use background shader issue.

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# 1 08-06-2010 , 06:58 AM

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Location: Illinois

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Hi Everyone,

Been a while since I posted, I am having a problem with the use background shader. I am using it to get shadows under my robot but they are not showing up. The shadows are on the model but not on the ground. I have attached a image of my render and a screen shot of the settings for the use background shader. Any help would be appreciated.

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# 2 08-06-2010 , 07:04 AM

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screen shot

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# 3 08-06-2010 , 07:01 PM

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are you using mental ray ? if so you need the IBL node to make the magic work. Use final gather and the shadows should appear.

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# 4 08-06-2010 , 09:23 PM

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I am using mental ray, but I don't know what the IBL node is.I will try using final gather.

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# 5 08-06-2010 , 09:30 PM

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I see what your talking about now. I am not using image based lighting. I have used direct lighting with a background card to achieve my effect. Maybe I will try image based lighting. I don't have any suitable hdr's though, and I am not willing to pay for one LOL!

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# 6 09-06-2010 , 05:05 AM

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You don't need HDRI for this.

Create a plane underneath the robot to catch the shadows; then assign your use background shader to that plane.

Take a look at this tutorial: https://vimeo.com/2327952

Imagination is more important than knowledge.

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# 7 09-06-2010 , 10:33 AM

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HRDI, no no no!!

yeah just do what NextDesign says and problem is sorted.

Jay

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# 8 09-06-2010 , 02:07 PM

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Thanks Jay and Nextdesign for the tips, but I actually tried this but for some reason the shadows don't work on the use background shader when I am using mental ray or FG.

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# 9 09-06-2010 , 03:05 PM

Lead Modeler - Framestore
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It should work.

Dont forget that FG isnt a direct light source, its just occlusion so may not show as prominent, throw in a spotlight to make it work better

Jay

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# 10 11-06-2010 , 12:39 AM

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If you PM me the file I'll take a look into it for you.

Imagination is more important than knowledge.

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# 11 11-06-2010 , 01:11 AM

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Hi, if you're only using mental ray and FG, you probably just need to go to your camera attributes and change the environment color from black to white. Just guessing though...I don't see any reason for it not to work like you have it though.

edit: I just tried with both white and black environment and it works both ways. If you can't figure it out, might want to do like nextdesign said and send him the file to look at for you.

Don't be satisfied with what you can do but rather strive to do the things you can't do!
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Last edited by Perfecto; 11-06-2010 at 01:17 AM.

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