The Secret to Beautiful Renders

have you ever had this problem you spend hours creating models for your scene you put lots of thought into the composition you give everything nice materials but the result just looks really underwhelming it's flat and boring and you can't figure out what you did wrong a lot of 3d artists have this problem because they don't know the tricks to improve the quality of their renders so in this video i'm going to go through just about everything i wish i knew in the first two years that i used blender before we begin i just want to give a quick shout out to the sponsors of this video nvidia and scan the nvidia rtx studio program certifies devices intended for creative workflows so you can be sure that any device with the studio badge will have great performance in apps like blender after effects and davinci resolve scan has a great range of rtx studio devices on the website including pre-built desktop and laptop computers check out the link in the description to visit the rtx studio range on scan first up let's talk about how we can improve the overall look of the scenes if we go down the color management tab we can instantly improve 90 of renders just by changing the look mode from standard to a higher level of contrast i like medium high or high contrast the default in my opinion is a little bit flat and everything just pops better if you up the contrast slightly we can also change the color transformation here too there's several modes to choose from the main ones you'll probably use are standard or filmic filmic tends to give more thought or realistic results it's the default these days and i would suggest you just leave it that way the false color mode is a really handy tool it's not made for rendering but it's an easy way to check the light levels in your scene it shows different brightness levels as different colors with red being really overexposed so if you say lots of red areas in your render those are probably going to be too bright and you want to turn the lighting down you also might need to change the exposure value or the gamma which can also be done in the color management tab finally you can set your own custom curve for the contrast now let's talk about cameras a lot of people make the mistake of not really touching the camera settings and i think that's a shame because it's a really powerful set of tools especially if you're going for a more realistic style by default blender uses a 50 millimeter camera smaller focal lengths than this can fit more of the surroundings into the shot but they also create a lot of perspective distortion vloggers really love small focal lengths because it allows them to fit the whole face and the background into one shot even though they're only holding the camera at arm's length large focal lengths over say 80 millimeters are zoom lenses they used to photograph things in the distance they tend to have very little perspective distortion but you can also fit less of the subject matter into the frame a good way to think about lenses is like this if you wanted to photograph a skyscraper from the very bottom you'd use a small focal length in order to be able to fit the whole thing in the shot but if you were in a helicopter five miles away you'd use a large focal length and zoom right in on the building from a distance next we have depth of field real cameras can only focus on one specific depth you can create an empty object in the scene and set this as the focal point for the camera then you can move it around to adjust where the camera is focused changing the f-stop value will alter the amount of blur in the scene this blur is called bokeh or bouquet if you fancy bokeh takes on the shape of the camera's aperture we can simulate this by changing the blade and rotation settings the ratio value at the bottom is used to replicate an anamorphic lens i better quickly explain what an anamorphic lens actually is imagine that you're a film director in the 1950s and you want to shoot widescreen format but all the cameras and projectors at the time are made for 35 millimeter film so how do you make a wide screen image fit under a 3 2 aspect ratio well you could shrink the image down until it fits horizontally but then that wastes a lot of the film's negative space on the top and bottom when you blow the image back up you're going to lose some quality and everything will be blurry instead we can shoot the image at normal scale but we'll use a curved lens to squash down the image horizontally so that it fits on the film then we can use another anamorphic lens on the projector to stretch the image back out in the opposite direction and i'll restore the original widescreen shot directors love anamorphic lenses because they have this really weird effect on bokeh highlights and lens flares get all stretched out across the screen so if you're going for a really cinematic look this is an easy way to do it we can emulate anamorphic lenses by changing the ratio value numbers below one will stretch the book route horizontally and numbers higher than one will stretch it out vertically if you're working on an animation you're going to want to enable motion blur that's the effect that occurs when an object moves while the camera shutter is still open it doesn't just happen with cameras it happens with your eyes too you know that if you move your hand really quickly in front of your face it looks blurry so it's really imperative if you want to replicate real motion to use motion blur unfortunately motion blur takes a very long time to render however if you are using the latest rtx 30 series gpus you'll have access to gpu accelerated motion blur it's already been integrated into blender since version 2.9 i think it was and in my experience it allows you to add motion blur with a very small hit to performance i actually did a few different render tests like this and i found that nvidia's gpu accelerated motion blur was about four to six times faster than the blender default we can also