Maya 2017 - Render Layers in Arnold

hello and welcome to another exciting tutorial in Maya 2017 where today we're going to be talking all about rendering now it's important that we're going to be using Arnold as our main renderer today and of leaving you guys a scene that to set up I'm going to go over here and choose set project and I'm going to select the render layers projects folder which I'll leave available for you guys on Google Drive if you want to download it check out the show notes below and then I'm going to open up one of my scenes over here which you'll have available to you which is render layers version one I'm going to hit don't save to this and let's open up this file over here so it's a very simple scene of just some basic objects one of them which has so check the textures that we made in a previous tutorial the bottle makes a little reparent as well I've got three little spheres inside here as well so the subject of today is talking all about rendering and this scene I've already kind of like set up for you guys to an extent you can see that actually I have kind of like my scene lit up over here if I change the gamma to 2.2 this might depend a little bit on the monitor that you're using but specifically for my laptop it seems to allow me to see the colors much better if you see an image that looks similar to this just leave the settings as they are right now so importantly for us what I'm going to be doing today is that we've been so far rendering images out and all of the images have been exactly the same in terms of we've been rendering out a final image that we've actually not been using for color correction or moving into another application or using it for the effects on or anything we've kind of like just been focusing on creating one final good image so I've actually gone through and giving you just a few settings here which work kind of well and you know I've worked out some of the problems with kind of like how many samples the lights had to have how many passes is the diffuse needed to have in order to reduce a little bit of the noise and all this other fun technical stuff as well because today what I want to talk to you guys about is rendering out your images by using either what Arnold calls a OVS which is arbitrary output values which we traditionally would have actually called I believe render passes per se if I'm correct and then there also is the render layers themselves or some people call them render elements as well and very much disregard of whatever you call these things very much there's two ways of thinking about what we're rendering with Arnold's alvie's or render passes you prefer to call them that way is the fact that what we're rendering out actually is already made as part of the components of what the image actually is so things like if you're looking for a diffuse pass or you're looking for specular information all of this type of stuff here is computed by Arnold at this point in time to create the final image so it doesn't increase your render time you're looking at Arnold splitting up this image into various parts and understanding that you're using kind of like different elements to build up this final image while as when we're thinking about in Arnold about render layers specifically or render elements if you call them like that it's about either selecting certain objects and rendering them in isolation or doing like an ambient occlusion pass or you know you're effectively having to re render the image to actually create that specific effect per se so what I'm going to be doing today is that I'm going to show you guys how to set up some AOV is to allow you to have control over rendering out the diffuse the specular and the refractive nurse kind of like all separately there are little passes and then what I'm going to do is go ahead and show you how to use the new render editor over here which we've got this render setup window over here that takes over from the render layers which used to be traditionally inside of Maya inside of the channel editor a channel box editor now for whatever reason you don't like this system in whatever way that you don't want to actually use it because you're much more comfortable with the old render settings in Maya 2017 the old render settings still do exist so don't worry those haven't gone anywhere but you have to go into your preferences over here we're just going to click on the icon over here and inside the Maya preferences tab over here if I go into rendering over here you'll see that the preferred render setup system is currently set to render setup that Arnold's render setup window if you want to use Maya's traditional render layers again as I said before everything's changing names to an extent but it still pretty much works with the same philosophy in mind as well so importantly here we've got ourselves that if we want to use the older inner layer system we can do that and we'd have to restart my but for today all I'm going to do start working out with this image over here so this tutorial is going to focus very much on the idea of rendering out with the purpose of compositing or color correcting if you know a little bit of nuke this will be fantastic for you but even if you know a little bit of photoshop there's a lot of editing that we can do with our render passes and render layers and that will be absolutely great for us to be able to do small little changes to our images without having to go back and re render our entire thing so let's start off first of all with what do we have in the AO v's so if I open up my render settings over here one of the things that's important for us to start rendering before we do anything is to make sure that our settings are set correctly now I've got an e XR setup by default as my 2017 comes in like that you might have to change that to another file if necessary all of the image that I'm going to rent today are going to be opening xrs and then you know you choose what you want to render out if you want a single frame you choose of course name extension single frame name number extension would be great if I was doing animation of any sort but I'm going to leave it to a single frame just to keep this tutorial very very very very short and again I need to choose what is my renderable camera so I'm going to make sure that that is shot cam and then inside here I'm going to leave it at a low-end HD over here so it will my previews don't take too long because the bigger the size of the image the longer the image will take to render per se and later on I might render out for the final thing just at a slightly higher resolution later on okay so inside these tabs we've played around a lot with the Arnold render up but there is this section over here which is called a Ovie's now this again some people might call them render passes are actually the elements which exist and this is very closely connected in Arnold with the shaders themselves if you notice over here there's a whole series of groups and I have over here my Arnold standard material and the effects that I could possibly render out from this type of material now I've made the scene so that everything has got the Arnold standard material so this is all of them you can see how flexible that actually is but I'm interested in editing certain properties and those properties will be the diffuse which can be direct or indirect and the specular so the actual highlights per se and the indirect specular as well and then I'm going to render out the refraction but for this specific example