Image Correlation to quantify crack growth

Hi all,
I have been using ImageJ for analysis of Cracking in drying materials 
(soil). I am trying to quantify the crack growth taking one image (un 
cracked) with a image sequence (several images taken at different stages of 
crack growth).
I tried to use the plugins to correlate, but they can do with staks or 
images of equal number. Now, is there is any other plugin or method where 
in i can fix one image as the reference and correlate the rest of the 
images sequencially.

thank you all in advance.

Lakshmikantha, M.R.
Doctoral Student.
Dept. of Geotechnical and Geosciences.
ETSECCPB-UPC.
Barcelona.