Need some help with some very basic compositing

eponica

Hi again folks, ^_^

I am trying to make a scene with a lot of figures in it. And my computer only has 4 gb RAM. I've come to the conclusion that compositing the scene may be a good way to go. But I can't seem to find a good free tutorial on the basics of doing this.

Also, is there a way to render a scene in DS which will render the shadows of objects only, and not the objects themselves...?

Herald of Fire

Compositing is simply to break down any 3D image into layers which you can then combine later in a program such as Photoshop, Gimp or Paint Shop Pro. You render the background figures, then remove them and add the next set of figures closer to the camera, and so on until you have populated your scene. The trick here is to keep the lighting consistent throughout the layers and ensure that any shadows cast by the scenery or props are still cast onto those layers which need it.

It can be a very cost-effective way to render large scenes without a monster PC.

As for how to render objects' shadows without the objects themselves appearing, you can use the UberSurface shader provided with Daz Studio 4 or higher. In the surfaces tab there will be a 'Fantom' on/off switch. Switching this to on will make the object appear in raytracing but invisible to the render. This means it remains visible in reflections and for the purposes of casting shadows, without being directly observable.

mjc1016

eponica said:

Hi again folks, ^_^

I am trying to make a scene with a lot of figures in it. And my computer only has 4 gb RAM. I've come to the conclusion that compositing the scene may be a good way to go. But I can't seem to find a good free tutorial on the basics of doing this.

Also, is there a way to render a scene in DS which will render the shadows of objects only, and not the objects themselves...?

How big is your scene...and is your 4 GB on a 32 or 64 bit system? Windows (version)? DS (version)?

Scott Livingston

I posted this recently and thought I'd share a link here; it's a list of tips and tricks you can use to render a group scene with a slower computer. While it doesn't directly answer your question, I hope you find it useful.

eponica

Thanks so much for your replies ^_^

Herald, thanks especially for clueing me in on the UberSurface Fantom switch. I have been wondering what that did ^_^

Addict, my scene involves a large herd of animals, the ones in the foreground all have thick coats of Garibaldi hair and are pulling a wagon. About twenty lower-res figures will be in the background, with no 3d hair. Add to this four hi-res human figures, and some dust FX, and I am trying to do this on a computer that will only preview 3 human figures at most without bogging down. My computer: A (Walmart, reconditioned) Dell Optiplex 760 Core Duo, running Windows 7 Pro 64 bit with 4gb Crucial RAM. So I guess I had better learn how to do compositing now because this machine will only take 8gb RAM in total anyway... and I have no hope of buying anything bigger for the forseeable future.

Of course, I'd have some money saved up for that by now if DAZ didn't have such fantastic sales... ^^;

eponica

Scott, those are great tips. Thanks! I am using some node instances but I didn't know the difference between those and geometry shells. ^_^ Since each of my animals has a unique coat, the shells option looks quite useful.

eponica

Just had a hilarious mishap ^_^; Learned how to disappear my animal herd in the render but keep the shadows as we discussed (using Ubersurface & Fantom On) I forgot to fix the goat horns and udders though, as with these particular models they are not morphs but separate objects... So now I have a surrealist render with a bunch of horns and udders floating around in midair like balloons LOL LOL Would LOVE to post this but who knows what the TOS "thinks" of disembodied udders...?!

DAZ is great. I swear I haven't had so much fun since I was a kid. Even making mistakes is amusing! ^_^ (Wiping eyes)