Sectioning Bone and Second Moment of Inertia

Hi All!

I am just doing my thesis work but have run into a few speed bumps with using BoneJ plugin on Fiji. One of the things I would like to do is section my bone images into eight sections (I have included an example of this below). I cannot seem to figure out how to do this using imageJ. The second issue I had was in regards to the Imin and Imax lines on my images, they appear white and blend into my background (image attached). I want them to appear more prominent in the photo, is there a way to do this?

Thank you all!

Annotated_BN-12 image 3 x20.tif (1.8 MB)