale intensities for the HD curve vary with input brightness temperature (deg C).

Here is a table showing output gray scale values versus input brightness ranges and Band 4 (10.7 m m) IR temperatures for the HD curve

Segment | Input | Temp Range | Gray levels | Feature
0 | 0-58 | +50 to +27.8K | 0 | No information
1 | 59 - 82 | +27.3 to 15.8 K | 0 - 50 | Land/water
2 | 83-114 | +15.3 to 0.3 K | 50-210 | Water and low clouds
3 | 115-119 | -0.2 to -2.7 K | 0 | Freezing zone
4 | 120-174 | -3.2 to -30.2 K | 100-255 | Mid-tropospheric fronts
5 | 174-186 | -30.7 to -41.2 K | 60 | Dark gray
6 | 187-198 | -42.2 to -53.2 K | 110 | Medium gray
7 | 199-208 | -54.2 to -63.2 K | 160 | Light gray
8 | 209-214 | -64.2 to -69.2 K | 0 | Black
9 | 215-220 | -70.2 to -75.2 K | 255 | White
10 | 221-225 | -76.2 to -80.2 K | 140 | Medium gray
11 | 226-231 | -81.2 to -86.2 K | 100 | Dark gray
12 | 232-255 | -87.2 to -110.2 K | 0 | Black