How To Composite Water Blast VFX | Nuke Tutorial

hello everyone dunasa here with action vfx in today's video we are going to learn how to do waterblast compositing in the foundries new this tutorial will be more introductory level on learning the basics of compositing and we will be using our waterblast stock footage from our water blasts collection if you want to learn the absolute introduction to nuke you can check out our intro to nuke tutorial link on the description below anyway without further ado let's begin okay so this is what we are going to do i'm going to give you a quick overview before we start over so here of course we have our final render at the bottom and we have our merge node here that is merging an element which is our water blast and the back plate which is our back plate so if we go up the b spine here we have our back plate and then there's also a tracker node where i did some motion tracking on the background to put our water so the tracker is connected to a transform node at the end here and in this branch of course we have a water blast and reflection and if we go up here this is our water blast and basically here i did some retiming and then i move it and then i split the branch into two one is for creating reflection and the other one is just the water blast and then i merged them together and then did some defocus and then masking and then of course we have the motion track transform here to help our water blast to track into the shot and then it's merged into the plate so let's begin our compositing so i want to select these two here our water blast and our backplate copy it and then let's move to a space here paste it and then we also want to move our viewer to there so now we can begin our compositing okay so here we have our backplate and also our water blast element so the first thing you want to do before we start with our compositing is to set up the project settings so press s to bring our project settings let's scroll down and here we want to make sure we have our project settings set up correctly which i have already done from the previous project so here i have my frame range from 0 to 75 and i have my frame rate which is 23.976 or around 24 frames per second which is the same as the frame rate of our back plate here and then also the size format we have 1920 by 1080 also just like our backplate so let's close this and start compositing so the first thing to do in our compositing process is to figure out the main premise of the shot and then iron out the details so the main premise or the main spine of this project is we want to have the water on top of our back plate so let's first establish that press m to bring a merge node and then drag the merge node to between our viewer and our backplate and then set this a input to our water blast so now if we go here we will see that our water blast which is on the a input is on top or over the b input which is the back plate so here i don't like seeing this kind of diagonal streamline so what i like to do is hold ctrl and then click here and drag it and here we have this dot which just helps break the diagonal line and it also gave us basically a pit stop to look at the stream a which is our water before it enters the merge node this is just my personal workflow so if you don't do this it's not going to affect the final result in any way okay so here we can see that our water blast has a completely different resolution than the back plate which is not a problem because the resulting format size of a merge will always follow the one on the b stream so it is not a problem for our water blast to have a completely different format however i personally like to have my stuff on the a stream here to already have a matching format before it enters the merge it just makes things a bit neater for me so i want to do that let's get a format and put it here there we go so now our waterblast resolution has been changed to the same as our project settings which is the same as our back plate so here i want to change the resize type to fit so now that our water blast is centered and then let's go to our merge and then i want to position the water blast to around here so let's get a transform node drag it here and then i want to hold ctrl and select the controller here and then drag it to the bottom of the water blast so now our pivot has been changed and we can then move it here there we go okay so let's close our transform and see what we have okay so the first thing that is very noticeable of course is our water blast is not tracking into the shot and also the water blast is moving in slow motion so let's fix that we want to fix the tracking first so there isn't a lot of parallax going on from the movement of the camera so we don't need to do a 3d tracking we can just do a simple 2d tracking using the tracker node and then we want to connect it to our backplate there we go then let's look through here so now what we want to do is we want to create two points because we want to track the position and the rotation first let's create the first one and then i want to track around this area of the bridge because we have a great contrast there there we go and then i want to create another one and then i want to put it on that black dot on the background there we go and in here we have our track 1 and track 2 on our tracker panel and we want to turn on the t for translate and also r for rotation because we want to track both of those properties so hold them and start tracking forward and then backwards and there we go we have two trackers that are