jumper Posted July 15, 2011 Share Posted July 15, 2011 Hey, I am trying to use mantra's Pz pass with depth slicing. The first image is the beauty - (with a lot of gain) to show the sub-pixels The second is the pz pass. I need to get the pz to cover All the sub-pixels of the beauty to get the depth slicing to work. I have tried "Sample Filter" set to "Closest Surface" and I have tried various "Pixel Filter" settings.... eg "Closest Sample Filtering" - "minmax min", but the pz pass doesn't cover all the sub-pixels from the beauty. Would appreciate it if someone has any ideas? I have attached a simple hip. Like I said sidefx_pz_v002.0001.jpg is the beauty with a lot of gain added to highlight the issue. Both images are cropped - close-ups of a feature of the render. Thanks in advance! Stephen edges_v001.hip 1 Quote Link to comment Share on other sites More sharing options...
rob Posted July 16, 2011 Share Posted July 16, 2011 The beauty is pre multiplied If you divide by alpha in Nuke the pz pass should be correct. r Quote Link to comment Share on other sites More sharing options...
jumper Posted July 18, 2011 Author Share Posted July 18, 2011 The beauty is pre multiplied If you divide by alpha in Nuke the pz pass should be correct. r Hey, Thanks for the reply but this is not a pre-mult problem. if you look at the alpha of the beauty itself there are pixels oustide the Pz render.. I need the Pz to cover ALL the pixels in the alpha but without anti-aliasing. Thanks s Quote Link to comment Share on other sites More sharing options...
Fabiano Berlim Posted July 18, 2011 Share Posted July 18, 2011 I need the Pz to cover ALL the pixels in the alpha but without anti-aliasing. If you really need to be that precise, you must to use the same filter. So, if you're using default "gaussian 2 2" to C plane, you need to use "gaussian 2 2" in Pz plane. Of course you're going to have a problem with premult Pz. So, in comp, you need to divide Pz plane by the alpha (unpremult). This will bring back the correct value of Pz plane. I'm attaching an example file. Just go to composite view and check both channels. filter.hip Quote Link to comment Share on other sites More sharing options...
Stalkerx777 Posted October 31, 2011 Share Posted October 31, 2011 Hi. I'm having a little problem with opacity filtering in Pz pass. Take a look please, what's wrong here. Color Pz - trace engine Pz - micropoligon engine Scene: opacity_filtering.hip Quote Link to comment Share on other sites More sharing options...
gaurav Posted October 31, 2011 Share Posted October 31, 2011 One solution could be rendering out a separate pass for it where Pz is multiplied with alpha only for the star mapped plane. But lets see how pros do it. Cheers!! opacity_filtering_01.hipnc Quote Link to comment Share on other sites More sharing options...
Stalkerx777 Posted October 31, 2011 Share Posted October 31, 2011 One solution could be rendering out a separate pass for it where Pz is multiplied with alpha only for the star mapped plane. Yes, in case this very simple scene it would be ok, but i have a complex scene with a lot of semi transparent objects. I thought that opacity filtering could handle this properly, but it seams not. In raytrace engine it's seams to accumulate z value in transparent areas. But more interesting in whats happening in micropoly engine. Its just making holes, regardless whether filtering set to closest surface or opacity . And to eliminate them, i had to increase shading rate!! Very strange. Any idea? Quote Link to comment Share on other sites More sharing options...
Fabiano Berlim Posted November 1, 2011 Share Posted November 1, 2011 You can turn on raytracing shading in the shading parameter of the object. Not a great solution but it works. Quote Link to comment Share on other sites More sharing options...
Stalkerx777 Posted November 1, 2011 Share Posted November 1, 2011 You can turn on raytracing shading in the shading parameter of the object. Not a great solution but it works. Yes,i can, but i don't need raytracing in scene. And even in raytrace shading, Pz values "accumulates". I'm more interesting why i need to drastically increase shading rate to get what i need. Anyway,thx for reply, i think i'll cross post it on sesi forum. Quote Link to comment Share on other sites More sharing options...
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