drastically improve our renders in the compositor if you open the compositor tab and select the use nodes checkbox you can add nodes into the workflow and change the image colour balance is probably the most basic of these nodes letting you tweak the colours of the render cgi always looks a little bit too sharp for my liking so i usually add the blur node and i set it to 2 pixels if you add a glare node into the scene they'll add lightning effects based on the brightest parts of the image i personally set this to fog glow most of the time which comes in really handy when you're trying to make anything from lightsabers to neon signs the lens distortion node can be used to add some chromatic aberration to the image that's the color fringing you sometimes see around the edges of objects and photographs it's caused by the different wavelengths of light being refracted as the end of the lens try to use this subtly please people especially video game developers have a really nasty habit of abusing this effect i rarely turn the dispersion value up higher than 0.2 now how about we add some volumetric effects these are really handy if you want to add things like fog or mist or light rays into the scene create a cube and scale it down to fit the scene add a new material then delete the principle shader add a principal volume shader and plug it into the volume slot changing the density will alter the amount of visible volume in the scene the anisotrophy will change how light interacts with the volume as it enters it and you can also change the color of the volume too if you plug a noise texture node into a color ramp and then you use that to drive the density you can change where the fog is applied that can give you all sorts of different effects like rolling fog and clouds now let's talk about lighting lots of people make this mistake they have an outdoor scene lit by either a point light or an area light they notice that the objects in the background are much darker than the objects near the light source so they keep cranking up the strength of the light until everything in the background is lit but that makes everything in the foreground way too bright or they keep adding more and more lights in the scene trying to fill out the dark areas but then you end up with this really patchy uneven lightning and you have multiple shadows on the ground either way it looks nothing like sunlight light follows the inverse square law which basically just means that every time you double your distance from a light the amount of light that you receive decreases by a factor of four so if you're right next to a light bulb it's incredibly bright but it quickly becomes very dark as you move away since we're 93 million miles away from the sun we can barely see this effect on a human scale you're not going to see the sun get noticeably darker just by walking further away for this reason if you're working on an outdoor scene that's lit by the sun use either the sun lamp or a hdri if you're working on an interior scene or an exterior scene that's lit by artificial light there's some really cool tricks we can do here too by default point lights around they emit light evenly in every direction but real light bulbs don't work like this we can replicate real light bulbs using ies profiles which can be downloaded freely from the internet ies files are made by light bulb manufacturers and they accurately describe the falloff of real light bulbs once you've downloaded an ies file from the internet create a point light in the same set the power to one and then select use nodes in the shader editor add in an ies node and connect it to the strength then select external and load in the ies file you just downloaded this particular ies file is a replica of a real led spotlight so it's sending the light mostly downwards and creating this nice shape we can change the sharpness of this effect by altering the radius of the bulb there's probably over a hundred thousand is profiles online and a lot of them do look the same so you sometimes have to go through quite a few before you find a good one another good trick to make your interior lights more realistic is to use accurate colors led and neon lights can be pretty much any color but most house light bulbs tend to follow a scientific principle called black body radiation you can add a blackbody node and connect it to the colour input of the emission shader most household light bulbs range from 2700 kelvin to 7000 kelvin let's quickly talk about how to reduce noise it's fairly common to say really nice work be ruined by overly noisy renders which is a shame because there's lots of tools and blender to combat this let's quickly just talk about why noise happens in the first place one day i'll probably do a video all about how path tracing works but for now here's an incredibly simplified explanation the camera view gets split up into a pixel grid a simulated light ray gets fired from the camera it hits the object bounces in a random direction this first pixel here haven't hit the strong red light so we shade this in bright red the second pixel also hit that same red light but because it bounced off an object first some of the strength gets absorbed so it gets a darker shade of red the next light ray flies off into space it doesn't hit any light so this pixel just gets shaded in dark this last pixel happens to hit the blue light so this gets a light blue color so now we've got four pixels right next to each other each one has very different colors and values here's a render of the exact same thing with one sample i've made it really low resolution so you can see the individual pixels looking at this scene you can see the exact same thing that i just described we have really bright pixels that hit the light directly really dark pixels that bounced around a lot before they reached a light source and we have pixels that didn't hit a light source at all so they're just grey if we increase the sample count what we really do is we run the