I didn't use any true reflections as well so if you actually render out the reflection pass here you're going to get a black screen completely because there isn't any inside of this scene so effectively you're just choosing the elements that you actually want to be able to edit if I had any glowing material so I could choose an emission property over here it's important when rendering that you only render out the materials that you need so this scene only has direct diffuse indirect specular and it also only has indirect diffuse and indirect specular and it only has fraction like that as well okay so those are the four main five a Ovie's that I am going to render out and to add them to my renderer all I need to do is press this kind of light double line button over here and you'll see that it adds them into this list down here now currently it's going to render out all of these different passes they're all going to be RGB types of data over here so they'll have either a no alpha chat panel embedded into them and I could also choose to change the file type that they're being rendered to if I didn't want to work with the Exile but I wanted to rent it to tip 4 to JPEG I can change them automatically here and I'm already customizing what this image is going to look like when I press the render button at the end and render out all of my different passes automatically so now that this is set up I can still preview what this image actually looks like so if I come over here and I press the interactive renderer over here and turn this on I might have to just reload this because I think not there are all my arrow V's fortunately if you don't see this list here sometimes you have to close the panel down and open it up again but if I went into the direct diffuse channel over here you'll see that the image that I get is ever so slightly different you'll see that I can see the texture of the box because that's the diffuse color of it and you'll also see that I can see the gray sphere over here inside over here but you'll notice that this material over here which is a chrome sphere that I made with the Arnold standard material and a glass sphere over here with the glass bottle over here on the left-hand side you'll see that all of those materials that have either high reflectivity or high reflectivity actually are black in the diffuse channel and that's because inside of their own materials okay so if I select it say for example this sphere over here and I right clicked on it and I went to material attributes just to bring it up there for a second what you're going to see is that I have over here oops if I choose the again chrome material over here you'll see that the diffuse color is actually set to black so you'll see that that's the color will appear in the direct diffuse Channel now what do the other channels do the fun thing about this process is that Maya is still rendering wait the whole image while it's going through the a Ovie's so if I go over here to the direct specular channel over here you see I just see the actual effects of the highlights of the lights which are inside of my scene I've made three lights for you they're an orange one a blue one and a white one on top and if I go over here to the indirect diffuse which is what I wanted to click on originally you're going to see that there is a lot of indirect lighting being casted here if I wanted to play around with that color bleed property that we've used before in our interior lighting tutorial you see that this is a way that I can actually take this image and I can actually boost that effect if I wanted to you'll see that the image is a little bit noisy over here and if I added more bounce lights over here I could actually start clearing this up as well AO views are a great way of understanding where you need to be increasing certain properties inside of the render settings so inside the render settings inside of the Arnold renderer we do have the diffuse samples over here and we also have the diffuse rays as well and the more rays and more samples we get the smoother the diffuse is going to become so I might have to boost up these properties later on for actually getting a nice smooth render over here but this is a great way of debugging this type of stuff so I'll keep leaving this image kind of like rendering out over here and we'll go into the indirect specular and see what we can see there and you'll notice that here what we see is actually the reflections from the environment you can see actually here the ground plane and a few other details on the chrome sphere very clearly like that and last but not least we've got this refraction pass over here which is really going to focus down on what this sphere and the inside of this bottle actually look like as well and the big advantage of all of this is that all of these passes kind of like when slapped together and composed in the right way will make the beauty pass so this will still take the same time to render but it's going to create all of these separate layers for us which we can open up in Photoshop so the last thing that I want to point out specifically about this if I go into any one of the channels like the refraction channel over here you'll see that this image actually is kind of like completely black and has a little bit of color but if I press this button over here and I go through the actual channels over here red green and blue you'll see that when I get to the Alpha Channel you're going to notice that all of this is white so it does mean that all of these pixels which are being rendered are not on a transparency don't think that that black is going to be transparent this color actually is going to be black pixels and we'll have to use some layer blending modes later on in order to make this over here so all of this stuff has been rendered out nice and good over there and what I'm going to do next is before I even play around with any of these settings I'm going to introduce you guys to a new tool set ok so inside a Maya 20 2017 you've got this little button up here which is like a little checkered pattern sorry a little clapper board with some layers on it in the bottom right hand corner you can go into Windows rendering editor and choose the new render setup window over here and that will open this up over here now this will make what traditionally was the Maya render layers and in my 2017 we've got a new interface and a new way of working with this and to make this just a little bit clearer for us what I'm going to do is that I'm going to open my panels up into two like this and what I'm going to do is just add into this side panel over here my outliner so I can see all of the objects inside of my scene I'm going to go to panels panel outliner over there and again the outliner is the scene list effectively all of my objects which are inside of my scene or inside they're just so that I can have these here so the way that this works is that this render layers window is going to allow me to actually customize what is being rendered that every time I use it it's going to add something to the render so it means that it will have to do calculations twice so anything that I add here will increment my render time by just a little bit depending on what I'm actually rendering out it's still very very very useful but what we're going to do is I'm going to start off by creating a new render layer and I'm going to render a specific effect that's called ambient occlusion I'm going to come over here and I'm going to open this layers panel over