Learn This Trick Before You Animate FIRE

we're going to look at the principles behind creating a fire animation and we're going to build up our understanding of what fire is I'm also going to take you through step by step my process in creating flames as you can see here you can see a few examples of some of the flames that I've recently done in my latest short film which is not currently out yet I had a lot of opportunity to create flames I did them in my own sort of style and I did them in a special style which I felt could complement the story I'll take you through how I do that as well but first of all let's do a rundown of what is fire and how can we better understand it for animation purposes the key principals fire is an exothermic chemical reaction exothermic meaning that it releases heat it also releases light and it can release other products so straight away we're going to talk about the most important topics I feel that there are when talking about fire these are things you've really need to understand if you're going to be animating a flame now convection is the method of heat traveling through liquids and gases fire is also influenced by the behaviors of the air it's surrounded by now before I go into that I'm just going to draw out what a convection current is so that you can see it clearly and let's say this is the source of your heat let's say the substance is contained within this tank this all of this area here is going to be the hottest so that's going to rise but something has to take its place cool air that's from the sides or it doesn't have to be air it can be any any gas or liquid comes in from the side so it will replace it and you can actually see this taking effect in a lot of different flames and in explosions and steam and other things if you look that's not too far off when you look at that you can really see here how a flame might do a similar kind of thing and you can see here how like you know the cold air isn't visible because it's it's not at a level of energy where it can emit light so you can almost see where the flame isn't bright as being like the cold air as a negative space so here you can see this line being defined as like a the cold air coming in so it's very very relevant for animating flames and that's why I've made it the first point this is a flame that's been captured with a long exposure setting on a camera we're able to track the patterns that the flight path of these sparks and see where they go and how they are shaped in the air with this flame here it's very influenced by the wind so there must be a strong wind going through which is why they're all going off to this site but I still thought it was very interesting to be able to see that in in the fourth dimension where you're able to see it over a course of time and see the characteristic of that line of that path we start to see the defining shape of the air that's one example the other thing that I'm going to just show up on screen is a fascinating way of looking at things and it's called Silurian optics it's quite a difficult photographic method where you're able to see light being refracted by heat but at an amplified rate so I won't get into how that's done exactly I will link you to a video a very good video which explains it very well with this we're able to see more of the convection currents than we can with the human eye I find this really fascinating so you can basically see the undercurrents of of air that is usually hidden from our sight so I would really recommend you check out Solaris illyrian optics it might give you a better understanding for how air currents work with effects like this air currents really do shape how the flame behaves another principle is wave motion so a tongue of flame it can be compared to a flag flapping in the wind let's store another diagram here if we have an end let's say it's here and it's like this the area of down here will move first and then everything along that going outwards will be secondary to that action so it could be a cloth it could be a chain or a web or it could be a wave in in the ocean they all sort of follow this wave motion pattern and I think flames do sometimes follow this as well I'll do a very simple one and I will leave the frames on so that you can see by the way I'm animating right now in TV paint but you can apply these to anything any program you want you will be able to take all of these lessons so don't feel like just because you're not using they may be if you're not using TV paint that you won't be missing out in any way you won't they carry across into everything so I've not done that perfectly there it's a little bit clumsy kind of start to see how it it flaps and waves like that that's wave like that is moved along the line so that's a different way of looking at it the thing with the wave motion is it's a bit of an optical illusion it looks like it's moving away from the source but actually it's just moving back and forth in a different way and really what is moving is it's more like the information is moving forward but not the actual substance is you might see that a ripple like this may be quite an acute curve like that starts there and then and then follows up like this and you can really see it go along and up and move onwards like that that's actually how I draw it is I draw the the actual curves moving away but you don't have to draw it like that you can also draw it like a vertical line depending on your style light you know I really struggled with this for a long time until I just forced myself to actually observe how the light behaves in a flame and not what I think it does this is what I got from that the strongest light is generally at the heart of the flame they only create heat at a certain temperature at a high temperature and then after that the ability to emit light sort of falls off that's one thing to consider but then these two principles I think are probably the biggest differences to how you're going to color your flame and I think you will really change your whole outlook on it if you haven't