Attached Link: http://www.renderosity.com/viewed.ez?galleryid=1163788&Start=1&Artist=vangogh&ByArtist=Yes

Since I posted my latest image I have had two comments asking why I used so many volumetric lights to achieve the light rays effect. the answer is that it was the only way out of several dozens of attempts that I tried that seemed to work the way I wanted. Lighting has always been my Achllies Heel and always seems to drive my up a wall no matter what type of scene I am working on, but this one in particular took alot of time and sweat to achieve. first I tried using one parallel light directed through the window from the outside. This one worked sort of kind of, once I realized that the sun had to be disabled before the rays would be visible. But I couldn't have cast shadows and or receive shadows enabled (in the materials lab window) because either the light rays were broken up or else the areas where the window dividers should have blocked the light rays weren't there. And if I had shadows enabled in the light lab then the rays would disappear altogether. I ended up trying so many different combinations in either the light lab and the materials lab that I soon became frustrated and went to bed with a troubled mind that night. At around 4 am I awoke with a start and another idea to try. why not have 2 lights - one for the rays and another separate one to cast the desired shadows on the floor. This worked great up to a point. I had shadows being cast correctly on the floor and also light rays that were unbroken without strange shadows being cast on the rays themselves. But there was still no indication of the rays being interupted by the window dividers like there should have been. Then I had another sleep interupting idea to try putting one light just big enough to shine through one pane only and then dup that light 10 times and put one behind each pane so that the dividers would appear to be blocking the rays correctly. As for render time, surprisingly, there was very little difference between using just one volumetric light and using 10. The volumetric material used was the default one assigned by the light lab when selecting the volumetric option. this is the solution that worked for me. I would love to hear about any other ways that anyone else has found to work for them.

A single spotlight, with the 3 options highlighted in yellow activated. That's about it. If I want the volumetric light to look as if it is traveling through smoke, I go back to the main screen with the spotlight selected, hit ctrl+m, and apply one of the preset volumetric mats (smokey light #1, #2, etc), tweak it if neccessary, and again, that's it. *Additionally, there was a radial light in front of the window with shadows de-activated and set to an intensity value of 1. Otherwise, the window/wall itself wouldn't show up too well. Render time = 2min 9sec AgentSmith

Message edited on: 02/24/2006 14:56

Hey thanks Agentsmith. I never knoew that, or if I had I had fogotten it. Cool. David

Thanks AS.....I had the same three options selected also, but still had troubles with unwanted shadows on the rays themselves. To get consistant rays along the full beam, I had to deselect the three options in the pull down menu that is to the left of the texture editor in the materials lab window. Also of note....in the complex materials lab library there is a texture that is listed as great for applying to lights to get rays....and indeed they do look great in the material lab window....but disappear in the scene window. I tried using this one with every option I could think of selected or not selected at various times with no luck.

Well, it does look like you have glass in your window, lol, so that can complicate things. That could be why you had unwanted shadows on your light rays, and what you did was the correct fix. ;o) A lot of times, the volumetric mats that are for light rays; unless its a very dark scene mine above, I almost always have to take their base density to 100, their edge soft to zero, and their fuzzy factor also to zero, etc, etc...basically everything I can do just to make them show up! Most of the time, also using a light with the above mentioned 3 options clicked off will do it. A few times, I had to take the light to a falloff of "None" to make anything show up. Volumetrics are a tricky bunch. AS

if you do a search on google for Peter Sharp/sharpe which ever way you spell his surname you'll find a tutorial on there about using the same lighting effect. You can use a single parallel light to give you the same effect as the one AS showed you :)

I have a a few images in my gallery with some single spot volumetrics. I use similar settings as the ones above in AS' post, except for the infinite. I usually used falloff>ranged and adjust the numbers to suit.

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