You can get a shadow with an HDRI. But it depends on the image and what kind of lights are in the image. In this first one, it's an indoor room with a window to give light. The shadow is very faint. It probably wouldn't have shown up if I'd bothered to line her up with the floor.

This second one is the same scene with a sunny outdoor image. You can see the shadows much better. The shadow is at a different angle because the sun was in a different spot than the window.

This is the setup of the scene. Lights 1-4 are "work" lights that light the preview but don't render. The main light is my starting point for lighting a render until I have the proper lights set up. It's turned off for these renders. All the light and shadows are from the HDRI on the background texture. The setup was based on the Mondello beach scene that comes with Poser.

---

Available on Amazon for the Kindle E-Reader Monster of the North and The Shimmering Mage

Today I break my own personal record for the number of days for being alive.
Check out my store here or my free stuff here
I use Poser 13 and win 10