yeah
i got your problemmm.
on the chirp dual port optical time domain visualizer, you are clearly able to see the the small blue box on the top left side of the image …
you click on that a no. of options will appear.. select the option you may need.. loooks like that zoom option will work for you… you may also need pan option for proper position of chirp position on the time scale basis.
you can also export bMP file (image) of that zoom part for analysis.
with regards