here and the render layers a system inside of Maya 2017 really forces you to be organized I've got a layer over here and I'm going to call this a Oh for ambient occlusion just so that I make that mental note over here and the way that this works inside of Maya 2017 is that this render layer system will also influence what we see in the viewport as well if I come over here it works by creating certain things which are called collections which if I right click on that layer menu and go to create collection it's going to create something that's called a collection in here and this is like a group of objects I'm going to call this geometry over here and actually if I type in geometry a correctly it works even better geomet now I did spell that correct I think again always being kind of like a bit doubtful with my spelling per se I think a lot of creative people get that as well so this ambient occlusion now needs to be applied to specific objects inside of my scene and in my 2017 they make you put all of your objects into an actual collection like this now this collection specifically I can add objects to it by just grabbing them effectively from this outliner and I can just middle mouse button click and drag and add objects into my collection like this so I've just added the crate object into my collection if I activate the render layer by pressing this I drop tool you'll see that in the viewport it will show me the objects which are inside of this render layer and effectively hide all of the other objects which are inside here so when I press this I dropped all its share this I tool is showing me what is inside my collection over here now there is a whole other series of ways of adding things to it and people can think of oh it's going to be a lot of hassle to kind of like just grab all of these objects and put them here but here's where if you are diligent with how you name the objects inside of your scene it can be really really really easy to do this now there's a few tutorials that show you more about how to do this I'm going to show you very easy way because in my scene all of the objects that are geometry I've called geo and what I'm going to do is go into this area over here which says create expression at the top and I can type the names of certain objects with a little script that will allow me to select it faster so one of the things that I've done is that if I type in geo and I add an asterisk behind it over here it will select every object in the outliner in my scene that starts with the word geo so if I press select over there you'll see that everything that has geo written over here is actually going to actually highlight and if I push this Add button over here it's going to add all of those objects into my render layer and hey presto here they all are in my viewport okay so if you've named everything in here it's very easy to bring in all your geometry bring in all of your lights but what happens over here with this guy over here which I've left kind of like purposefully not named with Gio at the end of it I could start by actually typing in BG if I wanted to but what happens if I missed an object and I need to rename it later on it doesn't matter I can just come into here type in Gio at the start over there like that go back into here and you'll notice that this script is already running and again I've just renamed that and it's automatically brought in the background a little plane that I made over here as soon as I renamed it because this little script is active over here so it's really really really useful as soon as I rename an object then it has Gio in front of it it will automatically be added into this collection so the new layer system is very very very smart but it does force you to be a little bit more organized if you want to use it or again you can just drag and drop things in here as well if you've got very simple scenes this is a complete piece of cake so what are we going to do with this render layer now it has all of the geometry in my scene I haven't used any of my lights or any other fancy things that I could do in here as well what I can do is that I can right click here and I've got some more options over here with what I can do with the render layer and what I want to use is use a tool which is called create material override what this is going to do is that currently my scene has lots and lots and lots and lots of different textures over here and I want to apply a new texture called ambient occlusion over the top of my entire scene without destroying the previous texture work that I've done which is why I'm making a render layer so this material override I'm just going to rename it to material override AO for ambient occlusion over here and then I can choose a texture inside of this override material and if press this little check button over here it will bring up my traditional create render node section over here so what I'm going to do is type in AI because I'm looking for an Arnold shader and there is an Arnold ambient occlusion shader over here which is really cool so I just press that there and you'll see that in my viewport everything kind of like changes to gray like this and again I've got my render layer active so when I go into the Arnold render view again I hopefully should see the effects of the ambient occlusion if I go into the beauty layer over here and this is what ambient occlusion actually looks like it's a black and white texture that fills in the entire scene it's really really really useful for creating contact shadows and kind of like highlighting like the dark edges of this box over here as well and there's a load of interesting settings that we can play around with as well I'm just going to hide the render layers for just a minute if you see here in my attribute editor I've got ambient occlusion and the great thing about Arnold is that with the interactive renderer I can actually play around with the settings if i zoom into this image I might notice that there actually is some noise inside of this immune occlusion so I can increase the shape of the samples to 5 and Arnold will rerender what this looks like if I play around with this spread property over here you'll see that I can increase the contrast of my ambient occlusion as well so I can make these contact shadow areas look darker like that so again I'm just going to give it like a little value of just a little bit more contrast of about 0.8 over here and then if I want to play around with properties like the near clip and far clip per se if I just zoom out of this for just one second over here what I'm going to do is just come into this far clip and if I increase it you can see that it starts filling in a little bit of gray around the background over here so I can actually start seeing the curve of my background plane inside of there so I'm going to come over here and actually I don't really want to see that per se so I'm going to take whoops not the spread but the far clip I'm just going to bring it down to of how you of about 100 maybe a little bit less than up that's too much there we go I'm going to do it there for about 120 seems like a good number there we go okay and if I wanted to do any other changes I could do that as well and colorize it as I want but that's kind of like the effect that I'm actually looking for so I'm quite happy with that ambient occlusion powers again this is possible thanks to the render layer system inside of Maya which again if I open it up very briefly and I just turn off this render layer I have not destroyed