tilt-shift lens in houdini

[jon3de]

is it possible to tilt-shift the lens somehow in houdini to force this effect ?

kind regards

Jon

[konstantin magnus]

Hi Jon,

try "screen window x/y" for offsetting the camera. 

[jon3de]

hey konstantin,

Thanks for you tipp. I think this just shifts the view right? I search a way to "correct" the diagonal lines ( which are obviously correct )  to perpendicular lines. Basically what a tilt shift lens does. If you are familiar with the e.g. vray physical camera there is a vertical tilt parameter which let you distort the view exactly like in the picture above. 

[3dome]

you could go to your camera, add Lens Curvature (vm_curvature) from the Rendering Paramters and adjust that, or you use a ASAD lens shader (or build your own). To use it, camera under View -> Projection from "perspective" to "lens shader"

[DaJuice]

The Screen Window X/Y settings will do the trick, it just isn't represented properly in OpenGL if I remember correctly.

[howiem]

Don't forget that the camera angle is what creates the convergence (well, mostly). If you shot the building straight-on perpendicular, verticals would be parallel: but you can't do that from ground level; so you end up tilting the camera up to get the whole building in. A tiit-shift lens, apart from giving funky focus effects, is designed to let you reframe a shot without having to angle the camera. So put your camera in position, but point it straight forward. Parallel to the ground. You won't have the whole building in frame at this point, it'll be mostly ground and bottom floors, but vertical lines should be parallel. Now you can do the magic: shift the film-plane to actually frame your shot, extending it up to cover the building and to crop out the ground. You haven't changed any angles, you've just extended your frame up. Ta-da

[Mark01]

You could use a shader to undistort the image and and remove the natural lens distortion then perhaps create the tilt shift distortion afterwards in AE or Nuke?

Let me know how you get on