Mimic Volumetric Fog Using Only Compositing (Blender Tutorial)

what if i told you that this picture was rendered without any volumetric fog and that there was a way to easily replicate the look of volumetrics with nothing but simple compositing in blender i am going to show you how to do just that you can see that there is no volume metrics in this scene so there's no light rays or fog of any kind so the first thing that you want to do is go over to viewport layer properties and enable the missed pass after you enable miss pass go over to material preview click on the drop down arrow and switch it from combined to missed and now we can see the missed pass and since we enabled miss pass in the world shading tab you can now see that we have a tab for the miss pass and you can mess around with the parameters of this because the fog would realistically be taking up the whole scene we want to start it at zero because we could if we started at any other point then the whole scene wouldn't have fog if that makes sense so put it at zero and bring the depth to anything that fits your scene for mine i found that 50 worked but for yours it could be lower or higher now go back to the layer properties tab and scroll down until you find a mission and check emission because we're going to need that as well so now that you have both of those checked you can render your scene [Music] i'm just going to minimize that screen and go over to compositing now the only thing i've done so far is add a viewer node so you can see what i'm doing so the first thing that we need is a mix node we're going to change it from mix to add we want to combine the image and the mist with this add node so just plug it into the bottom and now you can see that we have our mist or our fog but if you want to adjust a little more you can add a color ramp node and put it in between and adjust the colors so if you want the whole thing to be a lot foggier you can bring the white towards the black to be a little more realistic you could probably increase the brightness of the black and make it a little more foggy closer to the camera to make the fog look a little more natural you can adjust the color on your color ramp according to the lights in your scene so in this case since i have orange light coming in i'm just going to make it a little bit orange not too much i think i'll bring it in just a little bit okay so that's pretty much all on the mist so now we're going to do some light rays so to do that you just need to add in a sun beam node and plug the image into that duplicate this add node and put it right there and then put the sunbeams into the bottom of the add node so nothing's changed yet because we have to increase the array length now we have light rays this x right here allows you to adjust the position of where the light rays are coming from so you want to try to line it up with where your sun might be coming from so here i'm just going to put the x up in the top left corner and move it around until it sort of fits with the lighting i already have going on now here is where we have a problem with this sunbeam node since we just plugged the image straight into it it's taking every highlighted area of the image and stretching it out to where it makes a sunbeam and we don't want that we just want it to be where the windows are we want the light to be coming through the windows like it would naturally do so to fix this problem we instead need to go back to our 3d viewport and we want to add in a plane bring that plane over to wherever you want your light rays to come from and rotate it however you need it in this case i just needed to line up with all the windows and cover all the windows so it's covering all the windows but it's also blocking the sunlight so to fix that i'm gonna uncheck this shadow box and now we can see the light coming in now what you need to do is make a new material for your plane and change it from principled to emission and again you don't have to do exactly what i do because you're gonna change the emission strength to whatever you need but i'm just gonna do about three and then also make it a little tan like i did my sunlight okay now that we have our plane in place we're gonna re-render your image [Music] okay now backing compositing instead of putting the image in the sunbeams we're going to use this emit pass and put it in the sun beams and now instead of taking all the highlights of the image it's only making sunbeams from that emissive plane so instead of getting the stretching on the monkey heads and every highlight in the scene we're only getting it from the windows like it really should be and now that i've fixed that i'm gonna try to line everything up just a little bit more now that we have fog and sun beams in we want to add in a glare node because if you've ever seen fog on a normal image with normal volumetric fog it creates a bloom around all your light sources so we want to replicate that of course so change the streaks to fog glow i just like to put the quality on high because why not but you can do low or medium now this last step is completely optional but you can add in a bokeh blur to the very end just bring the size down to like .05 something very low because you don't want a lot but i just think that fog tends to kind of blur things out a little bit so adding this blur kind of just makes everything look a little better in my opinion but you don't have to have it because you may not like it in your scene okay so that's pretty much it you might have to adjust certain things accordingly to what you're trying to make but that's basically all you need to do so i hope you learned something for this i hope you can use this and thank you so much for watching bye

Channel: Lane Wallace

Views: 54,790

Keywords: Volumetric, Compositing, Lighting, Fog

Id: TH2ZoEvhsTs

Length: 6min 31sec (391 seconds)

Published: Mon Sep 20 2021