easy way - https://www.photrio.com/forum/thread...-effect.62519/. You could probably reach out to Andrew for his advice.

DIY Way
use a step wedge in front of your 4x5 film, Take several shots at different f-stops keeping time same, measure densities and see how far off a certain tone drifts. IF linear it will change 1 stop, but probably not and your plot will show it to you. You could also do it under an enlarger as a contact stepwedge to film print, raising the light and using neutral density filters for longer exposure times. Proccess all your film together so there is no variance in development.