View Full Version : Turning off the Horizon - How?

12-27-2004, 09:33 PM
I don't use LW very regularly, and know I have done this in the past.

How do you turn off the horizon so that it gets ignored if you are making an alpha channel or have a background image?

I have the camera slightly above the horizon and tilted down, so the horizon fills about the bottom third of my screen, and I just want it to go away.

Thanks in advance.

12-28-2004, 12:44 AM
Reading my own message, I guess to be more specific, I am talking about turning off the ground, not the horizon...

12-28-2004, 05:18 AM
Your question is kind of vague. Is this what you are refering to? If so, adjust the colors in your backdrop. Copy the sky colors down to the ground colors as indicated.

12-28-2004, 07:32 AM
No...I was probably tired when I posted that. That's not quite what I mean. I attached an image of the problem below. This is an example frame output of a 32 bit TGA (with Alpha). It properly lays over the winter scene from the horizon up, but the ground area has an Alpha just like the characters. Which isn't the intention.

I even tried cheating by just having the winter scene be the background image, but the ground showed up just the same. I essentially just want Lightwave to ignore the ground so it will be keyed out just like the sky is.


12-28-2004, 10:33 AM
How did you place the image in the background for this scene?

12-28-2004, 11:13 AM
post your Alpha.

12-28-2004, 01:03 PM
OK, here is the seperate TGA alpha. I had it create an alpha separately for this example frame. The 32 Bit TGA output has one embedded in it, but I created this one to show you.

And how did I put the background in? I tried it two ways, one by choosing the winter scene as the background image in LW, and then also trying compositing the two characters over the background in another software package (laying it over the winter image with an alpha channel to cut it them out).

I know this is possible because a year ago I created a bunch of animations where there was an alpha channel and did not have an issue with the ground getting int he way. Unless maybe the camera position never showed the ground. But come on, there has to be a way to get LW to ignore the ground on output renders. I only use LW sporadically, so I know there are plenty of holes in my knowledge of the system, but I know this has got to be possible.

Thanks in advance again!

By the way, this alpha channel is not for the *exact* same frame as I showed earlier (above), but very close.

12-28-2004, 01:31 PM
that is very strange. You don't have a "ground" object of some kind in there??? I will try this when I get home and see if anything weird happens with mine.

12-28-2004, 01:43 PM
Crazy. I am the first to say I am no expert at Lightwave, but I thought I at least at one time knew the basics.

Here is my latest problem. With this same scene, when I try to add additional lights, LW just ignores them. They will be there in the interface, I can point them, change them, etc etc. It's just that LW completely ignores them in the Open GL display and on renders. The original first light is fine, I can affect it anyway I want and it does show on Open GL and renders. But if I, for instance, turn the light 1 off, and then take the second additional light and point it a meter away at the subject, nothing. Zero zip.

If I clone light 1, it does the same. Is there some setting that limits the number of lights in a scene (in my case, to one). Maybe part of the problem is that a year ago I migrated LW to a different computer (yeah, I use LW alot...first time in a year I'm using it!) and did maybe some of my default settings (that I used to know about) go to factory defaults?? I am grasping at straws here...

12-28-2004, 01:51 PM
you can limit the amount of OPEN GL lights but that has no effect on final render. All of the light intensities are high?? You're sure there's nothing in your scene besides your characters? Now I'm grasping :)

12-28-2004, 02:19 PM
Again, I'm no expert, and don't use LW that much to be sure, but something is whacked on my system. It is generally working, but it is doing some totally off the wall things...namely ignoring lights and refusing to ignore the ground. The more I use it today, the more remember, and it's just not right.

Does anyone know of some sort of hardware incompatibilities? It used to work fine last time I used LW a year ago or so on a HP 800mhz Athlon using Windows 2000. Now I am using a Sony 2.5 ghz using Windows XP Home, and it is working but acting strange. Whassupp????

12-28-2004, 04:12 PM
You may need to increase your segment memory limit on your camera properties. I've seen similar problems when you render in multiple segments. Just increase your memory segment ot 64 MB or 128 MB.

12-28-2004, 05:14 PM
Delete the polygon(s) you are using for a ground plane.

12-28-2004, 05:29 PM
No polygons are in the ground plane.

I made the changes Puma suggested, and restarted. And it seems that lights are working properly now and the Alpha channel is working.

And then the alpha channel wasn't working.

So I started again, and then built up to where I was in regards to tweaks and adjustments, and did a test render after each one to see where it goes wrong.

But then it came to me that I was always thinking of adding fog, but never used it after fiddling with the settings. I always turned the fog back off (Fog under the Scene settings). But even though I thought I turned it off, no matter what I did the ground would render over the background (be part of the alpha channel).

SO...this is it. Is there some trick to turning fog off? I mean, like as if it had never been clicked on in the first place? Because every time I click on it, and then choose to turn it off, it creates the above problems (in the pictures).

Solve two problems, come up with one new one. That's going in the right direction at least...

Well, the ground fog that is the problem can have opacity set at 0% I just noticed/found. So that solves that.

Man...what a pain in the a**. No wonder why I only have time to specialize in television editing, and not be a 3D guru. Oh well...so here it is...minus the evil ground fog and with *two* lights...

12-29-2004, 01:52 PM
That's one happy snowman. :D

Glad things are working better. -MG.

12-29-2004, 06:04 PM
The only way I can see fog interfering like that is if you are using an object to place your background. If you do not need to cast shadows onto the background, you can set your image as background rather than on an object. Which would do away with fog interfering with the background.
If you select WINDOW>VOLUMETRICS AND FOG OPTIONS then you can set fog type to off or remove volumetric fog from list at the bottom of this panel.