any of my work what happens is I can hopefully just come into here and hopefully if I can just hit this icon over here this little eyedropper tool just having a little bit of trouble with my graphics tablet there for it to actually engage in the right place you can see that I have my Beauty pass all ready done and everything looks absolutely great just like that so again this is a very easy way of replacing all of the textures inside of my image with a different texture like an ambient occlusion pass so you're going to see that this ambient occlusion pass only took 13 seconds to render which is not really you know a lot in terms of how long a render could actually take but it's going to be some extra seconds that we're going to add on to our overall render time another thing that's quite useful to render out as well especially for presenting your 3d work is a wireframe pass as well because people who see your 3d work especially employers are always interested in how you've modeled your actual scenes as well so if you've got a demo reel or something it's always good to add breakdowns and little video clips that actually explain how you put the image together and wireframes are really really really useful so inside the render setup window again I'm going to create a new layer so I'm going to come into here and I'm going to select this little layer over here just going to close down my render editor to an extent and this new layer I'm going to call wire frame just like that and then again I'm going to do the same thing one more time I'm going to come over here I'm going to create another collection over here this collection again I'm going to call it geo as well for geometry and I'm going to come into here and I'm going to use the same script that I did before which is geo ok sensitive and put a little star in there hit select and then just add them into my list like that so I've already got all of my geometry bang slammed in there as well again with the wireframe I'm not really going to worry about the lights because the material overrides that I'm going to use won't require me to have lights specifically so if I came over here and selected this and I went into let's say for example bum bum bum bum bum create material override again this material override is going to be wireframe over there and I'm going to look for a specific Arnold shader again so I'm going to click on the check pattern over here I'm going to type in AI W for AI wireframe here and you'll see that this AI wireframe node over here has some properties inside of it as well and the good thing about this one you could use an Arnold utility material to do something very similar as well but this one actually allows you to customize what the image actually looks like so if I came over here into my Arnold render view over here and I made sure that I switch from the ambient occlusion layer to be turned on to turn on the wireframe layer over here you'll see that this looks a little bit weird because all my faces are triangulated like that what I'm going to do oops I just split off the window like that and actually I can just hopefully redock it like so again new my 2017 windows that you can just pull apart by accident just like that if I turn this to polygon so you're going to see that now I've actually got the shape of each polygon face which is going to be much more important if I was going to use multiply and have dark lines over my objects over here I'd probably leave it like this but just do something a little bit cooler later on what I'm going to do is that I'm actually going to change the background color black here and I'm going to take my line color and I'm going to use something like a bright slightly brighter scientist color like they're like 50% cyan over there just so that it looks a little bit like Tron or kind of like one of those old 80s computer movies as well where everything had the wireframes actually highlighted so there we go we've got ourselves our second set of render layers over here which again is going to be good for presentations as well and you're going to see again five seconds to render that that's again still very very very very very useful to us as well as we move forward we're going to have to start making some other things inside of here currently I'm only using the render layers for creating things that I actually kind of like want to render as a final image but this system is amazingly powerful as well you can make a layers for your lights and you know just change the intensity for them as well and you can do loads of other fun little things as well now going to take a moment to start making a material ID node now this is really useful for when you're doing kind of like quite complicated compositing and it's really useful for people who use nuke or people who use After Effects because it allows us to create a specific mask that we can select thanks to a color so that we can have very finite control over the objects inside of our scene well later on be creating a mask traditional kind of like Photoshop style alpha channel as well that we can render out and again this will allow us to have some customizable controls inside of whichever image editing software that we want to use but if you're specifically looking for how to create material IDs inside of Arnold this is a great way of actually doing it and I'm not even sure if it's the only way of doing it probably there's other ways as well so let me know if you know any other techniques down below in the comments that would be great so what I'm going to do is I'm just going to close down my render editor for one second but before I do that I want to actually cut back to my Beauty pass so I'm just going to make sure that my render layers are actually turned off like that just so that I've got the actual image over here now to create material IDs inside of our own what I'm going to do is I'm going to be playing around with these three spheres I could choose any other combination of objects that I would want to as well inside of my scene but I'm just going to leave you the most simplest ones to actually work with so it's quite quite effective if I select this sphere over here and right-click on it and go in the list down to material attributes and wait for those to load up inside of my actual attribute editor you're going to see that I'm going to be have made a sphere with a color of like 0.15 over here I'm just going to copy that value to an extent but I'll hopefully remember it as well three digits oh my god what I'm going to do is I'm going to add a new material into the diffuse color over here I'm going to do that by clicking on the check pattern over here and I'm going to look might have to click in the Arnold section over here for an attribute that is called AIW Arnold right color okay so this right color material over here is going to have two properties beauty and input over here and the beauty pass over here is actually going to be the same color as I had before 0.15 over here if it's a color that I have selected you know like the gray sphere over here if I had a texture I would have to connect it into here again and I could do that in the hypershade or just through the nodes inside of the attribute editor if I wanted to so the beauty has to be the same color as the diffuse color that we originally had and then the input we're going to plug in an Arnold utility material so I'm going to go into a IU if it doesn't appear I'll just click on Arnold to filter that down to actually be my Arnold utility node I'm going