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View Full Version : Vray render element with selected passes only!


fly2thesky
04-11-2009, 08:14 PM
Hi there,

I'm using Vray 1.50 Sp2 with render element. Can anyone tell me how to just render the selected passes only without re-render the whole scene? For instance, I just want to render the Reflection, GI, diffuse, lighting and Zdept only. No matter how I tried, it will still rendered the whole scene with the selected passes or with just the exr alone. This mean I do double works there!

I'm a licensed Vray user. I don't know whether I need the latest version of Vray 1.50 Sp3? If I do need, I can just download from Chaosgroup's website.

Last, I need to ask all the experts,

i) Do I still need to render with dirtmap or AO pass if I already have the Reflection, GI, diffuse, lighting passes?
ii) Do I need Velocity pass if my animation scene involved motion blur but without moving object?

Please help..... and thanks in advance!

Fly

fly2thesky
04-13-2009, 06:03 AM
http://i714.photobucket.com/albums/ww144/flytothesky_CG/VrayElementsmall.jpg
Download the tutorial here
(http://i714.photobucket.com/albums/ww144/flytothesky_CG/VrayElementdownload.jpg)

tecsun
04-17-2009, 06:43 AM
as far as I know, you have to re-render the scene because the element is extracted from the render. If there is any workaround to render only the reflection, I would love to know too.

1) Yes, you still need AO (well, if you find it useful then). Diffuse and reflection, etc are different from AO, which AO is use to enhance shadow thus make object seems more grounded and also bring back small details.

2) I'm not very sure in this but I had been using it last time and it does the job. Or maybe you can try apply motion blur filter and see whether it works.

Hope this help. :)

fly2thesky
04-22-2009, 03:24 AM
Hi Tecsun, thanks for your replied but I've asked Chaosgroup about it and they answered me the same. SO SAD! However I did a tutorial to help others about the "Vray Render Elements with Mental Ray Ambient Occlusion" above and hope this will help for those who needed. If you guys have similar tutorial to share, please post it too. Thanks!

as far as I know, you have to re-render the scene because the element is extracted from the render. If there is any workaround to render only the reflection, I would love to know too.

1) Yes, you still need AO (well, if you find it useful then). Diffuse and reflection, etc are different from AO, which AO is use to enhance shadow thus make object seems more grounded and also bring back small details.

2) I'm not very sure in this but I had been using it last time and it does the job. Or maybe you can try apply motion blur filter and see whether it works.

Hope this help. :)

tecsun
04-28-2009, 01:48 AM
thanks for sharing the tutorial.

yupe, I felt the same last time, but then I find that Mental ray also need to re-render the scene before you can get the element, isn't it? Or there is some way to get it done in MR?

When I was doing my demoreel last time, I never use vray for all the purpose. for example z-depth takes damn long to render with vray, but with scanline it is incredibly fast. And also realize that vray tends to render slower with GI turned off, weird :surprised

btw, may I know what's the purpose of having the 50% unclamped color? Have you try render VrayDirt with Image sampler type set to Adaptive Subdivision (or Fixed)? I think that will render faster as well as less grainy.

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04-28-2009, 01:48 AM
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