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View Full Version : HDR/Light-Tracer/Enviro questions

ToddD
08-07-2003, 04:56 AM
Hey guys, I have a couple of questions.;) I've resorted to using HDR with light-tracer(slow pc owner, no brazil renders here)I am pretty happy with the lighting, shadows, and reflections I am getting. However, because I am using a low camera angle, I am seeing that ugly mess of a background from the enviro map. So, I would like to know if there is a way to have my vehicle be lit by and reflect the hdr, but not see it in the background, I'd be happy with a straight white or grey background(ala suurland's beetle)
Second Q, the other problem I am having is that the ground plane looks too sharp in the distance, any suggestions that aren't render time killers(dof is not an option, machine is that slow!)? I was thinking of making a long plane, and having it make a 90deg rounded radius type turn way off in the distance. As always I thank you for any assistance :beer:

EDIT: I would like to have the results in render as opposed to any post work in case I later animate a camera.
gaggle
08-07-2003, 08:04 AM
Good news, simply make sure the .hdr image is loaded in the Skylight's material-channel, then reset your environment's material-channel, and voila, the Skylight will light your scene with the image, but the environment itself will remain whatever color you choose.

At times it can work nicely if you set the environment color to the same as the color of your plane, so that the two blend together and no horizon is visible.

Other than that, sure, a soft curve on the plane can work nicely. As can a Gradient Ramp placed into the Opacity channel, set so that only the immidiate surroundings of the object is visible, the rest fades out to reveal the environment color.
sledgeweb
08-07-2003, 12:53 PM
Rather than make the ground plane the same color as the environment, you can just give it a material type of matte/shadow. Set it up to receive shadows, and you'll have a ground plane that is invisible, except where shadows fall on it.
ToddD
08-07-2003, 05:31 PM
Gaggle, will my vehicle be reflecting the enviro color? I still want the reflections from the HDR as well. For the ground plane I think I am going to put some fog at the far end of the ground that matches the bacgkground color, someone suggested that in anther forum, sounds like it may be a good solution.
Sledge, not sure I understand that, I will have to give it a try sounds simple enough:)

EDIT. Here's a very small sample of what I have soo far, sorry about the size, but as I said my PC is a slug, so I do small tests before commiting to longer large renders.

http://www.vi2.com/getFile/246778.jpg
sledgeweb
08-07-2003, 06:20 PM
Hey Tbonz... funny how users here end up helping each other out. Thanks for you feedback on my sub-d thread.

OK, for the ground material thing. Hit M to open up your material editor. Select an unused material. Click where is says STANDARD. This is the material type. Instead of STANDARD, select MATTE/SHADOW. The default setting should be fine... basically, there is a option for receive shadows that should be checked. There is some other options, and I think they are off by default (matte options if I remember correctly).

Apply this material to your ground plane. When you render, the ground will not render except for shadows... allowing your background to show through. If you look in my Sub-D thread, the renders there were done like this.

If you put the environment map in your skylight settings as mentioned above, and set your environment color to a plain color, I believe it will use the reflection map during the render and just paint the background a flat color. But, I haven't tried it.

-Sledge
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