to click on that there and the orange utility I'm going to change its shaded mode to flat so it's a completely flat color and then what I'm going to do is select red as that primary color over there and that's going to be the start of making my material ID only thing I need to do now is to create a custom a V again an arbitrary output value what I'm going to do is just go up a level by clicking on this button over here or I could go back to the material selection and work my way down the tree if necessary and inside here I've got this name property in right color attributes so if I click on this here you'll see that I've got various channels that I can contribute it to those are my a OVS and at the bottom I've got an option that's called create new I'm going to click create new and it will ask me to specify a name for my Iove and Arnold does a really good job at allowing you to create custom a RVs for loads of different effects so if I come over here I'm just going to call this object ID all together like that and hit create hopefully the name up here should update to object ID and if I go into the render settings by pressing the little clapperboard with the gear box over here and I go into my Iove I should see that I've got a property over here which is now called object I D okay so with that all set up when I go into my Arnold render view again I should have a new pass inside of my list which is called object ID and if I click on it you'll see it's a red sphere like this now the advantage of this is specifically if I go into the channels over here and I click through this you're going to see that this material ID actually has in its Alpha Channel a little mask like this okay so white and black pixels anything that's white is going to be solid pixels anything that's black is going to be transparent and Gray's would be kind of like the transition in between them over here so importantly this allows me to actually select parts of my image thanks to this color with its own little alpha channel over here as well you'll also notice that inside here the object ID is an RGB a type of thing saying it's got red green blue colors and it has an alpha Channel so the great thing about this is that programs like nuke or After Effects allow you to select specific colors we're going to pull that rental hair setting out from there it just docked again into my screen that's going to allow me to basically take or air these specific materials and if I wanted to adjust like their color or their contrast I can use those individual color IDs to rapidly select them inside of my compositing program and I can tweak their values specifically just for that object we could render out a whole series of these again but again just so that you get the idea of how this works I'm going to make one for the mid gray sphere one for the chrome sphere and another one for the glass sphere and what I'm going to do is select this one over here right click again do the same thing and I'll come over and I'll choose my material attributes over here and inside not mid gray over here just still click on that again over here so you can I have my chrome sphere might be because I've got my render layers turned on that's something that happens as well so good that I've kind of like bumped into that no that's not on there I thought that I had some form of override maybe happening over here I'll just go over here back to my render view is it because I'm in my object ID I'm just going to close that down close that down right click on this here not in face mode I might be because of instance these over here there we go I can see my chrome tab over here and there we go I actually have my chrome material over here I can click on here to do it or if I'm having specific trouble finding a specific texture again just open the hypershade and you'll be able to see that if I come over here and open up my chrome material which is this one over here and I just map that into my scene like that and just come over here and do the same thing and the hypershade it's pretty much the same thing typing AIW to look for an Arnold right to color node come in here the chrome material doesn't have a color in its beauty parser that can remain in black in the input over here I am going to connect an Arnold utility material and I'm going to click that there and I'm going to make the second color green and the third color I'll make the other material will be blue so I'm going to come into here make sure that that is 100% green come over here choose flat over there and I've got my flat material ID like that now the great thing about this as well is that if I come into micro material and I map that so I can show you guys all of the texture nodes inside of here I'm just going to give myself a little bit more real estate by making my window a little bit bigger like that you're going to see that what I've effectively done is that I have created a Arnold standard material inside the diffuse color I've plugged in this right to color node which allows me to have a beauty input and also to have an input over here for a specific a avi and inside here when I'm selecting this again I can choose to which a ovie is this going to be applied to and I'm going to choose object ID like that doesn't look like it's made any changes inside of here but when I go into Arnold interview and I bring up my object ID you're going to see that now I have a red sphere and I have a green sphere as well now as I mentioned before these IDs are really really really useful for high and compositing but it's one of those things that you might need or you might not need depending on which other programs you're going to be using so I've gone along ahead and just to save you a little bit of repetitiveness I've gone and I've created a blue material ID as well and I think specifically for nuke people are always very interested in using red green and blues like those primary colors for screen and you can create multiple kind of like images with loads of different selections based on what you want to have kind of like that finite control over I have also seen other people use other colors as well like scions yellows pinks and stuff like that you should be able to select a color as well but the really important thing about this technique is that you see that I can select the different colors and use each one of those as a alpha Channel or all three of them together actually are an alpha channel in and of themselves you'll see how that applies later on when we go into Photoshop but Photoshop specifically would want to use a much easier type of alpha channel for creating kind of like transparencies of for different objects and Arnold does this as well in a very easy and fun way as well which is actually it creates a opacity map effectively which will be a black and white image which we can use as we can use masks inside of Photoshop so to set up this paths again I'm going to use the best of both worlds right now where I'm going again to create another collection inside of my render layers so I'm going to open the layer set up other render setup panel again over here I'm going to make myself a new render set up over here and this one I'm going to call it alpha 4 Alpha Channel effectively and again just going to make sure that that's lowercase there we go I'm going to then create a collection as we did before this is also going to be geo except that this geo over here is going to be everything except my background plane so instead of using the script I'm just going to right-click over