Layer Stack

Layer Stack is use to create image with combination of Red, Green, Blue and Near IR  images. 

Step 1,

Open ERDAS -- Spectral -- Layer Stack 

Step 2,

Select Images

Step 3,

then "Add" all four images one by one in order of Red, Green, Blue, Near IR

Step 4, 

Then press "ok" to start the process..

Step 5,

Then add your Image, then go to Raster -- Multispectral -- and change color combination in to red (3) - green (2) - blue (1)

red: 0.61 - 0.69 µm

green: 0.51 - 0.60 µm

blue: 0.45 - 0.51 µm

This band combination is used to represent an image in natural colour and therefore best approaches the appearance of the landscape in reality.

Step 6,

change color combination in to (Red) (4) - red (3) - green (2)

VNIR: 0.76 - 0.90 µm

red: 0.61 - 0.69 µm

green: 0.51 - 0.60 µm 

These three bands are typically combined to make a 'traditional' false colour composite as one also knows from aerial photography.