same test multiple times for every pixel each time the light bounces in a different direction then we just average out the result of all those samples unfortunately that's a hell of a lot more calculations which slows down the render time luckily we have quite a few tools to combat noise in blender go to the render properties tab and open up the light path drop down menu the full glossy setting reduces the impact of bright highlights on the scene which reduces the noise i usually set this to about two you can disable caustics which sometimes reduces the noise but it can make your interior scenes very dark if the primary lighting is coming through a window you can also clamp the direct and indirect light strength that basically sets a limit on how much a single sample can affect the pixel strength for interior scenes i usually set the direct to a number between 8 and 30 and i use 5 to 10 for indirect you don't want to clamp the line too much otherwise everything will start to look really dark and washed out you can also change the physical size of the lights in your scene to reduce noise larger lights are easier for the samples to find so they produce less noise but obviously if you change the size of the light you're going to change the way the light looks including the softness of the shadows we can also artificially remove some noise from the scene using a denoiser blender currently supports two main denoises there's the urban denoiser which was developed by intel and this nvidia's optics ai denoiser which is my personal favorite it's faster than the open denoiser it uses far less vram and in my opinion it produces slightly better results the optics denoiser works on any nvidia gpu from the gtx 900 series upwards although it was designed with rtx cards in mind so you definitely get a performance boost if you're using a newer card this next tip is a little bit specific but i see people doing this all the time and it drives me mad when most people go to make an electric sign they'll just get the image texture for the sign they'll plug it into an emission shader and they'll call it a day in my opinion most of the time this looks terrible but there's a number of things we can do to really improve it first of all let's remove the emission shader and we're going to plug the image into the base colour and the emission colour slots of the principle shader since this sign is made from slightly transparent plastic increase the transmission value a little bit then we can add a grungy image texture like this into the roughness value the dark parts will be smooth and the light parts will be rough we can tweak those values using the color ramp node now we have some visible grime on the plastic and it looks a lot more realistic we can also add just a little bit of warble to the sign add a must grave node plug that into the height of a bump node and then plug that into the shader's normal slot you can play with the strength and the distance and the scale on the musgrave until it looks nice it's also very rare for a real sound to be evenly lit they tend to have a light bulb in there somewhere that creates a hotspot you can create a mask in photoshop to control the strength of the light but i'm going to show you a method to do it with some really simple nodes just add a gradient texture node into the workspace and add a textured coordinate node as well connect the object coordinate data up to the vector of the gradient if using the node wrangler add-on you can just control shift and click on the gradient to view the output change the gradient mode to spherical and that'll give us a circle now we can add a mapping node between the coordinates and the gradient and we can play with the scale and the location and all the other settings until we get a mask that we like this is going to control the strength of the light the light parts will be brighter and the dark parts will be darker but if we plug this into our mission strength we can say that it is a little bit dark right now we can increase the brightness really easily we're just going to add in a math node we're going to set that to multiply then we're going to turn the strength up to in this case 10. now that's better but we have one last problem with the mask it's a little bit too sharp let's take the gradient output pass it through a color ramp node and set that to ease what ease mod does is it just smooths out the transition between the light and the dark parts now our sign looks a lot better but as a final touch let's add a little bit of dirt and grime create a new principal node give it a dark black color and give it a really high roughness value too add a mix shader node and plug that into the sign at the top and add the dark material in the bottom we already have this grunge texture here in the editor so why don't we just plug this straight into the mix factor [Music] we can add another color ramp in between the texture and the mix node to control the thickness of the dirt and where it's applied personally i like to keep this quite sill now if we add all these other compositing tricks and things that we've learned today we go from this image to this image i don't know about you but i think that's a hell of a difference so in a nutshell that's just about everything i learned to improve my renders for the first few years that i used blender remember to check out the link in the description to view scans awesome range of nvidia rtx studio devices they have a huge amount of options on the site whether you're a hobbyist or a professional creator they have something for every workflow and budget

Channel: DECODED

Views: 47,759

Keywords: tutorial, DECODED, Blender, blender 3d, software, computing, classes, blender for beginners, blender online, free 3d modeling software, open source software, 3d software, vfx, vfx artist, tips for blender, how to improve renders, make better 3d art, get good at blender, blender tricks

Id: ELz6EpkAQR8

Length: 17min 5sec (1025 seconds)

Published: Thu Nov 11 2021