Making Objects Look Realistic on Imported Backplates

[DESIGNERDREAD]

Hello!
How do I get a shadow(s) on the objects that I render over a backplate? For example in the image below, there are no shadows being cast on the floor from the chairs.  Additionally, I'm not quite sure if my chairs are scaled right. The chrome base is about 7inches tall....does that dimension look like it is being expressed in the picture? Thankyou so much for your help.

[NM-92]

Hey. First of all you have to make sure your models are not flying around, so make sure to snap them to the ground in order for them to cast shadows. Having an actual surface on the scene acting as a floor can also help with this if you use an occlusion node to enhance the shadows. Regarding the lighting issue, it's always the best to have a set of matching HDRI + Backplate for optimal results. In case you don't, you'll have to create your own HDRI using the editor to match the lights properly, but notice you won't have any reflections from the environment itself. It's a tricky subject, but you can achieve nice results some times. Others it's just impossible and you'll have to find a better or less complex backplate. Cheers, hope it helps !

[DESIGNERDREAD]

Thanks for your response! I did "snap to ground" the objects. In regards to this: "having an actual surface on the scene acting as a floor can also help with this if you use an occlusion node to enhance the shadows"? How do I achieve that via the occlusion node? Also, do you think my chairs are scaled good enough being that the chrome base is about 7 inches tall?

[NM-92]

I attached three images to show you how i use the occlusion node in this situations. You can see the difference between the model "floating" in the air (snapped to the ground) in the first image, without a surface below and the same model and lighting but with a ground plane and an occlussion node on the second image. I ussually use a plastic material (you can use whatever you want) for the surface acting as the ground plane, and I connect the occlusion node to the opacity channel to hide everything but the shadows. You can see that on the third image. Then you can tweak the node settings to make the shadow sharper.

Regarding the scale, i don't have anything in the room to compare to, so it would help if you populate the scene or use another backplate.

[Danthedesigner]

I attached three images to show you how i use the occlusion node in this situations. You can see the difference between the model "floating" in the air (snapped to the ground) in the first image, without a surface below and the same model and lighting but with a ground plane and an occlussion node on the second image. I ussually use a plastic material (you can use whatever you want) for the surface acting as the ground plane, and I connect the occlusion node to the opacity channel to hide everything but the shadows. You can see that on the third image. Then you can tweak the node settings to make the shadow sharper.

Regarding the scale, i don't have anything in the room to compare to, so it would help if you populate the scene or use another backplate.

Thanks for this great tip!

[Will Gibbons]

FYI... look at the bottom of the Environment settings. Occlusion Ground Shadows is something we added for KS7. Simpler, but less customizable.