here on the 5 pieces of geometry throw that in there turn on my visibility over here so I can actually see what the Alpha Channel is actually doing over here and if I turn that on there we go so I now have all of the objects like that selected in my scene over here and I'm not really going to do a material override on this I'm just going to leave it the way it is and if you wanted to you could render this out as an axr and everything behind crates would be transparent as well there's many ways of building up these images and you know as you get more into kind of like what you want to edit you get a little bit more specific about oh you know I want to render out these specific elements separately or other stuff like that so I'm basically using around a layer right now to choose the objects which I'm actually going to be rendering out over here and then what I'm going to do is I create a new a OFI as well so I'm going to come into the render settings over here and asides from the UVs that are available for the Arnold standard material we also have this one at the top which is a built in material as well you'll see that IDs is something that we can configure inside of here as well there also is a he normals pass there also is a z-depth pass which people like using for depth of field you do need to have the you need you do need to use nuke in order to make this work straight out of the box but down here again there should be an alphabetical order there is an app a city map inside of here if I add this into my list over here like that this will again add it to the active a Ovie's over here so hopefully that should appear in my list some point and the other thing that we can play around with have a look let me just close that and refresh it for a second I'm over my pasty hopefully should be in the active list I can't see it down out there is opacity now you'll see it also is an RGB type of object inside of there okay now specifically if I take any of these built-in objects they tend to be things that you can't see inside of the image so for example if I choose the Z for Z depth and I added that into my scene over here you'll see that this Z depth object over here it's actually not an RGB image but it actually is a float based value instead it's the way that the camera could measure distances of the objects from the nearest object to the camera to the farthest object in the camera and nuke does a really good job at actually just creating a Z depth file from this file with no problems whatsoever but again I'm not going to render it out because it would just be like a solid red type of image if I let open it up in Photoshop so I'm just going to unload that and these are all the passes that I'm going to use so I've got some render layers I've got myself some a OVS as well and now I can start thinking about rendering out the final version of that image which is hopefully everything all together so let's go about rendering out this entire scene and to do that what I'm going to do is that I'm going to switch from the modeling toolkit to the rendering toolkit over here and that will change the options available for me in the top menu up here inside the render traditionally we've always used the batch render control but now for Arnold we've got this render sequence tool inside here and what I'm going to do is press this button over here to open up the advanced features inside of here and you're going to see that one of the things that I want tick on is to have all of my layers actually rendered over here and again importantly this render sequence by default will follow the settings that are inside of this common tab over here again the file format again making sure that I'm rendering out a single frame with a name and an extension number behind it as well if I wanted to now though I could change it to any other resolution that I could be working to 720 580 all of the HD formats that it could be could be using so I'm going to either choose HD 720 or choose 1080 over here and again it will show me how image the size and pixels is don't try to render things that are you know amazingly large and then just you know reduce them in whatever program you want try to render out you know a setting that is either good for YouTube or for other things and so I'm just going to render it out at 720 because that's what my videos are currently going out of until kind of like I have a little bit of time to play around with Camtasia and I see if I can actually get into 1080 at least so what I'm going to do so I've just skipped ahead a little bit and I've rendered out all of my scenes and if I open them up inside of my viewer over here you'll see that I'm rendering out all these different folders over here specifically my master layer will contain all of my UVs my then specific render layers will be contained in the Alpha the AO and the wire and currently I've made kind of like a few more folders than I actually needed all the information for the different files will actually be inside of the beauty folder over here so if I'm looking for the ambient occlusion the alpha or the wireframe I'll do that but make sure your rendering from the correct shop cam as well I had to put my viewport in Maya to actually have my camera in view to render it out so just be careful with that in case it snags you up and I also made a little mistake with the Alpha as well where when I rented it out I actually rendered out an individual EXR as well which if I just open that up in Photoshop it will ask me if I want to render this out as a transparency or as an alpha channel and actually I'm going to choose to open this specific one as an alpha channel I could do transparency on all the other ones because I actually made a colored version of this and if I open up my alpha channel over here you'll see that actually this was the image that I actually wanted to create so there's a little mistake on my behalf because I've basically made you know my alpha channel is there but I actually rendered out an RGB version of it as well so I'll take this and I'll press ctrl-a on my keyboard or Apple a to select everything and then press ctrl a ctrl C and inside of my layers panel here I'll just paste in this alpha channel just in case I need it later on and I'll come over here I'll just call this alpha just like that okay so now I've got quite a few layers inside of my scene like this all renamed over here and all of these layers over here should allow me to edit my as I see fit per se so importantly if I turn on the bottom layer over here and I'm looking at the diffuse direct light over here as well you'll see that there's no color inside of these areas over here and then if I've got my indirect diffuse pass over here you'll see that what happens is that if I change this to another blending mode I can actually start recreating what the original beauty pass actually looked like but I can choose to modify things ever so slightly one thing that I'm going to do with this file as well is that you'll see that when you open up an EXR and my specific version of Photoshop you'll see that there actually has kind of like some of the layer blending modes turned off so what I'm actually going to do is I'm going to reduce the resolution of the image colors by going into mode and changing it from a 32-bit image to a 16-bit I'll choose not to merge any of this so that all of my layers are the same and it will just run through all of this and re kind of like colorize all of my layers but now I'll have full access to all of these settings over