My 5 Best Tips For Realistic Liquid FX Simulations (3Ds Max, Chaos Phoenix Tutorial)

hey everyone and welcome back to the redefine effects YouTube channel so today I want to address five of the most common mistakes that I see people make before we get into it I know that it's been a minute since I uploaded it's been a few months I took a while to make my first course on top of being busy with client work but I am back and I will be uploading regularly again just like I used to so if you are not subscribed yet now would be a good time to subscribe so you don't miss out on all of the upcoming content alright so the number one mistake I see people make is that they're working in the wrong scale so you might have noticed in my videos I will always start by going under customized unit setup and tell you I'm working in metric centimeters one unit is one centimeter if you want your results to look the way they look for me you have to be working in the same scale and don't get me wrong you can be working in any units you can be working in meters or inches but you just have to be working in something that makes sense for whatever you're working on and you have to remember that the objects should be scaled according to their real-world size so if I make a box next to this glass just to measure it the box is about 1213 centimeters high which is about how high or how tall a glass should be in real life now if I go under customized unit setup and I change this to meters and make one unit one meter now if I make the box it's 13 meters high even though visually nothing has changed so don't forget that this this grid doesn't mean anything you know you might say well this grid is probably pretty big so I'm gonna make my object small but small here is still you know three meters big it doesn't really matter how big it is in the scene the only thing that matters is what unit setup you're actually in so right now if I were to pour liquid out of this sphere into this glass I would be pouring the liquid into basically a two-story building and it will probably take forever to sim we'll never look right people then try to compensate for that by going under grid dynamics and you know they're increasing the resolution way high up and then they will go under dynamics and try and play with the speed of the liquid none of which will ever really fix the underlying issue which is the issue of the scale so that's something to definitely keep in mind all right so just to get the point across I made these two previews for you guys so the one on the right is the correct scale the one on the left is the exact same looking scene you know it still looks kind of innocent like everything is right except the scale in this one is in meters so it's basically an unfixable disaster while this one is looking the way it should look okay so the number two tip that I have for better liquid simulations is you have to have the patience to raise the resolution of the grid and then let the simulation run through I know what it's like to want to put a result out there but a lot of times I will see a really good set up but the person has just not raised the resolution high enough for all the detail to show up and a lot of times what makes these simulations really pop is when you see all the small detail all the little drops all the little splashes and that's something that you can't really tweak with settings you have to just raise the resolution of the sim and then let it run through and just get the detail and it really doesn't cost you anything except for a little bit of extra time so this is a simulation that I made over an orange splash you might have seen this already that I sent at very high resolution and this is just something I quickly put together where I lowered the resolution way lower and you can see that basically you're still getting a very similar effect as far as the speed so this would be perfect to make sure that everything is working properly that the water is shooting far enough and all that but then after I am happy with this I have to go under grid and raise the resolution way up now how high I can't give you a universal number you have to play with this and run the simulation a few times until you find a number that is not taking a year to sim but also that's giving you enough detail but the point is that you have to raise this number for your final simulation to get all the detail otherwise you're gonna end up with these blobs and there's no detail whatsoever and it doesn't look realistic at all if I were to render this out all right so the number three top mistake that I see people make is that their simulation steps per frame are not high enough so this is an example of just water pouring down with one step per frame and because the liquid is moving fast Phoenix is unable to capture all of its movement within one frame so basically you get these gaps and it looks pretty bad now let me show you what it will look like if I go under settings here raise the steps for frame and run the simulation again and see what that looks like all right so with eight steps per frame I'm basically telling Phoenix I want you to simulate the liquid eight times within each frame to make sure that you capture all of the data of the liquid as it's falling down so you can see we basically the result is a much smoother more realistic liquid simulation and depending on how fast your object is you might have to raise this to 12 or even 16 but generally speaking I would stick to four for something like a water tap simulation one where the water is just falling down a straight line like this I would probably raise it to eight but the point is that you almost always have to raise it one is almost never enough unless you're doing slow motion so I would always do minimum of two but at least for my fourth tip for better liquid simulations is slow it down slow motion is your friend generally speaking liquid simulations look much more appealing in slow motion so you can see this is a simulation of a shell and showing the waterfall in slow-mo I think makes it look much more cinematic and cool than if it was in real time so basically in Phoenix I almost always run the simulations at a lower timescale so I would do maybe something like point five for half the speed or even point one for one tenth of the speed which will give you some really nice slow motion and better results and my fifth and final tip is if you're working on liquid Sims that are in real time that are not slow motion then don't forget to turn on motion blur this applies to all of CGI and not just liquid simulations and it's certainly a mistake that I have done myself many many times but don't forget to enable motion more especially in a shot like this it's what allows the droplets to really blend together and make you look a lot more realistic if there was no motion blur you would see these individual sort of streams which would never happen in real life you would never see the drops this sharp especially if the water is moving fast so there's just a quick final tip I hope that you guys found this video helpful if you did as always I would appreciate a thumbs up and also I'm glad that I finally have something to promote at the end of these videos so as you might have seen I finally made a course basically it's a comprehensive Phoenix course for liquid simulations we go over all of these examples that you're seeing right now and basically it's designed to take you from an absolute beginner to being able to set up all of these projects from scratch and all of the project files are included there are a lot of people already enrolled in the course and I appreciate all of you who have already signed up it really means a lot so if you guys like my style of teaching and what I do I would really appreciate if you could check this out again as always don't forget to subscribe us I'll be uploading more thank you so much for watching and I'll see you next time you

Channel: RedefineFX

Views: 43,902

Keywords: vfx tutorial, visual effects, 3ds max tutorial, jesse pitela, redefinefx, phoenix fd tutorial, vray, 3ds max, vray next, phoenix fd, 3d animation, computer graphics, fx artist, fx training, liquid simulation, water simulation, water 3d animation, motion blur, redefine fx, cgi, 3d rendering

Id: 8tDzsiKhzwA

Length: 8min 44sec (524 seconds)

Published: Thu Aug 22 2019