I got different result between viewport render and mantra render???wh

[CSN0309]

Hi~ guys

please have a look my attachments,,, looks like i got a different result between viewport render and mantra render why? i use Houdini 11(Education edition)....oh~ i have used my own shader inside SHOP...has anyone know where is this problem came from? thanks in advance

* oh~ one thing, i got a DOP network in my scene, when i delete the DOP network and do a viewport render, i got the wrong result(left one)!!!, but if i keep DOP in my scene, everything looks ok

Edited March 6, 2011 by CSN0309

[graham]

What rendering engine is your ROP set to? When using the render region tool if you have the Preview toggle enabled Mantra will use raytracing for primary samples even if your ROP is set to Micropolygon, which could possibly give you different results than a render through the node.

[LaidlawFX]

The viewport render region, and render view are modified version of the mantra render engine designed to render fast. While you can designate a mantra rop to provide parameter values for these views, some of the parameters are capped, or limited. There isn't a direct list of these parameters modifications that I am aware of though, to explain which settings are being effected. You shaders outputs may also be limited since they are directly tied to the render engine.

[rurik]

The viewport render region, and render view are modified version of the mantra render engine designed to render fast. While you can designate a mantra rop to provide parameter values for these views, some of the parameters are capped, or limited. There isn't a direct list of these parameters modifications that I am aware of though, to explain which settings are being effected. You shaders outputs may also be limited since they are directly tied to the render engine.

From what I remember hearing in a SideFx tutorial, the view Mantra render does not provide antialiasing...

Alex

[Macha]

From what I remember hearing in a SideFx tutorial, the view Mantra render does not provide antialiasing...

Alex

Hm? Where does it say that? It certainly looks antialiased. Or did you set sample filter to "closest" (for z depth for example)?

[rurik]

Hm? Where does it say that? It certainly looks antialiased. Or did you set sample filter to "closest" (for z depth for example)?

In one of the videos from the PyroFX tutorial series on the sideFx website

[CSN0309]

thanks guys~ i have changed the setting in Mantra render node as raytracing for primary samples, but problem still there~

[anim]

check your gamma correction in viewport and in render

maybe you need to show your correction toolbar for viewport (in persp1 menu)

[CSN0309]

ya~ i have changed the sample filter to "closest" ,,but problem still~~ i just simply put SSS and diffuse in my shader.. nothing big

[CSN0309]

oh~ one thing, i got DOP network in my scene, when i delete the DOP network and do a viewport render, i got the wrong result!!!, but if i keep DOP in my scene, everything looks ok

[LaidlawFX]

Hey, unless I am miss understanding, spend the time to make the mantra rop output that saves images look the way you want it. Don't try and make the viewport look better it is only designed for quick test, also you can't save images out of the renderviewport. It's always best to work for the output device your going to use whether it be mantra, renderman, air, or what ever.

I've had a very similar issue with animators before that they fall in love with the viewport image, and then they wonder why the "rendered" image doesn't look as "nice". If you do really want to match the viewport in your final render. Screen grab the image, crop it, and set it alongside your mantra rop render to your mplay window. And tweak the color, lights, and render settings.

Also deleting the dop network shouldn't change anything renderwise. You probably need to cache it out as a .bgeo sequence inside your sop network, so stuff doesn't change.

[CSN0309]

thanks guys, i got this problem solved.. change the Pixel Filter to "minmax min" and change sample filter to "closest surface" as well.....In nuke, change the color space to"linear"

Thanks!!! even through i still don't know why this happen..at least i can render my sequences, this is screenshot from my current project...

[CWest]

Not sure if this is obvious to most, but I found out that if you have headlight only lighting turned on for your viewport display, as apposed to normal lighting/high quality lighting, this will affect your render region.

So that might be another reason as to why peoples render regions look different to a mantra render, even if the render region is linked to the same mantra node.