erickdt Posted November 20, 2009 Share Posted November 20, 2009 Even though I have enable fitering checked. This only seems to affect this file. Does anyone know what the issue that's causing this might be? E Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 Any ideas??? This is driving me up the wall. I cannot for the life of me understand why anybody would ever even want a non-filtered object ID pass. Why this is one of the only render elements that doesn't have filtering automatically checked is an absolute mystery to me... Link to comment Share on other sites More sharing options...
DanGrover Posted November 20, 2009 Share Posted November 20, 2009 Any ideas??? This is driving me up the wall. I cannot for the life of me understand why anybody would ever even want a non-filtered object ID pass. Why this is one of the only render elements that doesn't have filtering automatically checked is an absolute mystery to me... I suppose it could be for the same reason that it's a bad idea to have AA on a z-depth pass that you're using to drive a depth blur - that anti-aliasing essentially gives an "impure" colour. That is, in the case of a z-depth, a black object in front of a white one will end up with a slightly grey border after anti-aliasing, which mucks with the depth blur, as now there's an area of the image that's "between" the black and the white. I suppose the similar is true of colour ID's. Given it's purely a 2D process, you can't have AA turned on, or else the edge of a blue object over the top of a yellow one will give you a slightly green border, which of course wouldn't correspond to either objects in a comp. Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 Well, that makes sense to a point but you can easily account for that sort of issue by adjusting your magic wand/color range tolerance within Photoshop. If you're using an object ID pass as the basis for isolating objects in Photoshop a heavily aliased object ID pass doesn't do you much good. No? Anyway... Does anyone have any suggestion as to what's going on here and how I can fix it? Link to comment Share on other sites More sharing options...
DanGrover Posted November 20, 2009 Share Posted November 20, 2009 Well, that makes sense to a point but you can easily account for that sort of issue by adjusting your magic wand/color range tolerance within Photoshop. If you're using an object ID pass as the basis for isolating objects in Photoshop a heavily aliased object ID pass doesn't do you much good. No? I agree, it's a pain. I don't know the solution, though - after all, the pixels created as a result of the anti-aliasing could well end up being the same colour (or nearabouts) as another object id colour. Personally what I do is split the image up into a number of images which each only have 3 object IDs, one at 100% blue, one at 100% green and one at 100% red. This minimises the issue as it's very unlikely that any anti-aliasing you do will affect another object in the scene. This requires, I suspect, manual rendering rather than as a simple pass but I know a lot of people in the VFX industry who do it this way - though this may be because, at the time, their colour-picking tools were not quite as developed as Photoshops. Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 The thing that is the most wierd about this is that this issue appears to be specific only to this file/geometry (it also happens when I merge my scene into a new scene). I did the pulti-pass method on several renderings this past week with filtering enabled and it worked beautifully. I cannot for the life of me understand why it's not working now. E Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 So... you can strike my last post. I just opened the object ID pass from the other file that I was saying was anti-aliased and saw that it was in fact just as aliased as this new one it only seemed smoother becasue the resolution was much higher. So there you go: there is no way to properly anti-alias the object ID pass from VRay. To any Chaos group folks that might be listening: please fix this issue. E Link to comment Share on other sites More sharing options...
BrianKitts Posted November 20, 2009 Share Posted November 20, 2009 To any Chaos group folks that might be listening: please fix this issue. Not sure why you didn't just go to chaos group's forum with this, it's a known issue that's been discussed many times before. http://www.chaosgroup.com/forums/vbulletin/showthread.php?t=32211&highlight=antialias+render+elements Basic explanation is that the render ID's are expressed in integer values not floating point so they can not be filtered. However some of the other render elements are so they now have the option to be filtered. Basically Chaos has done what they can with the data that max creates, but can't do more. You'd be better to direct your request @ Autodesk, not chaosgroup. Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 I didn't post it in the chaos group forums because I'm not (yet) a member there. I'll let Autodesk know about my issue although I'm sure they've heard it before. What would be the best avenue for letting Autodesk know? A forum? Tech support? E Link to comment Share on other sites More sharing options...
Nic H Posted November 20, 2009 Share Posted November 20, 2009 you need to use multimatte instead Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 How do I assign different object IDs for mulitmatte? E Link to comment Share on other sites More sharing options...
Nic H Posted November 20, 2009 Share Posted November 20, 2009 right click and set object ID in object properties. Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 Hmmm. I've aleady done that for the objects I want to seperate out (as seen in the first screen shot I uploaded). When I use VRay Multimatte only one of those object shows up in the frame buffer (for multimatte) the rest is black. E Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 Okay... Figured it out. I had accidentally checked the MatID box and I haven't assigned any MatIDs within this file. So this only has the ability to make 3 masks? 1 red, 1 blue, 1 green? E Link to comment Share on other sites More sharing options...
erickdt Posted November 20, 2009 Author Share Posted November 20, 2009 So to make more than 3 masks you need to enable more than one instance of VRay MultiMatte within render elements and change the gbufID values to the corresponding object ID values that you want masks for. So if you need to mask out 6 things you enable multimatte twice in render elements, three times for 9 and so on. Not a perfect solution but better. This feature of VRay makes me think that they could do the same thing with unlimited ammounts of colors (for masks). That would certainly be a helpful tool. I'll suggest this over in the Chaos Group Forums. Thanks for everyone's help! E Link to comment Share on other sites More sharing options...
Stephen Thomas Posted November 20, 2009 Share Posted November 20, 2009 Once you do your 'select color range' in photoshop you can always do a 'refine edge' command to feather the selection according to your needs. Link to comment Share on other sites More sharing options...
WAcky Posted November 21, 2009 Share Posted November 21, 2009 no no no! The point of using a multi-matte element is so you can use the channels box in photoshop! Using select colour range and refine edge will never give you a perfect selection. Have your multimatte layer selected, go to you channels pallette and ctl+click one of the red green or blue channels and it will load the selection perfectly. Link to comment Share on other sites More sharing options...
Stephen Thomas Posted November 21, 2009 Share Posted November 21, 2009 no no no! The point of using a multi-matte element is so you can use the channels box in photoshop! Using select colour range and refine edge will never give you a perfect selection. Have your multimatte layer selected, go to you channels pallette and ctl+click one of the red green or blue channels and it will load the selection perfectly. Yeah sorry, I was referring to the Object ID pass rather than multimatte. Link to comment Share on other sites More sharing options...
kippu Posted November 21, 2009 Share Posted November 21, 2009 vray wire would also work with no setting up Link to comment Share on other sites More sharing options...
erickdt Posted December 9, 2009 Author Share Posted December 9, 2009 vray wire would also work with no setting up This is what I wound up doing. I actually very much prefer this method. It's really alot more versatile and more intuitive to setup IMO. Thanks! E Link to comment Share on other sites More sharing options...
WAcky Posted December 9, 2009 Share Posted December 9, 2009 But how do you get a perfect selection in photoshop? I've made a script that adds multimatteelements for you here. Link to comment Share on other sites More sharing options...
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