MultiPass Tutorial

[3dkobi]

Hi,

Here is a tutorial about using different passes in photoshop - very nice...
This guy works on max+vray and have some nice tutorials about vray for max too...

http://vimeo.com/13976235

It's the first tutorial I've seen that shows you what to do with the passes...

Peace,
Kobi

[Cometsoft]

Thanks 3dkobi, first one I've seen too. Very helpful.

[STRAT]

shame nobody as yet has come up with a workable solution for vrayc4d multipass :(

[3dkobi]

yes, it is a shame...
but as far as I know, the MP doesn't support AA so I don't see how I can use it for my stills or animation...I think it's a great tool but without AA its useless to me.

Peace,
Kobi

[STRAT]

even without AA i still havent found a tut that demonstrates how it all fits back together in photoshop 100% accurately. not even close. and without a system of rendering separate passes or layers and re-constructing them accurately in post then thats also a non starter.

[Tong]

http://www.render.ru/images/uploads/Image/Tutor/max/405/Elements.jpg


(Background+Lighting+GlobalIllumination+Refraction +Specular+SelfIllumination)*AO+Reflection

"+" - Add,
"*" - Multiply.

;-) additional passes if you want you can use, AO pass can be made with 1.3 vrayc4d ;-) with 2side material and vray dirt shader ((( because it more correct way, then use override or luminance material

http://www.render.ru/images/uploads/Image/Tutor/max/405/AO_render_s.jpg

[STRAT]

been there done that. rendering passes is easy, but de-con and re-constructing and accurate rgba image (as if it was a single pass) in post has not yet been demonstrated.

[Tong]

you mean like this?

http://img837.imageshack.us/img837/4017/1281448932clip165kb9266.jpg

[STRAT]

no

Tong, i'm not disputing the point with you, i'm just stating the fact there's not yet been 1 correct set of instructions or tutorial explaining how it successfully works. you showing the odd picture or 3 isn't demonstrating to me how it works or if it works.

we've had a massive on-going thread on this in another forum heading, but there as yet isn't a conclusion or a satisfied customer.

http://forum.vrayforc4d.com/showthread.php?t=4401

[Tong]

well ok, i will try to make psd file with channels that make exact rgb image, if i get it right ;_) and post it.

[STRAT]

then tell us exactly how you did it. ;)

[Tong]

sure the fish and fishing rod ;-)

[point08negative]

Hey Tong,
Im having problems rendering multipass standard vray buffer, I selected them in the vray settings and then select them on the multi-pass... button outsite the vray setting and select a path to render as targa files. And the only thing I get is a black image on all the passes except the rgba pass. or z depth.
Can you help me out, do you think im missing a step to render the passes?

[nycL45]

Upload a file that demonstrates the issues. Then, Tong will be able to/unable to duplicate it and to check your settings.

[theflu]

tong, did you redner your example in 1.2 or 1.3?

as for me, in 1.2 i get mostly crap out of the multipasses...seems to be kind of broken.
same scene brought to maya multipasses nice...

so i really hope this is redone in 1.3..

[froj]

I'd very much appreciate a quick PSD of any successful multipass setups or more detailed info if anyone has the time (Tong?). I've been looking around for the last day or so and tried some tests but I'm not having much luck.

My end goal is to composite vray animation into live footage so the multi-pass control is essential aswell as having perfect alpha/luma mattes to pull objects and leave reflection and shadows on the floor etc. This could be a linked or seperate issue but when I use matte's generated by Vray (including setting up white and black materials) I get a very fine halo around the object I'm trying to mask! I assume this is due to the lack of AA support for multipass.

Surprised something like this doesn't seem to be documented too well and I'm really struggling to figure out a half decent workflow. Any help or example files to dig through would be much appreciated.

Thanks Matt

[STRAT]

we're still waiting for a tutorial as to how to successfully multipass anf re-construct the image back in photoshop.

i know a lot of peeps says it can be done of course, but as of this post i'm still waiting to be told how :)

perhaps it isnt actually possible right now. i know Stefan's talked about a new re-vamped version coming out in vray 1.3 though

[stefan]

it should be very much possible.
there is no version 1.3 around, tong has done this in normal 1.2 or 1.2.5, (mp has not all featurs yet, but is not broken). i myself are no multipass user at all, not in ar and not vray so i cant help, but i know quite many vrayforc4rd users use it. it is only different than the c4d passes in the way to assemble as far i know.
tong will be so nice to upload the psd file soon i guess.

cheers
stefan

p.s the vray 1.3 will bring a new, expanded multipass system, with many more passes and much better AA control.(all passes from vray, which has a very well multipass systems in max version 1.5sp3)

[froj]

I think I have answered a few of my own questions in the last hour or so...

firstly I've pulled a perfect luma matte via materialID - I'd missed the checkbox to switch anti-aliasing on for this (in the anti-aliasing tab, obviously ha)

Also, I'm getting somewhere near now by removing the physical cam. I've heard it is possible but I can't figure out how - I either get super dark or super bright passes that bear no resemblance to what they should look like.
I've managed to use multiply (for raw light and GI) and add in after effects to get good results - not exactly the same as the rgb but with more control over the elements so that's good enough for me.

