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JBT27
09-03-2015, 05:18 AM
I am trying to get a match back and forth between LW and Houdini - I'm new to Houdini.

FBX exports the focal length correctly, whereas Collada sets it to 50mm. In both cases the apertures are not exported correctly - I'm assuming that LW's camera frame property is the aperture in Houdini.

Also, via FBX, the imported scene in Houdini does not display the objects in OGL, whereas the imported Collada scene does.

Been thrashing round with this for some hours, searched on the web, but can't find much about it - would appreciate some help please.

Thanks.

Every4thPixel
09-03-2015, 06:44 AM
Take the horizontal field of view. It's an angle. That value should be the same in every app.

JBT27
09-03-2015, 06:58 AM
It's neither the horizontal nor the vertical FOV - tried it. I have matched in Houdini LW's focal length and angle of view, and frame size/aperture - doesn't match.

Every4thPixel
09-03-2015, 08:02 AM
If you match your focal length and you angle of view the frame aperture size should match as well. Or there is something really strange going on. I haven't got houdini so I can't check what settings are available but basically if houdini has an in put for horizontal FOV and vertical FOV I would use that because that value has no relation like the focal length and the frame size aperture have.

clintonman
09-03-2015, 08:30 AM
For FBX try setting the camera Screen Window Size to 1 and 1

For Collada note the Pixel Aspect Ratio and change it to 1 then divide the aperture by the old pixel aspect ratio. This assumes the aspect in LW is 1.



Set Resolution to match Lightwave Width and Height.

JBT27
09-03-2015, 10:48 AM
For FBX try setting the camera Screen Window Size to 1 and 1

For Collada note the Pixel Aspect Ratio and change it to 1 then divide the aperture by the old pixel aspect ratio. This assumes the aspect in LW is 1.



Set Resolution to match Lightwave Width and Height.


Thanks very much. In the FBX imported scene, Screen Window Size had come in the same as the frame size - 1920 x 1080 - setting it to 1 and 1 got the match. Much appreciated.