tracking our shot so in the tracker panel what you can do is you can go to here to our transform panel and we can set a reference frame for the tracker however for this shot the camera movement is quite minuscule so having an exact reference frame wouldn't matter as much so i just left it as it is so now that we have our point tracks let's convert this into animated transform data so with those two selected let's go here on export we have so many options and we want to choose the transform match move we have two we have transfer match move and transform match move baked the transform match move will create a transform node with its animation directly linked to the two points that we have on this node whereas the transform match move baked it will create transform node with its animation baked into the node itself so it's not connected you can use either one but i want to use the the one that is not big so click and create and here we have our transform with animation that is directly connected to the tracker so whatever we are doing to these two trackers it will update the position on this transform match move so let's input it to our water blast and go back here to our merge node and see what we have so far perfect our water is now following the shot okay so the next thing we're going to do is fix the timing of our water blast so the reason why our water blast is moving really slow compared to the plate is because we have our project settings set up to 23.9 or around 24 frames per second whereas our water blast if we check the metadata here you will see that our water blast is moving at around 59 frames per second for around 60 frames per second and nuke doesn't automatically interpolate our water blast so because it has around 60 frames per second running on around 24 frames per second playback our water blast is now moving at the slower rate or to be exact around 2.5 slower than it should be that is because 60 divided by 24 is 2.5 so let's speed up our water blast to fit our project and we will do that using a node called chronos so let's drag our chronos here so chronos is a retiming node available for nuke x and nuke studio so in our kronos let's make sure we have our input range the same as our read node for the water blast so let's go in here and get the final frame from the reap node there we go and then for the output speed we want to put in the number that i mentioned which is 2.5 and now we have made our 60 frames per second footage to play back in our 24 frames per second project however the actual water blast itself was actually shot in 96 frames per second but delivered on a 60 frames per second file so right now it is still slower than its real life speed so if you are looking to get the actual speed of the water blast as it was shot you need to divide 96 which is the original frame rate of the water blasts as they were shot by your project frame rate and then use that number for the speedup factor so if your project is 30 frames per second you want to speed your footage up by 3.2 and if you have 24 frames per second like what we have here you want to go with 4. however for this tutorial i already like where we had with 2.5 but maybe just a little bit faster so i'll go with something like 2.7 great now because our water is shot in high frame rate we don't have a lot of motion blur so let's add motion blur so to do that we want to first consult to the back plate and look at the motion blur of the real water that we have here so here we can see what our motion blur looks like that's quite a lot of motion blur but not too much okay so let's go back to our water here and then go to the shutter and then add shutter samples to 10 and then our short time let's set it to two there we go so now we have motion blur on our water so we have fixed the timing and the tracking let's start developing the look of the water the first thing i want to do is to add reflection at the bottom so let's expand our script a little bit more so we can add more stuff okay so now what i want to do is i want to add a dot below our transform here so control click and then let's create a transform again and then connect it to our dot so in this node branch we will develop our reflection and then we will comp it back into the main stream let's look at our transform number three here and then we're gonna hold ctrl again on the controller and put it at the bottom of our water and then we're gonna go to scale and we are going to click this two symbol to separate the width and the height and then we want to set -1 on the height boom so now we have our water blast being flipped so this will be our reflection so then let's add some reflection blur to our water here let's get a note called directional blur or deer blur drag it here there we go and then we are going to set the blur type to linear and the blur angle to 180 there we go and then let's set the blue length and we have this really cool directional blur great so now what we want to do next is we want to add some noise displacement on our reflection because if we see on our plate here we see on here how the bridge has this ripple noise on its reflection so we want to do the same thing to our water blast so let's go back here to do displacement or distortion in nuke we will need a node called i distort and let's drag it here there we go so if you use after effects you know that in order to do a displacement effects the effects need to have a reference layer to drive what the distortion look like i distort is similar but it needs our reference in a form of uv channel that is embedded on