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D.S.W.
02-06-2010, 01:04 PM
I've got a couple of ideas on how to do this, but it would be great if the professionals here could provide their input to obtain the best workflow. The software I will be using is LW, exrTrader (and possibly Janus) with Fusion6. If there's anything else that will help (and no, not Maya), please let me know.

-- Okay... this is an entirely CG scene. Several characters are walking/talking inside a hangar bay. I would like to use radiosity here as well. That's it. --

Now how would YOU break out this scene? Would you render the background separate and each character separate? Or the characters together? How would you account for shadowing on the characters from elements in the hangar and vice-versa? Would you lite the characters separately from the hangar? How would you lite the characters using radiosity? What about mattes? Separate llight passes? I would REALLY like to get a solid workflow down that has been tested by those who KNOW what they're doing! ;)

If there is anyone here who does ANYTHING like this - or just has a good workflow, your input would be GREATLY appreciated.:thumbsup:

Thanks!

SplineGod
02-06-2010, 07:41 PM
By and large such workflows are more or less determined by the desired result vs the resources you have available. The more data you can split out as separate buffers the more control that is possible. It also means having to track a lot more information, use more disk space and can, in many cases take more time. Doing things this way is more about control then it is about speed and generally works better if you have more ppl involvedl. :)

D.S.W.
02-07-2010, 12:09 AM
Exactly. I would like as much "control" as possible without going too overboard. Disk space is no problem - HD's are cheap enough. I would just like to get to the point where if/when I need to RE-render, the time required is kept to a minimum. I don't mind taking the time to set things up as well as keeping track of all data - that's not rocket science, you just need to be organized. I'd just like to know how others do this sort of thing - regardless of the number of people involved. I would like as much control over the final product in the compositor as possible.

What does the average professional do? What and why would they recommend a certain workflow?

SplineGod
02-07-2010, 01:41 AM
Under the Image processing tab----pixel filters there are various other savers....Deluxe RLA, PSD etc that support layered image filess. You might save out a Deluxe RLA file that contains the spec buffer, diffuse buffer, depth buffer and so on. It depends which buffers you need or the compositors require and the file format you/they prefer. Some formats support only 8 bits per channel and some support great bit depths. A commonly used format is EXR though the LW exporter doesnt support layers. DB&Ws Exr Trader plugin is probably the best option because it supports layers and floating point data (HDR)

D.S.W.
02-08-2010, 12:53 PM
I've been using LW for quite a few years now, so yes, I know about the pixel filters, etc. Thanks. And if you see in my original post, I will using exrTrader which will provide any and all of the layers I should need. Oh, and Shadermeister for ambient occlusion if I require that as well.

I'm not looking for GENERAL workflow with layers, I'm looking for a PRECISE workflow using layers. Such as WHAT layers are used and WHY they are used and HOW they can be used with a compositor such as Fusion. For example, Z depth is required(?) for changing the DOF and slightly blurring the background. And other things that professionals already know about what and why certain passes are needed.

If you refer back to the original question, I'd like to know...

1. Would you render the background separate and each character separate?
2. Or the characters together?
3. How would you account for shadowing on the characters from elements in the hangar and vice-versa?
4. Would you lite the characters separately from the hangar?
5. How would you lite the characters using radiosity?
6. What about mattes? Separate llight passes?

These are not questions that can be answered with "it depends on how much control you want" since I want as MUCH control as possible. I'm looking for detailed answers if possible, not an all-encompassing generic response. I'm not worried about the resources at the moment - that is something I will determine when I've got a pipeline. Heck, I might even rent a renderfarm. And since I will end up being the compositor, I'd like to know the options available and why they are used.

Essentially it comes down to this... if you had it your way, how would you break down the scene to provide you with the largest amount of control - regardless of time, space or complexity?

D.S.W.
02-09-2010, 12:42 AM
Seek.... and ye shall find. :)

This is a great FREE tutorial using render passes and Fusion:

http://vfxhaiku.com/2009/10/intro-to-multi-pass-compositing/

And while this one is $19 and deals with Cinema4D, AE & Fusion...

http://vfxhaiku.com/2009/11/advanced-multi-pass-compositing-with-cinema-4d-and-fusion/

...it shows most of the render passes and how they are/can be actually used (which is what I wanted to know) in a simple project. Although Cinema4D, the output would be the same as in LW and it is VERY much worth the $19! While articles in HDRI magazine and others are helpful, this one tutorial really shows the details - which compositing newbies such as myself can find extremely useful. Hopefully others will find it so as well.

Good Luck!

3dWannabe
02-13-2010, 12:12 PM
HDRI issue #30 might be useful, had an article about breaking out layers:

"Explore the new possibilities that Filter Node Editors provide for Multipass Rendering, Compositing, FX, and Color Grading."

http://www.hdri3d.com/index.php?option=com_content&view=category&layout=blog&id=163&Itemid=100

And there are several earlier issues that go into detail on that.

D.S.W.
02-14-2010, 12:05 AM
HDRI issue #30 might be useful, had an article about breaking out layers:

"Explore the new possibilities that Filter Node Editors provide for Multipass Rendering, Compositing, FX, and Color Grading."

http://www.hdri3d.com/index.php?option=com_content&view=category&layout=blog&id=163&Itemid=100

And there are several earlier issues that go into detail on that.

Yes, I've got that and I recall one of the previous articles written by Proton - got them! ;) This most recent article is very interesting, but I've found that most of the results can be achieved easily enough with exrTrader and Shadermeister with allot less time. The one thing all articles (at least those I've found) fail to show, is how these various layers can be used in a compositor. At least the two video tutes above show a few of these layers and how they are used and how they are blended together.

I am hoping that Kurv will come up with a few Fusion tutorials that deal with compositing these various layers. And of course if you know of any, please post them in this thread. So far I've found more specific info from the Making of Killer Bean Forever - which was VERY helpful but still did not contain enough info for all of the various layers that can be used. Even the "Art and Science of Digital Compositing" does not have that sort of specific information. Can anyone recommend a video or book that does?

3dWannabe
03-26-2010, 10:08 AM
I am hoping that Kurv will come up with a few Fusion tutorials that deal with compositing these various layers.

There are a number of videos here that show exrTrader/Fusion along with Janus in very great detail. There are 8 total videos, you have to look at several posts to find them.

http://www.newtek.com/forums/showthread.php?t=93407

I'm not totally sure I understand it all though. If you change the color of an object, wouldn't that affect the reflections in another pass?

The Z-Buffer Fusion tutorial was very interesting, but I'm going to have to watch them all several time to get my head around all this.

D.S.W.
03-26-2010, 05:04 PM
Thanks - already have them. :)

The problem is... there is not one tutorial "out there" that shows what ALL of the buffers from exrTrader CAN do. I've been experimenting using the various available tutorials (VFXjaiku, Kurv, CGSutra, etc.) and have discovered much, but much of it is really trial and error. Until someone comes out and renders out ALL of the available exr buffers and shows how they can be used, most of us will never know.

At least I'm moving forward! :boogiedow