Change spatial calibration

I would like to know if it is possible to change the spatial calibration of a volume in Slicer.
I import a tiff stack from a tomography reconstruction made with TomoJ (in ImageJ). I didn’t found the way to set the voxel size.
Thank you

This documentation section explains how you can import and calibrate an image stack:

Thank you, as I understand this step is at the importation of the tiff stack. But one the model is generated and saved into a VTK file is it still possible to change the spatial calibration?

Yes, you can use the Volume Information Panel to modify the image properties ( you just have to be careful when you do this as this will affect all your subsequent quantitative computations)

It doesn’t seems to work with a model.
When I open my VTK file, it is considered as a model and I don’t have the possibility to change the scale.

You can easily scale models using Surface Toolbox module.

If you want to transform volumes and images together then it is easier to use Transforms module: create transform, set scaling factors in the diagonal values in the transformation matrix, apply transform to all nodes (models, volumes, markups, segmentations, …), then harden transform on all nodes.