Distortion Viewport-->render ?

[Wingman3d]

I cant understand whats happening here. I'll try to explain.
To the right you see my viewport where i have lined up the circle on top of the glass.
Then i render, and you can see that it's a bit distorted.
And to the left you can see it composited over the glass in after effects, where it clearly doesn't match.

I'm using a vray camera with some distortion and vertical shift to match a real camera i have tracked, and i see the change in the viewport when i change these.

But i ran some tests, and it seems that it's the camera distortion setting thats causing this.
I have it set on 0,08 and cubic.
I got this number from Matchmover, and i think i've heard that cubic is the way to go with matchmoving.

If i render with zero distortion it comes out differently, but then it is as in the viewport.

Why isn't the render showing exactly what i see in the viewport when i use distortion on the camera?

[Wingman3d]

*bump*

Any technical explanation on this?
Any way i can fix it?

Vlado?
Can you try it out with a vraycam with cubic distortion around 0,08. Place a circle in each corner of the screen so that thay are tangential to the sides.
Are they tangential in the render?
Mine aren't.

[LarsSonparsson]

Distortion is raytraced and visible only in render.
Max viewports cant show those kind of effects.

It's not a bug, nor there is any way to fix it.

[Wingman3d]

But something is happening in the viewport when i add distortion. Things get distorted, just not the way it does in the render.
How can i use this when i dont know what comes out?
Any good techniques to use camera distortion when fitting 3d to matchmoved background then?
It seems impossible to use the distortion then when i can't match the 3D to the background.

Vray RT doesn't seem to use the distortion neither.

[joconnell]

The best way to do this is to undistort the images, track them, comp your 3d then redistort the images or use the same value to distort your 3d.

[Wingman3d]

i see, thanks!