View Full Version : lighting question

05-10-2003, 06:24 PM
What is the best way to light 3d images in LW for integration into live video. My footage was shot outside w/o any lights other than the sun. Should I use a frame of the video and skydome it or are there any other techniques that might yield acceptable results. I'm looking for seamless integration here w/o radiosity, well, mabey background only radiosity if it looks good. I'll probably multipass the render and I'll definately be doing the compositing outside of LW either in AE or Combustion. I'm open to suggestions and if you have examples please feel free to post the here so I can see how they look.

05-11-2003, 07:57 AM
Try to match the lighting of the original footage, how you do it doesn't matter so long as the end result looks good!

Can't really be more specific without seeing the footage you have, every situation will be different.

05-16-2003, 11:38 AM
I'm learning this type of thing right now -
obviously try and put your lights exactly where they are in the footage - study the shadows carefully for clues. It took a lot of work to make the shadows look good - I rendered them in a separate pass and set it to "multiply" in AE - if the shadows have color it's more complicated.

The "spinning light" trick is really helpful in faking radiosity, where you spin the light 360' in 1 frame and turn on motion blur. I didn't use raytracing at all.

Other things that helped blend the CG into video - little bit of fog, blur and de-saturation

If you can photograph the area where the footage was taken to use as a reflection map it may help, there's almost always something that's reflective

05-17-2003, 06:43 AM
For fake radiosity check out EKI's plug-Pak for lightwave as it has a spinning light setup as a plug-in the web site is www.kolumbus.fi/erkki.halkka



Julian Johnson
05-17-2003, 07:47 AM
Toby - shouldn't that be 720 degrees in one frame if Motion Blur's at default 50%?

For coloured shadows, I use the shadow buffer as a stencil layer over a plate of the backdrop that I've cloned/painted darker (matching the real shadows in the scene by sourcing them with the clone tool and healing brush). Multiply tends to grey out the shadow too much.....but it depends on how much time you have.


05-17-2003, 06:36 PM
yes - I usually have motion blur set at 100% - pardon my boner:eek: