Render Faster in Octane Render

hey it's dave from cg shortcuts today we're going to do this we're looking at our top tips for rendering faster in octane [Music] so a few people have asked us why their octane renders are still so slow so we thought we'd put together a tutorial with all of our top tips on increasing your octane render speed and optimizing your scenes we've also made a bit of a checklist on our website so you can go through all the steps one by one next time you're rendering one of your projects we'll leave a link down below to where you can find that and let us know in the comments if you think we've missed anything out also if you want to learn more about rendering and octane you can check out our new course the ultimate octane master class which we've just launched a couple of weeks ago so a big shout out to all of the students who have joined us so far we're looking forward to seeing your epic octane renders okay let's get into it so we've got a simple scene set up here with a statue and the octane logo so let's fire this up in the octane live viewer and see what render speed we're currently getting and the first time we do this there's always going to be a bit of a delay because we need to send our scene to the renderer and load everything up in the vram of our gpus and this particular scene takes quite a while to get going and as soon as that's done we start to see our image and with our current setup it's estimating this frame is going to take about 15 minutes to render which for a pretty simple scene is a little bit excessive so rather than waiting for it to finish let's go and take a look at our octane settings here and you can see we're using the path tracing kernel which is what i use most of the time but by default the max samples are set way too high at 16 000 samples and you can see at this point we've only done 736 samples out of the 16 000 max samples which it's guessing is going to take 12 minutes to reach which is definitely not what we want for a single frame so the very first thing you'll probably want to do in most cases is bring this way down to something more manageable and i usually just take the six out and bring this back down to 1000 samples and we'll just refresh this and again there's a slight delay while we send everything to the renderer and we'll let this render play out fully so we can see how long a frame is going to take for us at a thousand samples and i'll just speed this up in the tutorial so we won't need to sit around and watch it render and you can see that render has finished and it took 45 seconds to complete or to reach the 1000 max samples but even a thousand samples which is still a pretty high value the image hasn't cleaned up fully we're actually getting fireflies or hotspots over everything so before we start optimizing for speed we'd better fix these first and we could increase the max samples higher until those fireflies clean up but that's going to slow our render down again so i prefer to use the gi clamp to clamp our global illumination rays and clean up those hotspots and you can see this value is also set way too high by default so i usually knock this down to a value between 1 and 10 and you'll see if we do that and i'll just fast forward that render again not only do we bring the render time down slightly but we've also cleaned up all of those fireflies and we're getting a much cleaner image so a lower value can limit the length of the gi rays and prevent it from returning errors which can give us hot pixels okay so now that we've lowered both of these values let's try and bring this render time down even further so next in our settings here we have the diffuse and specular depth which are also set super high by default these dictate the amount of diffuse or specular bounces in our scene or the depth at which data is collected and we don't want these values to be any higher than they need to be and to figure out the optimal values we should use in this particular scene let's first store our current render in the render buffer so we've got something to compare with then we'll take these values all the way down and you can see by doing that we've dramatically reduced that render time to just seven seconds now but our new render the one on the left here isn't looking so great you can see we don't have any light bouncing around in our scene anymore so it's looking very cg and not very photorealistic light in the real world does bounce around and reflect off surfaces so we definitely want something more like this but with the lowest values here that we can get away with so if we put this back in the middle here we'll tweak these settings and for the sake of speed we can use our render region tool to concentrate on a particular part of our image so we don't need to wait for the whole thing to render let's just drag this over here and we'll slowly bring these values up until we get a bit closer to this result these were originally set to 16 so i'm hoping we can get a similar result with a much lower amount of bounces so let's bring up the diffuse depth and at three bounces we're already starting to look much closer to what we had before but we have reduced the render speed quite a bit and we only want to bring this up to the minimal amount where we're happy with the result and i think six gives us an almost identical look to what we had back when we had this set to 16. so six is where it starts to have very little impact on the look of our render let's just check the lower part here and you can see we are slightly darker in this area but that might actually be because we need to increase the specular depth as well these are specular materials on here so let's see if we can bring back some of that extra light so we'll slowly bring this up until it's not having much of an effect and i think at three we're very close to what we had before it is slightly darker but i'm not sure that bothers me too much for the sake of speed i think we could even get away with lowering this back to two which looks fine to me so let's turn off the render region and just let that render through to completion and we're now down to 38 seconds so we've shaved off a few more seconds doing that and if we compare before and after we haven't lost too much quality either just a little bit of that extra bounce light which i think i can live with in exchange for a faster render so let's turn the comparison off and before we go through some of the other octane settings we can use now might be a good time to make sure our scene itself is optimized so let's minimize this and we'll switch to a zoomed out camera view so we can see our whole scene and here's our statue on top of the block here and we can also see the three lights we've got set up in our scene which we'll look at a bit closer a little later on but we've also got a load of objects down here as well which aren't actually even visible in the shot they're also not having an effect on the lighting and they're not visible in the reflections either so we really don't need those in our scene not for this particular shot anyway and to keep our renders running at the absolute fastest speeds we need to make sure our projects are as streamlined as possible so we always want to be removing everything that's not necessary so if we take a look in our scene null here we've got a cloner object which is cloning all of these logos and before we do remove this a quick tip for optimizing the render speed of cloners is firstly rather than using the standard cloner object that comes with cinema 4d you'll have faster render speeds by using octane's own built-in version of the cloner the octane scatter which gives you a lot of the same settings and features but it's a bit more optimized for rendering in octane but if you are set on using this one instead you just want to make sure if you can that you change the instance mode from instance which is currently contributing to a 38 second render we want to switch this to render instance or multi-instance which when doing that knocks us down from 38 seconds to a 33 second render and that's because we're no longer cloning each one of these as a separate object or with their own geometry and data we're just taking the original object and cloning or copying it however many times which ends up saving us some ram and speeds up the render and nine times out of ten i would leave this set to a render instance but as i said before we don't need this in our scene so let's delete it and see if it affects our render speed even more and it's done exactly that we've managed to shave off another three seconds so we're well on our way and now that we've gotten rid of the objects outside of our shot let's see if we can optimize what we do actually see in the camera view we don't want to remove any of the walls or even the floor in our scene even though they aren't directly visible in our shot but the light is actually bouncing off those surfaces so removing them will affect the lighting in our scene which we probably don't want but we might be able to optimize the statue itself it looks quite detailed in our viewport so it may have a very dense mesh and if we switch to the wireframe mode here you can see that is exactly the case this is a 3d scan model and i know for a fact that there's over a million polygons on here which is not really ideal if you're looking for super fast renders octane does do a pretty good job of handling dense meshes but everything will still need to be sent to our gpus and you can see in our render stats here that we have two gtx 1080s in this machine and the total size that's being stored in the vram of those gpus is already 2.7 gigabytes out of a maximum of 8 gigabytes which is quite large considering we've only got a pretty simple scene here and we need to keep an eye on this because if we go beyond the vram limit your scene won't actually render at all and for the sake of speed we always want to keep our geometry nice and tidy and with good topology and the minimal amount of polygons as possible so if we take a look inside that statue null here this is that super dense scan mesh of our statue but i also have a low-res version so let's see what happens to our render speed if we switch our high-res mesh with a cleaner low-res mesh and we'll just refresh this as well and you'll notice we get a much quicker start now that the initial send is much lighter and again we've dropped another three seconds off the render and all these little speed increases are beginning to add up obviously though if you are going to use a lower resolution model you'll need to make sure it's a good one this is just a quick proxy i've made up and you can see we've lost quite a bit of detail with this model another option would be to bake the finer details into a displacement map and use the low res models with displacement instead rather than a high-res mesh just be careful with displacement maps as well though because they can slow down your renders if you overuse them anyway in this particular case i think we'll sacrifice the three seconds off our render and use the hi-res mesh instead alright so we're back at 31 seconds of frame and seeing we've now cleaned up the objects in our scene we should also make sure our materials are nice and clean as well if we take a look at the statue again you can see we've tried loads of different materials on here while we've been doing our look development which are all of these guys down here and it looks like we've piled these on until settling with this simple white shader which is what we can see here on our models so all of these materials are still being sent to the renderer and stored in the vram which in turn is adding to our render times so we don't want any unnecessary materials over here that we're not using so let's grab all of those and just keep an eye on the amount of vram we're using here as well as the amount of textures we're rendering here there's actually 24 texture maps being calculated at the moment but if we remove these we're now down to 1.4 gigabytes from 2.7 and we're only using three texture maps now and we've also lost another second off that render time which isn't huge but like i said it all adds up we also want to remove those unused materials from our library here so we can keep everything streamlined so we just need to go to edit and delete unused materials okay so we're at 30 seconds now but there's something else we can do to optimize our scene to bring this down dramatically we've optimized our objects and materials but what about our lighting we're currently using three octane area lights to light our scene and we can find those guys over here in the lights null and we'll just isolate these so you can see the effect they're having on our scene we've got this light above our scene then this guy is giving us some rim or back lighting to bring the objects out from the background a bit and finally a bit of fill light that's brightening up those dark areas in the background and these three lights are actually the biggest reason for this slow render octane area lights are actually quite slow to render there's quite a lot of calculations going on with these they're all emitting different levels of light and shadow and even their reflections are being calculated in the scene but what if we could simplify our lighting and turn these three lights into one much more simplified light source and we can actually do that with the most efficient form of lighting in octane with a hdri map or a hdri environment and it just so happens i have one of those already set up and ready to go in our scene and if we go into the environment tag here's the hdri map i've created and i've actually made this by baking the current lighting setup into a single hdri image which is what we can see here and i'll just give you a closer look at that you can see these three lights are baked into here one two and three and because they are actually contributing light to the scene i've also baked the walls these here and the floor into this as well so we've basically replicated our entire scene lighting into one single hdri map and if anyone's interested in seeing how that can be done let me know in the comments and i might be able to make another video but let's move this out of the way and see if this can help us reduce our 30 second render if we turn all of these area lights off and we don't need our walls or floor anymore because they're also baked into the hdri map and now if we enable the hdri environment let's see how fast our render is now way faster we're now down from 30 seconds a frame to a much more manageable seven seconds and all we did was bake all the lighting information into a single hdri map so our scene is much lighter and much faster and things don't look all that different over here but depending on your scene you might not be able to use this method but for this scene it's working great and it's definitely a good option if you're rendering stills and the good news is we've still got a few more tricks up our sleeve to bring this down even further so now that we've optimized the scene itself let's head back to the octane settings and we want to scroll down to the bottom here to the parallel samples and max tile samples and these are going to allow us to utilize our remaining vram to fire more rays into our scene at a much faster rate and using this will depend on the amount of vram available in whichever gpu you have installed we can see down here that we have plenty of vram available in our 1080s so we should be able to utilize this feature to speed up our render so currently we're down to seven seconds per frame and we're using 1.2 gigabytes of vram but let's see what happens if we increase these values and we'll refresh the render and it's made a liar out of me in this particular scene it hasn't affected the render time much however it did double the amount of vram we're using so this isn't going to work for every scene but it is still worth trying if you've got the spare vram and for some scenes i've managed to get a pretty decent speed improvement with this feature not to worry though we've still got a few more options we can try here including the adaptive sampling so let's turn that on and straight off the bat we've got a one second speed increase and we've also got a new noise tab appearing here which gives us a pretty funky looking green filter basically these green areas represent the pixels in our scene that have reached a minimum sample value that we've defined by the threshold down here and when they reach those minimum samples and are therefore determined to be free of noise the adaptive sampling switches those pixels off or stops them from being sampled any further so it can concentrate on the areas of the image that still need cleaning up so basically it's adapting to the areas of the image that need more time to clean up and to smooth out the noise so if we want this to render even faster we want more of the image to turn green before the render finishes so more of the pixels are switched off and we can concentrate the calculations in the areas of our scene that have the most noise so to do that we need to increase the noise threshold which is going to let us move on from the areas of our image that need less samples a lot sooner if that makes sense so let's bring this down to something like 0.5 and we'll see if we can now beat a six second render so let's refresh this and we should see the less noisy areas of our image turning green and switching off sooner and that's exactly what we get to the point the entire image turns green before it reaches the 1000 max samples and we've shaved one more second off that render and if we take a look at the render itself it doesn't look too bad and we can make this even faster if we bring the minimum samples down as well at the moment a pixel can only switch off once it's reached a minimum of 256 samples so only after that can it go green but if we lower this value it can switch those pixels off sooner when it's reached just 100 samples so let's see how quick our image turns green now we'll refresh this and that's switching pixels off much faster and our render is now complete in just three seconds so we've almost half the render time however if we look at the render itself some areas of the image are now looking a bit too grainy for my liking because the lower minimum samples can also mean some areas of the image will switch off before they've received enough samples to clean up the noise so you are going to have to play around with these settings to really optimize the adaptive sampling in your particular scene but it's definitely worth doing to get those render times down but we're actually going to turn the adaptive sampling off for now because i want to show you another setting we can use to dramatically speed up your renders so we're back at seven seconds of frame but there is one setting that we've overlooked and it's probably the most important setting there is when it comes to render speed and that is the max samples themselves obviously the lower we make this the less samples we'll need to calculate and the faster the render will be 1000 samples gives us a fairly clean image but could we get away with lowering this even more let's try bringing this all the way down to 300 mac samples and refresh that let's completely slash those render times down to just two seconds now which is our best speed yet but our image has finished rendering without enough samples to clean up that noise so we're left with a fast but pretty unusable image however there is actually a way we can render with really low sample rates but still get a super clean image and that is with a fairly new feature in octane which i think was introduced in version four and we can find that over in the camera tag under the camera imager which we've enabled here and that's the spectral aid noiser which if we enable still gives us a two second render and hasn't actually made much of a change to that image yet but we also get this new dmain button which is our denoised pass so it's basically going to analyze the noise in our render and use a pretty sophisticated algorithm tailored to the noise patterns in octane and try to smooth everything out similar to the way a denoiser filter might work in a compositing application so let's see if that manages to clean up this noise so before and after and i have to say it's done a pretty amazing job of cleaning up that image so using this feature can allow us to get away with using very low max sample values which can give us super fast renders while still giving us a pretty decent looking image but just keep in mind the lower this value the less samples the denoiser has to work with so if it's too low you might end up with a lack of detail or blurring in your images and if you're planning to render out animations this can also lead to flickering as the denoiser struggles to clean up every frame so like most of these settings you might need to tweak this depending on your scene setup okay so there's one last thing we'll look at to drop that render speed and that is by changing the render kernel itself as you can see here we're currently using the path tracing kernel which i tend to use most of the time because it's the best balance of realism and speed but we could switch this over to the direct lighting method which is a biased render kernel and also happens to be the fastest so let's give that a try and see if we can get this down to one second and we've actually done even better that render took less than a second now which is a huge change from the 15 minutes we originally had and the denoiser pass will also work fine with the direct lighting kernel keeping everything nice and smooth but without that we do get a little bit of noise happening in here and that's because we've now defaulted to an even lower max sample rate than we had before so just to match that let's put that back at 300 and that'll clean up a bit more of that noise and we're up to a one second render which is still pretty amazing especially with this nice smooth de-noise version but you will notice the render itself looks quite a bit different to what it looked like with the path tracing kernel and that's because the direct lighting kernel has a few different global illumination modes we can use gi none mode is the fastest to render but it doesn't give us any light bounces so it's fast but not very photorealistic then there's gi ambient occlusion which is what this kernel defaults to and this mode fakes the indirect illumination using ambient occlusion which is also not very realistic but it's still quite fast and the third option which is the slowest of the three is the gi diffuse mode which is the closest we're going to get to the look we had back in the path tracing kernel and you can see we're getting those indirect light bounces and it looks very similar to what we had before however we're down to a super fast two second render let's try matching our depth settings to what we had before as well so we'll make the specular and glossy depth 2 and the diffuse depth 6 which gives us an almost identical result but using the direct lighting kernel instead brings our render down to just two seconds so if you can get away with switching to this kernel it's definitely a good option but like i said as a biased render kernel it's not going to give you the level of photorealism you might get with the path tracing or pmc kernels but switching to those means you'll have to sacrifice some render time so i'm pretty happy with this particular scene now we've cut our render time down to 15 or 20 minutes of frame to just two seconds per frame so we could happily send this off to render now and we could also try increasing the parallel samples and max tile samples in the direct lighting kernel to speed things up even more or we can utilize the adaptive sampling again so there's plenty of options when it comes to optimizing your scenes for rendering and octane and one last bonus tip before we wrap this up it's always a good idea to make sure you're utilizing all of the compatible gpus you have in your machine like we've done here with our two gtx 1080s and you can check that over in the settings tab under devices and you just want to make sure you've checked the graphics cards you wish to use and this is also a super important element when it comes to gpu rendering the better the graphics card the faster the render and the more cards you have the better so having two gpus in this machine will give us twice the speed of just having one and that's it for our top tips for rendering faster and octane and we'll put a link to our website below where you can find that full checklist you can go through next time when you're setting up your own projects if you're interested in learning more about octane and all the settings we've looked at today we cover just about everything there is to know about the software in our new octane ultimate master class which is also available on our website so we'll have you rendering like a pro in no time okay that's it for this tutorial happy rendering and we'll catch you next time thanks for watching let me know what you want to see in the comment section down below or you can leave a like or dislike and don't forget to subscribe and click on that little bell icon for more videos and free stuff there's loads of extra resources on our website and you can win epic cg prizes in our monthly challenges check out cgshortcuts.com for more details catch you next time [Music]

Channel: CG Shortcuts

Views: 74,821

Keywords: Octane Render, Octane rendering, Render fast, Render faster in Octane, Octane Renderer, rendering in octane, c4d, Render faster, cinema 4d, Render speed, tutorial, mograph, tutorial animation, motion graphics, octane, cg shortcuts, cg, free project, template, cinema4d, animation, 3d, motiongraphics, motiondesign, 3d animation, cgi, rendering, design, graphics, dave bergin, c4d tut, cinema 4d tutorial, c4d tutorial, maxon, cgshortcuts, animated, render, 4d, cinema, blender, effects, 3dmax, Model

Id: Nw_Dy_M_hMc

Length: 25min 21sec (1521 seconds)

Published: Fri Jan 29 2021