One odd thing I have noticed is that the raw light/GI seem to handle bump noise differently from their regular counterparts. Same size noise but different 'position' in the pattern. Has anyone experience this?

I'll continue to experiment thisafternoon and post my results in a zip for people to look at while we wait for Tong to post his results (please!).

ps. v1.3... are we talking weeks or months? Or is it too early in development to tell?

[miohn129]

Hi,

well I'm one of the users, how are crying (since the first VRay release)
for a good and funcional multipass workarround, because all of my renders
(still or animation) have to be finished in post!

With all my experiments so far, I cannot reproduce the rgba-image with separat passes.

So what I'm doing so far is:

- my base Layer in PSD is the rendered RGBA Image

- therefore I lower all specular- and glossy-effects in the scene
(because I can use the extra passes for reflection and spec
to pump up the amount - but I cannot lower it)

- I keep the rendering a bit darker ( because I can use GI- and Lightning Passes
to brighten up the image in PSD)

- I use pinhole camera for VRay rendering and render Alphas with AR


Thats the way I do it, but I hope, that 1.3 will solve all this
awkward workarround!
For example: With a normal multipass setup, it should be possible with a reflection-pass
to "raise up" or "lower" the reflecion or "completly remove" the whole refletcion.
This is impossible right now.

regards
mike
with one reflection-pass

[stefan]

i am very sure it is possible to make an rgba image,
your workflow is not the normal/intended one .

however 13 will have a nicer workflow for sure.
cheers
stefan

[miohn129]

Hi Stefan,

of course it is not the normal workflow.
Thats the reason why I'm posting this.

But, as the others already mentioned, no one has ever posted a
tutorial or way how to do it!

So I'm waiting for 1.3

thanks
Mike

[froj]

i am very sure it is possible to make an rgba image,
your workflow is not the normal/intended one .

however 13 will have a nicer workflow for sure.
cheers
stefan

Is there an estimated release date for 1.3?

Will there be physical camera support for the new multipass system?

Also, the shadow pass is always inverted... I read that its not a neccessary part of the RGB image in the same way as all the add operations are.. but for what I need eventually to composite the VRay elements over live footage (a photo would do for now!) then I need to isolate the shadow to multiply over the background.

[stefan]

as i said above the shadow part is inverted with intention-...a shadow is no added effect, but the absense of light....to my knowlegde you can do any withthe vray shadow pass, only the workflow is different as in old engines that add the shadow as extra effect.

cheers
stefan

p.s. 1.3 will be released when ready, i we keep here wit maxon. posting estimated dates only leads to rpoblems i learned....

----------

[leed]

even without AA i still havent found a tut that demonstrates how it all fits back together in photoshop 100% accurately. not even close. and without a system of rendering separate passes or layers and re-constructing them accurately in post then thats also a non starter.

Well not exact but..

Lee

[leed]

http://www.render.ru/images/uploads/Image/Tutor/max/405/Elements.jpg


(Background+Lighting+GlobalIllumination+Refraction +Specular+SelfIllumination)*AO+Reflection

"+" - Add,
"*" - Multiply.

;-) additional passes if you want you can use, AO pass can be made with 1.3 vrayc4d ;-) with 2side material and vray dirt shader ((( because it more correct way, then use override or luminance material

http://www.render.ru/images/uploads/Image/Tutor/max/405/AO_render_s.jpg

Tong

How do you get the Mt1ID layer to have those colours in it.. I mean more than 1 colour, as I can only get 1 colour.

Lee

[Tong]

http://clip2net.com/clip/m34722/1286467888-clip-70kb.jpg

http://clip2net.com/clip/m34722/1286467907-clip-104kb.jpg

[leed]

thanks..

Lee

[featherodd]

Is VrayC4D's multipass deficient or limited in comparison to Vray for 3DS? I haven't played with it much.

[STRAT]

couldn't answer that as i've not used both.

I can answer the fact that up until now (and on-going) nobodys yet demonstrated if how vrayforc4d's layered multipass render -> photoshop reconstruction is possible or even works. To be fair, close isn't good enough. professionally we need an exact science and working methodology