Grey Scale analysis for exfoliated MoS2 particle thickness

I am having difficulty figuring out how to use imagej in order to analyzed a grey scale image for particle thickness distribution. We are analyzing thin, few layered and monolayer MoS2 particles. Thickness has a direct correlation to the number of layer within the MoS2 particle.

Is there a way to analyze a microscope image of these exfoliated particles and create a distribution of thickness based on the greyscale values of the image?

Any help is greatly appreciated!!

It would help if you post an example image for the forum.

However have also a look at the 3d ImageJ Suite:

Another possible way might be to make a Z-project of a stack followed by a particle analysis, see: