OK shado changes are hard.
This is a problem when you have a shadow from a car on to a shadow catcher. And you want it to blend perfectly with the existent shadows from buildings and other objects.
So I masked the shadows. And rendered 2 different shadows with 2 different settings.
And then blended between them using the mask
( tho there was a lot of color and intesnity correction to do this.
Also I needed to color correct the backdrop part to fit the shadow color scheme
Since sun gives it a yellowinsh tone. Darkening the yellow will not do you the best shadow.
You can see there is a desaturation happening at the place where shado should be
THIS IS THE FINAL IMAGE… (before the grading in the VSE that adds to it an effect of 16 mm film )