Render elements

[Crayox13]

Hi,
I just read somewhere Vlado saying how a certain element should be added in a certain way in PS. So it made me wonder, is there like a tutorial about this? How each of those elements should be used, when, and why?

If not, maybe you guys could share some of your techniques for us? I hope this is not like asking a cook for a secret recipe even though it IS in a way.

[tricky]

This is a topic that comes up time and time again on this forum. As of yet, I've not found a simple answer, apart from buying Cebas PSD Manager (but nobody really wants to do that as you should be able to do it manually quite easily - as it happens, you can't [easily, I mean]).

[Crayox13]

How come Chaos doesn't have any help for elements and how to use them? Vlado, any plans for that?

[Morne]

they don't believe in instruction manuals. (spot3d is not an instruction manual but merely a vague reference for advanced users) That's why we have books like the one from that italian guy (sorry can't remember his name now)

[Olli96]

Cecufuli or Francesco Legrenzi is his name

I dont often compose my images with different layers but if i do it thats how i do it:
Raw GI x Diffuse = GI
Raw Light x Diffuse = Light
GI + Light = "Image"
Then you add the reflection layer, the refraction layer, specular, self-Illumination Layer and in the end you should come up with an image very similar to the final render from max.
If you want even more control about your passes then you could multiply the Raw Reflectoin pass with the Reflection Filter, which ends up in the Reflection Pass, same goes for the Refraction pass.
I am not sure if this is really "THE" workflow for this, but in the past this worked for me.

[Crayox13]

Hi Olli96, thanks for sharing your experience. In PS language, multiply is I guess multiply but add is Linear dodge (add) or? When I did my renders I always did things (added layers) to a normal render, but now I see I should use "raw" diffuse, and not the final render which already has all in it.

@DVP3D hahaha yes, I noticed that But seriously they should do at least something. Spot3D is actually quite helpful, I use it often, but it still doesn't have everything covered.

[Olli96]

I do mostly Archviz and to be honest i usually use the final output and add passes on top of this like you do.

[Crayox13]

Oh, and I just saw there is no Diffuse, there is only raw diffuse filter, whatever that is Vladoooo, we need help fileeee

[vlado]

The general formula is this:

result =
   background
   +
   lighting
   +
   globalIllumination
   +
   caustics
   +
   reflection
   +
   specular
   +
   refraction
   +
   sss2
   +
   selfIllumination

Some of these components can be replaced with a composite based on a raw element
and a filter:

lighting=rawLighting*diffuseFilter
globalIllumination=rawGlobalIllumination*diffuseFilter
reflection=rawReflection*reflectionFilter
refraction=rawRefraction*refractionFilter

So, for example you can get a formula like this:

result =
   background
   +
   lighting
   +
       (rawGlobalIllumination
       *
       diffuseFilter)
   +
   caustics
   +
   reflection
   +
   specular
   +
       (rawRefraction
       *
       refractionFilter)
   +
   sss2
   +
   selfIllumination

And so on, depending on what you need to adjust.

However, I would not recommend using the "raw" elements from V-Ray
directly, as they need to be multiplied by the corresponding "filter" element
which may lead to edge artifacts. Instead, using the formula

element=raw*filter

(e.g. reflection=rawReflection*reflectionFilter), you can derive a raw element
from the normal element and the filter:

raw=element/filter

(e.g. rawLighting=lighting/diffuseFilter)

Then you can perform any color corrections on this raw element and/or its
filter, and them multiply them together again and add to the result. So the formula would become

result =
   background
   +
   lighting
   +
       ((globalIllumination/diffuseFilter)
       *
       diffuseFilter)
   +
   caustics
   +
   reflection
   +
   specular
   +
       ((refraction/refractionFilter)
       *
       refractionFilter)
   +
   sss2
   +
   selfIllumination

All this math is best done in a proper compositing application like Nuke; you can probably use PhotoShop, but it's not really designed for this.

Best regards,
Vlado

[tricky]

The general formula is this:

result =
   background
   +
   lighting
   +
   globalIllumination
   +
   caustics
   +
   reflection
   +
   specular
   +
   refraction
   +
   sss2
   +
   selfIllumination

Some of these components can be replaced with a composite based on a raw element
and a filter:

lighting=rawLighting*diffuseFilter
globalIllumination=rawGlobalIllumination*diffuseFilter
reflection=rawReflection*reflectionFilter
refraction=rawRefraction*refractionFilter

So, for example you can get a formula like this:

result =
   background
   +
   lighting
   +
       (rawGlobalIllumination
       *
       diffuseFilter)
   +
   caustics
   +
   reflection
   +
   specular
   +
       (rawRefraction
       *
       refractionFilter)
   +
   sss2
   +
   selfIllumination

And so on, depending on what you need to adjust.

However, I would not recommend using the "raw" elements from V-Ray
directly, as they need to be multiplied by the corresponding "filter" element
which may lead to edge artifacts. Instead, using the formula

element=raw*filter

(e.g. reflection=rawReflection*reflectionFilter), you can derive a raw element
from the normal element and the filter:

raw=element/filter

(e.g. rawLighting=lighting/diffuseFilter)

Then you can perform any color corrections on this raw element and/or its
filter, and them multiply them together again and add to the result. So the formula would become

result =
   background
   +
   lighting
   +
       ((globalIllumination/diffuseFilter)
       *
       diffuseFilter)
   +
   caustics
   +
   reflection
   +
   specular
   +
       ((refraction/refractionFilter)
       *
       refractionFilter)
   +
   sss2
   +
   selfIllumination

All this math is best done in a proper compositing application like Nuke; you can probably use PhotoShop, but it's not really designed for this.

Best regards,
Vlado

Simple answer then

[Crayox13]

Now that's something that should be put immediately on Spot3D or a sticky for elements. Now all those make sense. Thank you very much!

[Crayox13]

Hm, Nuke is a really expensive piece of software, especially if I would use it just for merging elements. What is generally used here?

[trixian]

What about pd player? Would it be able to do this correct? (nested layers with different operators....+\-* etc)?

[vlado]

No, pdplayer doesn't do nested layers, so not all combinations are possible to implement - only the ones were there is just one multiplication that can be put at the bottom top of the stack are possible.

Best regards,
Vlado

[rayo-v]

Hi there,
I do mostly use Nuke for composting elements but if you guys need a cheap alternative Composite which comes with Max 2011 is as good for this, and is node based as well. I recommend it...