This flash workshop is the 3rd of 6 different others, presenting 6 different applications of the commercial 3D software Imaris, from visualization, to network description. The objective of this workshop is to briefly discuss the different approaches needed for 3D quantification. This workshop includes 6 sub-workshops dealing with the different 3D/4D visualization and quantification tools for image analysis and illustration. This flash tutorial deals with the notions of quantification at the cellular level at the three-dimensional scale. Thanks to the Drosophila model, the objective is to analyse the "object" aspect in 3D by recovering information on the number, the volume or the morphology. We will use a series of images on which the participants will be able to launch the whole process of segmentation in real time step by step by going straight to the point. At the end of the workshop, participants will be provided with a "check point" tool that will allow them to reproduce the analysis on their respective workstations with their own 3D image analysis solutions, commercial or open source.