the input stream and we currently don't have a uv channel on our stream we currently only have red green blue and alpha or rgba so we want to create a noise map and then add it as a new channel on the stream so let's create the noise press tab bring the noise node look through it here so let's play around with our noise here so let's play with our size again click number two here and we have our x and y size being separated we're going to change this to 300 and the y to 13 there we go and then we want to create some animation on the noise so we want to animate the z so let's go to the first frame which is frame 0 and then on here we're going to right click and set key so now we added a keyframe to the timeline which you can see on the dope sheet here and then let's go to the final frame which is frame 75 and let's say change the z to three and it will added another keyframe so now our noise is animating so we have our noise let's convert this into a uv channel on the stream so to do that we will use a node called copy let's drag it here and then set the a to the noise there we go so let's look at the copy here so what copy does is it transfers a channel from the a input to the b input okay so i distort needs uv channel which is a coordinate channel represented by u for horizontal and v for vertical and because our noise only consists of rgba color channels we're gonna convert one of them to uv and since our noise is black and white we can just pick any color let's say red and then we are going to change it to a brand new channel let's call it noise map so because we want this noise map to drive the distortion horizontally let's designate our noise map to the u channel of the uv so press dot and u okay create a new layer there we go so now we have our noise map as a channel and then let's go to i distort here let's look for our water blast there we go click here and on this uv channel of our eye distort let's select our noise map there we go and then on the uv scale we are going to increase it really big so now our water blast is being distorted horizontally if we set the noise map as noise dot v it would distort vertically so now we have our reflection let's finally merge this with the main water blast which is this so let's press m to bring our merge bring it here and then we want to put the a to the reflection so let's look here and this is what we have now we are currently having our reflection which is a on top of our water blast which is the b which i don't want i want the reflection to be at the bottom of the water blast so we can do that by just switching the a and the b input by just pressing shift x or let's undo instead of over we want to change it to the opposite of over which is under so now it's not very noticeable here because of the nature of the elements now i have the a under the b so now the reflection is the one at the bottom without switching the input so now let's look at our main merge here and let's zoom in a little bit here i want to move the reflection to the top just a nudge there we go to close that dark gap that we had earlier and then let's make the reflection to be a bit more faint so reduce the opacity and we can actually do that by going to the merge and reduce the mix or you can get a multiply node actually i don't like having a node going horizontal like that so let's move this to the bottom and there we go and then let's reduce the value and we have our reflection so let's play and see what we have awesome so now let's start color correcting our water blast so something to keep in mind when color connecting elements in nuke is pre-multiplication our elements usually already have multiplied with its alpha channel that is what gave the elements a transparent background because of that sometimes when we do color correction the edges of our elements get affected by the color change so we don't want that what we want is to separate our alpha or unmold before color correcting so let's go here and get on primo so here we can see our water is now glitching really weirdly so what's happening is that we have separated the alpha of this water blast from the color so now we only have the color information and then we want to add a color correction node for me i want to add a grade so press g and then put it here so here we will do the color correction and then after the color connection we will bring back the alpha using premolt so it is actually best to test this with a solid cg render because it has more clear off edges to demonstrate this concept but it is always a good habit to do this on premolt and play mode when doing color correction so that way when we color correct here we will not affect the edges of the elements so here to do our color collection let's go to our final merge and here let's start color correcting so our footage here is a bit blown out which may be difficult to do color correction in so let's reduce the gamma and then let's bring the f-stop there we go so this changing this gamma and f-stop will not affect the final shot in any way this is just for preview while we're composing now we want to start color correcting so here we can see that the real water splashes is very bright and our water splash is not bright so i want to go to the white point and go to the left there we go so here i want to make the water splashed a bit bluish just like this water but not too blue so to play around with the red green and blue i'm gonna go to this circle here and hold ctrl and click and we will have this color swatch so i will turn this a bit blue okay and you can also go to this