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Mr Maze
02-26-2007, 09:08 PM
Hi everyone,

I am currently working on a lighting tutorial for a photographer, making scenes and animations which show his lighting setups. I want to have a softbox that I have made be volumetric, but am unsure how - it would be easy if an area light could be volumetric but render times would be intense...

I have tried a few different things but just started using Lightwave last year so there is probably something obvious I have missed. Included is the softbox itself without any kind of light (modeled object such as a strobe or a hot light) attached to it. The white part of the softbox has high luminosity and diffuse so that it looks like it is lit up.

43096

Thanks for any help

toby
02-26-2007, 11:18 PM
You really want volumetric lighting? Basically you want it to look like it's in a fog?

Anyway, use the "Cone Base" setting in the volumetric options, it allows you to set the beginning of the volumetric light at a distance from the light. This means it will start at any size you want, not just the point of the spotlight or point light. You then place the light behind the lighting instrument, turn off diffuse and specular so it doesn't light up it's back, and the volumetrics will appear to emminate from the lighting instrument. To get the shape of the light cone to be rectangular instead of round you'll have to create a projection image.

To try and keep the render fast, avoid raytraced shadows.

Mr Maze
02-27-2007, 08:26 AM
Exactly. Thanks Toby. I was actually playing with the cone base setting but looked right past turning off the diffuse and specular - so I wasn't putting the light far enough back. Also didn't know I could do that with a projection image, should be easy now.

Mr Maze
02-27-2007, 02:05 PM
Example render of what I wanted to do...

43133

toby
02-27-2007, 09:32 PM
Of course, makes perfect sense, I just couldn't picture it. Not enough time spent in a real studio -
Looks great!

Mr Maze
02-27-2007, 11:36 PM
Thanks Toby I will post an animation for you tomorrow if I can...Worked on it today until my fingers wouldn't fing

ndrangesh
03-01-2007, 05:12 AM
G'Day mate
you can create this volumetric effect using "edge transparency" in the shading tab in the surface editor

create a box taper the back end to fit the monitor and set Luminosity to 100 and diffuse to zero apply edge transparency
saves rendering time a lot with a good looking volumetric effect
i'll post an example of it tomorrow

bob anderson
03-01-2007, 05:00 PM
G'Day mate
you can create this volumetric effect using "edge transparency" in the shading tab in the surface editor

create a box taper the back end to fit the monitor and set Luminosity to 100 and diffuse to zero apply edge transparency
saves rendering time a lot with a good looking volumetric effect
i'll post an example of it tomorrow

This WON"T work, as edge transparency only works on greater than 90 degree edges. The box winds up looking like a box.. On the other hand, if you create a box with radiused corners, it works fine. And you are absolutely correct that this renders in 1/10 the time as a volumetric.

Bob Anderson

Mr Maze
03-02-2007, 08:53 PM
ndrangesh:

When you gonna post that example?

ndrangesh
03-03-2007, 05:11 AM
yep
sorry i forget to mention the rounding the edges
i will post yours tomorrow
sure