been doing this before so the brightness is strongest in the center and it gets less bright as you go further out the saturation is lowest at the center and generally increases further out this isn't quite as important but the fuel source will define the animation characteris of the flame and it it can be in a big way so different fuel sources release their energy at different rates remember it's a chemical reaction and the reaction happens when you have heat fuel and air so if you take away any of them you don't have the flame sometimes it releases it at a constant rate but sometimes it's not a constant rate and it might ignite more at a certain point in time and then less and this might cause the flame to be bigger at certain stages and then smaller and vary a lot in that some other principles fire behaves differently at different scales something you've got to remember it's a pretty easy one so a bonfire will look vastly different to a candle flickering and so you should consider the scale of your flame it will behave differently depending on the scale flames are affected by gravity and buoyancy and a certain form of surface tension now I put surface tension in inverted commas because I'm not sure if it's actually surface tension it's similar to water in that way like a drop of water behaves very differently to a big bathtub of water my friend said Oh No the flames are simple they're easy all you do is you create two keyframes and you in between those two keyframes and it alternates back and forth so I kind of disagree with that you can create an imitation of a flame by doing that I don't think it will look very realistic and I don't think you will look nearly as appealing as a real flame flames they're complex and they're also seductive and that's partly because of the wave motion a wave motion is very appealing is they're also very complex things they're so complex actually that we can't quite figure them out when we look at them and this creates a lot of appeal in my opinion they're very mysterious and I I like them so if we can't understand a flame but we want to capture the beauty of the flame how do we do this so I'll just show you really quick how you can do that yeah so I kind of adapted this brush from the fact that I've got link in the description for that pack by the way made by my friend but I developed this brush into a sort of quick flame brush it slightly resembles a flame and it looks pretty cool and it lets me draw a flame very quickly and very efficiently which is why I like it what I can do is I can start a flame I'll start with one wave motion so I just created a bunch of keyframes there I'll just add a bit of fog to that [Music] let's just play that back see how that looks okay let's move these apart a bit slow it down make it a bit bigger I'm gonna be keeping all these extra details on the same layer okay so now I'm gonna build off of that you see how I'm gonna build it up in layers we're gonna move things up a bit see what that looks like alright let's add a secondary whip onto the end of this [Music] well that looks like [Music] so you have added I added a secondary ripple onto the end of the previous ripple to just add that extra complexity that I wouldn't have been able to calculate in the moment of drawing that brushstroke because you got to remember like I'm drawing one brushstroke how many calculations can I make in that small amount of time not many so let's add in just some some extra things here at the bottom some flickering of this so some of the flames will be behaving like that they'll be moving kind of erratically and it's because they're just moving so fast that they're moving faster than the frame rate basically let's just do one on this side now just give it a bit more life I'm able to take care of that small aspect of the animation make sure it's flowing make sure it's consistent and everything before moving on to the next little piece of the animation this allows you to build up a complex thing like a flame with relative ease now is this going down I'm going to have that trail break off a little bit okay reach the end of the cycle there I'm gonna make another one right I'm gonna change this one because I've just reviewed it I think you would look better like this a little bit more angled so that we can create another plume from it there now one thing I sort of missed with this that I think I should go back and change with this plume as it's rising up its goes slightly off to the side here and I don't want that because I'm paying attention to the convection current that convection current is right now pushing it completely up the middle so I want it to feel like it's in that stream of hot air so I'm gonna just nudge it here back to where the middle is instead of it going outwards it's a bit too fast for it to be fanning outwards just yet it would fan outwards much closer to the top of the convection current let's just build that out by putting some more things at the at the bottom letting them flicker [Music] let them be a bit erratic you see how that looks yeah quite like that I will just fix some of those frames where the flame isn't filled in here we go it doesn't quite loop around because I haven't really created it to loop but we could easily do that if you wanted to loop this as a flame so it continued so when we're building those details on in the process of building and you know how I've always started at the first frame well instead of building those things on at the first frame start a certain way in maybe half way in and start building them from there we just have this additional flame tone going up the side it's not quite finished when you get to the end and so you carry it on on the first frame again and that helps to just loop the whole thing I could do that a lot more but I haven't really chosen to do that with this flame there are a few things I've missed of course one of them you might point out is that I haven't done the light source properly and in fact on my recent animation which I think I've shown you the clips already I decided to