Im trying to make a solar system animation, and I’m using a blur in the compositor to add to the atmosphere look of earth, but I obviously don’t need it to be applying to the moon as you can see here:
Any way to make the compositor be selective about what it applies its blur or whatever effect to?
Additionally, I was trying to get the background star field to look realistic… the best way I could figure to do this was to create a super huge sphere with stars and milkyway texture mapped to it with it set to ‘Emit’ so everything glows. and it looks correct when I pan the camera around. Problem with this is, I cant get the blur in the compositor to work if its trying to blur objects inside this “star sphere”. Can I somehow keep the sphere without it affecting the composting?
You can use an object pass index on the moon. Or send the moon to another render layer. Then in your node system simply bypass the blur on the moon and mix it in ‘dry’, on top of the result you already have.
Like atom said, the easiest way is to move the object to a different layer and then do a separate render pass. If you haven’t composited with render passes before, it takes a bit of learning but there are some tutorials out there. PM me if I can help.
Awesome… got that render pass layers thing figured out, thanks for that guys… now I just need to figure out how to get the star sphere not to be affected by the sun light. If I put the light inside the sphere and make it a point light I can see the planet in the render, but if it’s set to sun, everything is dark - presumably because its shining from the outside, so its dark inside. If i turn off ray shadow it works, but causes some sort of brightness around the planet with the atmosphere layers (ray shadow looks better). Can I tell the light to ignore specific layers, just say don’t bother calculating the space sphere?
Are you using cycles or BI? The short answer is “yes”, you can tell it to ignore certain layers.
Basically, put the light on a separate layer and then tell the object layer to ignore/exclude the light layer (as I recall). I did this with a scene where I wanted the back wall of an interior to ignore the sunlight coming through the window.
hmm yeah, I’m rendering it using Blender Render. I can’t seem to figure that out though… seems like it should be easy to do. Does the space layer need to be rendered by itself also with render pass layers?
Sorry, I don’t have blender in front of me since I’m at work. I’ve done this in cycles and it’s easy because there are “exclude” buttons. In the BI, I think you use the layer masks?
If no one else replies, I’ll look at it tonight when I get home and post back.
Ok… so I think i’m getting closer… I have 3 layers moon, earth, and space. I have a light in the earth layer shining just on earth, duplicate light on the moon layer just on that, and the space layer by itself emitting light.
maybe somebody can help me get it arranged correctly, the space layer is sitting on top of the earth and moon layer, if I can get it behind them, I think i’ll be set…
OK, here is how I solved the selective lighting issue.
In the layer panel, there is a box for “light” and a box for “material.” These are overrides. So, make the light you want to illuminate the layer into a GROUP. Then, set up the layer as normal, but put that light GROUP into the light box. What that will do is use the light group to override the other lighting for that layer.
Play around with that and see what happens.
I set up a basic scene with 2 boxes and a sun lamp set to like 1000 to blow out the scene. I put the boxes on separate layers and the sun lamp on both layers. I then made another sun lamp and put it in a group. On one of the render layers I used the light group as an override and the other layer I left as normal. Even though the blown out lamp was on both layers, only one of the layers was rendered blown out. The other layer used the light group and ignored the other light(s) on the layer.
ok that works too… but i’m still running into the issue with the star layer looking like it wants to sit on top of the moon and earth layers, like in the last screenshot I posted. Is there a way to put that layer behind the earth and moon one?
In part you’re seeing the stars because you are using an Add node (lower right). The color of the stars is being added to the planet color. Try replacing it with an Alpha Over node. Also swap the inputs; in Blender, the image in the lower node is “closer” to the viewer (the opposite of Photoshop, eg).
It’s a good idea to build up a “noodle” one small step at a time. You are quite-literally writing a computer program, and you’ll need to debug it. Setting the “background” option is helpful so that you can attach a viewer-node at any point and see the result as your background on the node-editor screen.
I’m wondering if the fact the stars are showing up in front on the planet is because of some camera setting… I played around with the clipping, but that didn’t seem to help any. The camera is inside of the space sphere and in front of the earth sphere, so I just don’t get why I can’t just drop the earth layer directly on top of the space layer and have it block the stars behind it…
Is there maybe a better way to do the space sphere perhaps? like maybe somehow project it behind the entire scene, and tie it to just what the camera sees, and not actually have a physical sphere that its mapped to?
yeah if I flip them around, I just get the star field by itself (I guess the earth and moon are under it then), so I would think it’s on the correct orientation, but it still acts more like the add node rather than the alpha over node.
Just to make sure I wasn’t making it too complicated with a sphere and the camera’s position, I changed it to a basic plane and stuck it behind the planet as you can see on the far left 3d view window, yet it still tries to merge the purple layer into the earth layer… even though i’m using the alpha over node…
I appreciate it blenderjourney, thanks for the help you could provide! I might be in over my head with this composting editor… I’m still kinda new to it all.
Just a wild guess, but did you try enabling “All Z” in the Renderlayers tabs? IIRC, this should not render the background if there is something in front of it in another layer.
Hopefully someone smarter than myself can help you!