microtubule length

[Francine Perrine-Walker]

Dear All,
Sorry I am new to the Image J scene. I was wondering what the best way to
use imageJ to measure the length of microtubules (GFP labeled tubulin).
There is the simple line function but I heard there is a tracking
function. I wondered if anyone could tell me some of approaches they have
used to tackle this problem.
Regards
Francine