purposefully leave it like this and and that's because I quite like to the style of it I thought it gave a more graphic style is what we were going for there's a good way to save time but with this example I will and I'll show you actually a very quick shortcut that you can do in TV paint one of the great things about having a bitmap is that you do have different blending modes that you can brush in so I found that dodge was quite good so I set the brush to Dodge and I just brought down the opacity quite low so that we could get a good variable of the different levels of intensity it goes through so what you'll see is that it's brightens it up it's in the middle now the only thing about this is it doesn't quite use the saturation correctly if you have it set to dodge and I've yet to find the right blending mode where it behaves just like the light of the flame but I found that dodge was quite similar when you like me and you're creating these productions and you've got to turn them around quick and you've got to make the animation and just make it look good as fast as you can and then send it to them then you end up finding little shortcuts like this and they're not completely realistic but to do add their own sort of appeal I'll just go through like this and build up these the heart of the flame and I would keep this to just that core bit that was the really hot part and I wouldn't really stray into the other areas too much and I thought it created a fairly convincing heart of the flame and with this brush it's it looks pretty nice so you see how quick that was to add it I mean that's how fast we're talking I really had to knock it down with this and create it as fast as possible but if you didn't want to do that I mean there are other ways you could actually paint it in a separate layer towards the middle we bring it closer to the orange spectrum I would say increase the brightness decrease the saturation now with post-production you can tweak these and that's what I would recommend you do what I generally do is I increase the exposure I increase some other things I had to sort of flares and other things tweak the curves bring them up a bit just to make it that much more vivid I would recommend that in After Effects or something similar let's bring it round again to do that core part of the flame now the saturation is really low and the brightness is really high brush is a little bit too soft anyway that's not my strong point anyway so that's what I meant by complexity with technique style so fire can be drawn in a variety of different ways and it can even be animated in a variety of different stars as well what you saw there was like a brush stroke technique so it was very painterly and with the animation it was quite like a ribbon and therefore it was quite seductive quite pleasing on the eye but you can also create one which is really sharp and dangerous looking so in your story eat for it to serve the story I would suggest that you think of your fire as a character it's it aggressive or is it seductive is it comforting or is it alarming and how can you represent this well I just catched out a few different styles of flames yeah more clean edges had a sort of round ball at the bottom that might be good for a torch or with this one a much more aggressive flame with like pointed edges I can already imagine how that might behave in an animation it might be just very few frames that it's looping between and in quite a flickery way and of course this one is more like the flame from a Zippo lighter I hadn't done that with any reference so it probably doesn't look exactly like a Zippo lighter it was kind of foolish of me to not do that so well that one I can imagine it's it's sort of a much more subtle movement and just a gentle moving back and forth maybe whether if someone's breath is nearby maybe that would just cause it to just do that for for a time there are lots of different ways you can do this there isn't a right way to do it really although you know if you follow the principles and you're still able to create your own style of flame then it should look good and it should look convincing and people won't have to say what's that they will know that it's a flame there is even more on this topic that I just don't have time to get into it's a fascinating one all of the elements are really fascinating I'm going to be going through a lot of different elements I might even be creating a course on elements I'll have to see but stay tuned on that check the description because I will go back and edit the description if I do release an online course on the element and animating the elements right now this is just one to see if you guys like these kind of videos tackling effects animation subscribe if you haven't already I bring out regular animation related videos of course thank you very much to my patreon supporters those of you supporting me on patreon you make a real difference to this channel and I love to interact with you on the on the patreon page my patrons can shoot me a message any time and I'll always respond to them and they get access to a whole of these different videos that no one else gets access to so they get a really good deal out of it I think it's just a really good way to support the channel as well so consider doing that if you have spare resources to do so check out animator guilds com it's my website it's got a lot of different resources on it for you lots of different ways that you can learn animation in a quick easy and a thorough way thanks for watching tune in next week when I do a different subject I'll see you in the next video goodbye

Channel: Howard Wimshurst

Views: 75,247

Keywords: animation, learn flash animation, Howard Wimshurst, animatorguild, adobe flash, action, macromedia flash, animation tutorial, how to animate, how to draw, speedpaint, timelapse, how to animate fire, how to animate flames, animating fire, fire animation, advice for animating fire, how to draw fire, how to draw flames

Id: EyWpeexlqp8

Length: 23min 14sec (1394 seconds)

Published: Sat Jan 20 2018