May I ask how to create a camera using fisheye lens with 180 degree of view in Houdini ?

Thanks!

Ji

Set the focal length to 1 this should give you the effect you need

Thanks, Fromhell! however, I still can't render a fisheye image out the setting you suggested? can you shed more light?

have a look at the scene file

You need to add the rendering parameter vm_curvature to your camera and play with that to get a fisheye lens effect.

edit: I'm sorry I didn't realize that this has been posted in the Apprentice section. To add rendering parameters you need to click on the gear menu on the top right of the camera parameters and select “edit rendering parameters”. In the dialog select Mantra11>View>Lens Curvature. And then either drag and drop it or right click and select “install parameters” to add it to the camera's interface.

-dennis

Thank you, fromhell and dennis! will try accordingly later.

Wanted to bump this topic since I can't seem to achieve the proper look based on Dennis' instructions.

Basically I'm trying to achieve something akin to this:





Any additional help is much appreciated as always.

Midphase
Wanted to bump this topic since I can't seem to achieve the proper look based on Dennis' instructions.

Basically I'm trying to achieve something akin to this:





Any additional help is much appreciated as always.

If you know what type of projection that lens uses, you can find the math for the projection by searching. Some of the popular projections are easily found as source code for lens shaders for other renderers. It is then trivial to translate to VEX in a lens shader for mantra. It's less trivial to translate mathematical formula to shader code, as they tend to be written in terms of complex numbers. The houdini docs list the specification for custom lens shader. There are a couple built in that you can examine the source code to see where to insert your own projective transformation.

http://mattebb.com/blog/weblog/houdini-fisheye-camera/ [mattebb.com]