Environment moves in my animation

[JAKiii]

So here's a question: I ran this animation test using an aircraft hanger environment and no backplate.  The animation is a short camera move, and as the camera swings around, the ground plane in the environment moves underneath the model.  Is there a way to prevent this?  Or is this a limitation of lighting with environments?

Thanks for any help,
Jamie

[KeyShot]

Check 'flatten ground' in the environment tab.

[JAKiii]

Flatten Ground is no good, it distorts the environment and only works if I use a backplate.

Before and after flattening ground, see below:

[PhilippeV8]

what if you increase environement height ?

Love the plane by the way !  Good textures.

[JAKiii]

Good idea, raising the environment height worked to some extent, but the floor is still distorted and the black circle is still a problem.

[PhilippeV8]

Ok, from now I can't help anymore.

So, Mr Keyshot folks .. how to get this perfect ?

I wonder ... it looks as though the HDRI, which is projected on a sphere; when enabling "flatten ground" gets a flat spot at the bottom and the texture of the HDRI is stretched.  There should be a better projection when using this option.  Can it be done ?