here as well if you're working in Nuuk you won't have a problem like this at all so what I'm going to do is that in the end direct diffuse I need to choose how these things are going to start mixing and so for example if I choose a screen blend over here you're going to see that I am lightening up my image like this effectively I'm creating more indirect bounces inside of my scene as well one of the cool things about working in Photoshop is that with this opacity setting you can choose how much the contribution of the indirect diffuse actually is inside of your scene like this and you can see it brighten up if we want to push it further than a hundred percent what we can do is that we can actually duplicate these layers as well so if I come over here and I duplicate it like that I can actually double the amount of indirect illumination which is inside of my scene and again you know I can adjust this ever so slightly like that as well so I can kind of like really tweak the colors and the balance of all of this just like that and again it's really really really easy to actually do so I could spend a lot of time playing around with my lighting settings inside of Maya to get this just right but thanks to working inside of Photoshop and I'll just make that kind of like as big as I possibly can on my screen like that so that you guys can see it very clearly you'll see that I've got now look again this very finite control for deciding how this image is going to look now again screen works good for anything that has illumination you could mess around with playing around with this but again you're going to see that there's some settings like add which really bright and other stuff like that all of the ones which are in this section over here kind of like from lighten to light in color they all increase the amount of pixel light there is in actually the image so if I come to something like the ambient occlusion this guy over here this is great for creating contact shadows and darkening specific parts of the image up and this immune occlusion file if I turn it on this tends to work very good with either a multiply setting over here just like that or it will actually work very well also with an overlay as well oh except it's making everything a lot brighter you might need a little bit of a alpha kind of light mask for this one specifically if you're using that this I'm going to leave it to multiply as you can see over here if I want to see this effect a little bit clearer I'm going to look for my refractivity map over here and you see that I've got the color of the bottle and I've got the color of the glass over here and again this is a nice one too I think either screen or ad will make this look fairly nice like that it's going to take all the black pixels and make them transparent and anything that's light and colored will actually come into here so I'm using just a screen here just so that I can see the bottom of this bottle over here and the bottom of the glass as well alongside these guys here so now if I turn on my ambient occlusion again I'm just going to turn that on and off you're going to notice that the shadows in this area get kind of like a lot more kind of like pronounced per se again I can play around very finely with how transparent my NV clusion lair is over here and I can make it clearer and clearer and I can make it darker and darker as I need to just like that even if I wanted to as well another thing I could do if I just single out the ambient occlusion for a second if I took this lair specifically and I colorized it slightly by pressing ctrl u to bring up the hue/saturation controls and press colorized over here added a little bit of saturation over here just to add kind of like the most subtle list of like blue little tints like that and then I'm just going to hit OK for now and turn on my refractivity and my indirect kind of like lights over here just like that you can see that I can add just a little bit of a blue tint to the shadows over here and that's going to really mix well with the little sphere over here as well which has some opaque transparent translucent shadows inside here as well so just added a little bit of color to my scene very very very very subtly again and again it's great that in Photoshop I've got this level of control that I can use just to really play around with my image just like that going forward again things like the specular direct which are the highlights over here sorry that's the indirect this is the one hopefully I'm looking for the specular direct light over here which I'll just throw on top of the refractivity so leave the refractivity behind and let's bring the specular in front of those actually even in front of the ambient occlusion probably will do a better job than what I had in mind like so okay so I've started reshuffling my layers over here and now I've finally got my direct specular actually which is the hard highlights over here in the right place on my image over here so what I can do with this is currently I can keep using my layer blending modes as well but if I had an alpha channel as well that specifically would only work with these pixels that would be quite useful for me as well so I could make a selection based on a color sample if I wanted to and go kind of like into select over here and to something like a color range and is kind of like all of the dark pixels per se you know and I could remove them like that there's just a little bit of gray left over like that but when I kind of like take this and I apply this to screen you're going to see again that we're going to be left only with those pixels over there just like that and if I wanted to kind of like just add a little bit of color to these highlights as well and specifically control what they look like as well well I could do that either in the screen mode specifically or again I can just start playing around with the actual values of these colors so if I kind of like play it around with them a little bit I think I'd probably have to have some very dark tones over here can I actually view them like that and again can I add some saturation to these over here if I wanted to have kind of like a little bit of an orange tint over here I could just manipulate that ever so slightly like that but I got to be careful that I'm not introducing colors into other areas like that most of the time I would try to avoid cutting things out and I would just work with the actual settings themselves so I'm going to change this to ad over here to create a very bright highlight over here I'm just going to knock it up and down just a little bit like that perfect okay then what I'm going to do is come into the specular indirect which is the reflections that are around over here in of the environment which appear in the bottle over here and I'm going to come over here and I'm going to choose screen like that so now I've got just a little bit of that there if I wanted to I could just boost the saturation of those highlights over there just a little bit to make the image just a little bit richer like that and again just knock it maybe down just a tiny amount like that perfect okay so I've got myself kind of like all of these nice little highlights over here and here's where my alpha can come in quite useful as well so if I've got my alpha channel selected like this over here one of the things I can do is that if I copy this alpha I can stick it in a mask into any one of these layers so if I took something like let's say this bottle over here which currently has