
The Atmosphere plugin for After Effects realistically simulates atmospheric conditions such as haze and fog in your composition.
Layers further away from the camera appear to be more deeply immersed in the haze/fog than layers closer to the camera. This also applies to parts of layers: If one edge or area of a layer is closer to the camera, this area will appear less immersed in the haze/fog than the pixels further away. You can simulate very realistic or very unrealistic types of atmospheric effects using the Atmosphere plugin.
The strength of the atmosphere plug-in doesn’t shine in a single-layer comp. Much like our falloff lighting plug, you get the full benefit when working in after effect’s 3D mode and have multiple layers with different Z-depths, atmosphere will apply the fog effect differently depending on lighting and distance to the camera.
Display Corner Depths
Displays the distance from the camera to the corners of the layers. This can be used to figure out what value should be entered in the Start and End Depth parameters.
For example, if you want the corner closest to the camera to be unaffected by haze or fog and the value in this corner reads “1500”, entering “1500” in the Start Depth parameter will keep that corner clearly visible 100%.
Color
This changes the color of the fog. In the real world, a haze is almost transparent white, while fog tends to be white or light gray, so the default setting is white. Smog and other types of atmospheric junk can cause other colors to appear, such as oranges and reds.
Start Depth
This sets the distance (in pixels) from the camera where the fog begins. Pixels closer than this distance remain unchanged. Pixels at or beyond this distance have some amount of fog applied to them.
End Depth
If you set the Rolloff parameter (described below) to “Linear,” then the End Depth is the distance from the camera where the fog becomes opaque. Anything at or beyond this point is completely covered by the fog and cannot be seen.
Pixels between the Start Depth and End Depth have proportionally more fog as their distance from the camera approaches the End Depth. If you set the Rolloff parameter to either “Exponential” or “Exponential Squared,” then any pixels beyond this distance from the camera have the same amount of fog as pixels at this distance.
Rolloff
There are 3 different types of fog you can apply:
1 Linear: The amount of fog that covers a pixel is directly proportional to the distance of that pixel from the camera.
2 Exponential: The amount of fog that covers a pixel varies not only with the distance of the pixel from the camera, but also with the value of the “Density” parameter.
Exponential Squared: This works in the same manner as the Exponential version, but increases more slowly at near distances and more quickly at farther distances. See Figure 1.0
3 Density: This parameter is only valid if the Rolloff parameter is set to “Exponential” or “Exponential Squared.” It determines the rate at which the fog increases as the distance from the camera increases. Larger values will increase the fog’s opacity more quickly as you move away from the camera.
Input Gamma
This parameter is only available on the individual layers’ effect and won’t display on the Master Fog
Control Layer’s list of parameters. This should be set to the gamma of your video footage. If you’re using
video in a broadcast format, such as DV, MPEG, MJPEG, etc. it should be set to 2.2.
If your footage is compressed with Apple’s “Animation” codec for QuickTime, it should be set to 1.8
(even on Windows). If your footage is from a 3D application that does not apply gamma correction, it
should be set to 1.0. If you’re unsure of the value, 2.2 is a safe setting to use.
Setting this value correctly will make the fog look more realistic.
Downloadable PDF :
Atmosphere Manual
After Effects 7, CS3 and CS4.
Mac
OS X 10.4+
G4/G5/Mac Intel Processors
Minimum of 1 GB system memory
PC
XP Professional SP2/Windows Vista
Intel Pentium 4 or AMD Athlon XP
Minimum of 1 GB system memory