Hey everyone, I'm new here and I got some general questions to a 3D workflow.

I've been doing photography and photoshopping everything for 6 years now, I so I'm pretty comfortable with it. I've also been doing after effects based motion graphics and compositing for a couple of years now, so I know my way around AE and how to fit 2D objects and indeed to some extend 3D objects in an existing scene. I know how to motion track stuff (I'm okay I know the basics and how it works and done a couple). I've also modeled and textured a bit in maya and I'm also familiar with maya rendering procedure in general (certainly not very good but eventually I get where I need to go) Mainly to integrate some 3D elements in existing footage. I'm saying all this since you kind of need to know what I know to answer my question.

I'm completely new to houdini and I'm not really so good at the 3D side of things so I can't really extrapolate from what I know and apply it to houdini. But here's what I know about a 3D workflow.

First comes the modeling and texturing of your 3D objects. Then you need to light it properly and animate and then render it. After that is all said in done you need a compositor to place all your elements in your scene (so that's the rough scheme of things).

What I'm wondering now is, if you don't want to integrate 3D objects in your scene but rather build an entire 3D scene from the ground up. How do you go about it? For example lets say you build a scene in which two people have a conversation in front of a fire place and that's all 3D. Do you first model every bit and put it in one complete scene and render everything in one go, with all the particles etc included? (except the 2D assets I guess) Or do you render each objects separately and piece everything together in the compositor to then render the final image? (I would think not since a ray tracer needs the other objects to be included to work out reflections and stuff) And what about particle simulations? Are those rendered separately with simple objects to take the main objects place?
And on a side note to that, which compositor would you say is a good one? From what I've read AE is not really suited for 3D work, no unified 3D field and all that and the built in houdini compositor is more of a rough estimation rather than for your final composite.
From what I've read NUKE is supposed to be a good way to go, but I'm sort of confused on what it's purpose is exactly. I mean I've seen complete 3D models in NUKE's window, like it's used to place a complete model and composite with that. (I always thought the 3D program renders 3D scenes and you piece them together with your compositor?). And apparently it also has it's own particle emitter and particle system. Do you render your particles in houdini or the final compositor? Or do those two particle system have separate uses? (One for complex 3D simulation and one simple one to add extra effects would be my best guess?)

I know it's a lot but those are the questions that came up during the first times I played around in houdini.

Thank you.

Hey man,

A lot of questions here, but…

What you render in which order is pretty much dependent on what your actual Scene looks like. So you can't really apply any rules here.

You can render everything out in on go but add special passes that will aid your compositing. So to stay by your example it can be useful to add Object/Buffers for your Characters, so you can color Correct them seperatly.
But if your Camera is not moving it can sometimes make sense to render the BG seperatly, as you only need one Frame.
This all really comes down to the actual scene.

If you are just starting out, After Effects is fine! Especially if you know your way around already.
Simple Compositing can perfectly done here!

Nuke is in fact a more advanced option. But genereally you will render all your stuff in Houdini, Maya, etc and then Comp in Nuke/AE.
Sometimes it can for simple stuff just be faster to add some Particles with sprites in Nuke and not going back to your 3D Package.

But try looking for example at the beginner Tutorials by the Foundry or SideFX and start slowly. They will get you the understanding you need. Just because there are features like DeepCompositing they are not really the place to start.
But of course feel free to keep asking!

Alright thank you for the answers!

Heavy VFX (like massive smoke explosions) can be rendered separately and composited in. Especially since that sort of thing can make a big impact on render time and can be composeted in relatively easy. Aside from that you would usually have everything in one scene, or reference it into the same scene at render time.

Houdini has decent compositing tools. They may take some getting used to. But that's true for everything in Houdini.

Before you go into compositing, you will first have to:
Model
UV
(Possibly remesh and bake textures)
Texture
Set up materials
Rig (optional)
Animate (optional)
Render
- That's several years worth of education for just the basics, if you want professional-looking results. Just a fair warning.

When you say, education, do you mean formal education in college or just generally speaking learning Houdini, self taught or formal?
I'm currently studying CS and I'm basically teaching myself (through Internet resources of course) or do you think that's not enough?

You can teach yourself, but a good formal education gets you to a much higher level much faster. There are differences between people, though. Some can learn on their own with online tutorials and forums and whatnot. - in fact you will do the same in a formal education, but you get more structure from teachers and assignments.
Personally I tried to teach myself for about a year, then went to IGAD NHTV in the Netherlands. Was there for 4 years to get my degree. Even though I already knew some stuff, it was really tough. Now, I'm still learning new stuff practically every day.
It is very difficult to find a good education in the field. Many CG school are little better than scams, because they don't really teach you useful skills and are very expensive. Anyways, you will want to find a school that focuses almost entirely on practice and project work, has a curriculum with strong focus on the field that actually interests you, is not expensive (because you might not find a job afterwards anyways, or decide to abort the study) and has a good reputation for putting out skilled students. If you go that route I highly recommend to invest time into properly researching the right school for you.