Hi Stephenie. In this case, the shadow is not going to be the shape of the car. In fact you don't need to be fussy about the shape of the shadow and can just paint it in with a brush. This is a car floating in the air.
All I did is use a medium size fully hard round brush, and stamp down under one of the wheels.
I then Shift clicked to the next wheel, and again to the third visible wheel.
I then filled in as much of it as would show, and made it a Smart Object.
I used a fairly high value Gaussian blur. Because it is a Smart Object, I can turn the blur off, or adjust its value as many time as I need. This is what it looks like with the blur turned off. You can see I was not over fussy.
It is usually necessary to use multiple shadow layers, because different areas will need different properties.
Notice that the wheels are still floating. So we need to tie them to the ground with a smaller, and much harder shadow.
I actually used separate layers for each wheel, because it was easier, and merged them. I don't need to make this layer a Smart Object, because I fine tune with the Smudge tool. Try it. Set the smudge tool opacity to 50%, and drag the shadows to fine tune their size and position. This is a useful trick in all sorts of situations.
What I like to do if I have time, is to leave the image for an hour or so, and come back to see if things like shadows still work.
One last thing. You didn't ask, but the car has windows. So I selected them with the Pen Tool, and used the work path to make a selection of the windows, and then add a layer mask to the car layer.
That makes the car disappear, so I inverted the mask (Ctrl i)
This leaves the windows full transparent, which would only work if there was no glass.
So I reduced the Mask Density to 50% in Mask Properties. You can adjust this to suit.
I hope this helps, but please ask if you need anything clarified.
... View more
AdChoices