like some very very very strong kind of edges over here I'm just going to make a selection around this area over here and let's say if I wanted to blur these edges just a little bit like that I'm going to exaggerate a little bit so that you guys can see it in the camera view just a little bit better as well normally I want to go this far but again just so that you see I'm going to go to blur and I'm going to choose something like a motion blur to an extent I'm going to put the angle that 0 over here and actually I didn't want to apply that straightaway so I'm going to come over here again and go to blur motion blur 0 pixels over here and again I'm going to look at this over here and that's the specular indirect channel I want to speculate channel over here there we go third time lucky there we go so I'm going to go to motion blur here there we go you can see that I'm actually blurring those highlights over there I'd normally do it just like a few pixels per se like make it really really really subtle but I'm just going to do it enough so that you can actually see that I'm getting some ghosting going around the bottle like that so I'm going to do 12 pixels again that's way too much but just so that you guys can see an example of what we can do with this and what I can do is that I still have hopefully selected my alpha channel over here so if I go into my specular dirac and I press the matte add mask button inside of Photoshop over here I'll just make sure that that thing here is not selected and again just add my mask over here so my mask is a solid set of white pixels there if I press and hold down the Alt key or the option key inside of a Macintosh and I click on the mask I'm going to view the actual mask inside of Photoshop over here so if i zoom out you see it's all currently white pixels but if I paste by pressing ctrl V on my keyboard over here you're going to see that I'm now pasting in the Alpha channel into this mask section over here so if I now come into here and I zoom into that bottle I've just softened off those highlights over here you can see that but now the mask is actually cropping out all of the pixels that were there so if I unlink the mask for a sec over here do I actually see the difference but you should see that actually now only the elements over here inside of the mask are actually visible and again I'm just going to take this over here I'm just going to move it wrong you can see that that's that mask edge over there so again using just a mask to select specifically the area that we actually want to add in so as we're creating kind of like blurs or little retouches or stuff like that or again if I had made a render pass with only the wine color inside here I could very accurately tweak what this actually looks like per se in the side of the bottle as well which specifically if I went into the refraction panel over here and only focused on this layer I could also go into Photoshop and make selections and stuff like that but it's so much easier if you make the correct render passes so all of these techniques kind of like allow us to actually change parts of the image really really really really quickly and again thanks to us being able to select things we can kind of like create and customize what our final image is going to look like for presentation purposes and again just to finish off with my little kind of like Tron colored kind of thing over here again wireframes if they're black on white that would be fine so probably something that looks a little bit more like this would be much more appropriate for what we want to do and basically I'd come into here if it was black on white and I just come in to multiply over here and you'd see that I have kind of like just a wireframe overlaid over there but again because I wanted to do something a little bit different like that and that again gives you a little bit of an unexpected grew out of just press control and I on my keyboard to again invert the colors in Photoshop if I come over here into my wireframe and let me just say that I choose something like screen over here you're going to see that I'm overlaying kind of like a white highlight which will mix with the colors inside of my scene as well looks a little bit weird in these sections over here so I could come over here around a little bit with my levels if I wanted to and just see but I can make maybe the colors just a little bit brighter brighter brighter like that and as I said before you know just having a little bit of a wireframe on top of your model is a good way of kind of like showing it off to people to sit so you can demonstrate how you've actually modeled thing but as I said before you know just actually having black kind of like and just having kind of like an overlay that's dark like this normally works much better it sometimes depends on what your scene actually looks like as well and again remember that you can soften this effect as well by adding a little bit more transparency to it if you so choose to rather than rendering it out all over again so all of this stuff is completely optional as well please remember that it's very very very important for us that we can take kind of like all of these elements and really really really get to customize what the image actually looks like inside of any image manipulation program like Photoshop or inside of a compositing program like nuke or in this very simple way inside of After Effects as well because all of these passes will work with stills like this but it's much much more interesting when you're actually playing around with animations because as the camera moves across your scene you're effectively creating Photoshop in motion with nuke so that's a little bit of a look at the render passes inside of Maya we're very much been talking about creating a OVS which are kind of like the main passes which are for the diffuse the specular the refractivity in this case and we've also looked at creating custom passes as well with the layer with the render layers system inside of my 2017 which can allow me to create material overrides and create a whole series of custom looks when we bring things into Photoshop we can go ahead and start manipulating things to a very very very high level of precision as well and we could move all of this information into other compositing programs as well so thanks very much for spending another week with me things have been a little bit slower this week a vicar's of tiredness sleep deprivation a little bit of feeling under the weather as well so I've given you this tutorial just a little bit later in the week but hopefully you'll enjoy it as well and thanks very much for staying in touch on the channel thank you very much for sending those comments and especially thank you very much for subscribing as well you guys have been absolutely great at keeping me going and I'm hoping to get a few more of these tutorials out to you guys very very very soon so until then I suggest you guys to keep learning and keep looking at all the other software that you can use to actually create fantastic 3d imagery and I'll be back hopefully next week and I'll be able to get you guys another Mya tutorial so until then keep learning and keep strong and I will see you next time take care

Channel: yone santana

Views: 100,719

Keywords: Maya, 2017, Yone, Santana, yonesantana, 3D, tutorial, Rendering, Arnold, Render, Layers, Pass, Passes, AOV, AOVs, UK, Autodesk, learning, beginner, how to

Id: b4cmYQGt5t4

Length: 61min 35sec (3695 seconds)

Published: Thu Dec 08 2016