boxes here using the arrow on your keyboard and just manually dial in your number okay let's play our footage okay pretty good so let's normalize our gamma and our f-stop again so the next thing we are going to do is we want to add a bit of camera blur on our water blast and if we watch our backplate so let's look at the backplate and we scrub through we will see that the shot is getting blurry as time goes so we want to mimic that let's animate a blur on our water blast so let's go back to this merge here and let's get a defocus node okay and then let's put it here and then we want to do some organizing so on our defocus let's do some animation i'm going to go to around frame 30 which is when it's not too blurry and go to the defocus and right click set key and then we're gonna go to say frame here when it's a bit more blurry and we're gonna increase it to two there we go so now we have the blurriness animated okay so the next thing we want to do is i want to play around with the reflection again for a little bit so here we see that reflection on this bridge is very opaque so let's mimic that we actually have our reflection a bit too soft so let's increase there we go and then we also want to mask out the edges for our reflection a little bit here around this area so let's mask that up so let's get the router node and drag it here and we want to draw around that area that we want to cut out so one thing to keep in mind when you are creating a mask on the router node is that you created a keyframe automatically so if we go to another frame and you accidentally move it it would animate so we want to make sure to remember which frame that you draw your mask on or you can just delete the key and we no longer have the key but of course when we move it again it would create another one so just keep that in mind okay so now we have created a mask on the rotor node let's connect it to our stream so press m and bring our merge here there we go and connected to our roto and we have this dark blotch because what we did is just we select the shape that we just created and just over it on our stream which is not what we want to do what we want is to switch this to mask however when we switch it to mask what happened is the rotomask that we just created is actually isolating that area instead of excluding it so to invert our mask we can just use a stencil instead of mask or keep the mask and get an infrared note and then put it in between the roto node and the merge mask there we go now let's fix our mask a little bit another thing about the road node in nuke is that we can pull a feather at the edge there there we go now we have feather on our mask okay so we have everything set up we have the reflection we have the water now the two last thing i want to do is first i want to offset the water blast because now the water blast happens very early i want to actually offset the timing so it starts a bit later on the shot so to do that we can of course go to the large blaster and just play with the frame settings but we're not going to do that what we want is to use a node called time offset so time offset as the name says it will offset the time of whatever that is inputted on it so we want to put it just below the clonus because if we put it on top of the chronos it would mess up with the timing because we already have the input range on the chronos so we want to make sure to have the time offset below the chronos so click here and we can set the offset how many frames we want to offset it or we can just go to dope sheet and let's zoom here and just drag the timeline off the time offset there we go so now we have offset the time and then i want to get rid of this extra bounding box that we have this extra bounding box came from our water blast assets because we transform it around so it creates this extra bounding box which isn't really a problem in this project but if you are working on a big project with a lot of nodes this extra bounding box could sometimes slow down your project so we want to cut them off because we don't need those extra data so let's get reformat put it just below our transform match move and boom we have got rid of the extra bounding box and this is what we have another extra thing i want to show you is backdrop and sticky notes these tools are great to help you organize your script backdrops allow you to select an entire group of nodes together and you can name it or change its color if you want to detach a backdrop from a node you can hold ctrl and remove it and another organizing tools that you can use is sticky notes which is super helpful for adding notes or labels to your script and that was a tutorial on basic compositing using our water blast collection in nuke let us know if you have any new tips and tricks that you'd like to share and as always if you want to purchase the asset that i used in this tutorial you can check out our website at actionvfx.com at actionvfx we provide high quality vfx assets for your vfx needs we have fire explosions energy and many many others you can also sign up for our action vfx subscription starting at the low cost of 14.99 a month this is the most affordable way to access our library and you can cancel anytime no contract thank you so much for watching let us know in the comment section below what kind of tutorials that you'd like to see next and see you next time bye you

Channel: ActionVFX

Views: 9,985

Keywords: actionvfx, nuke, beginner, introduction, tutorial, compositing, water blasts

Id: ooad43Lg4MA

Length: 27min 55sec (1675 seconds)

Published: Thu Sep 30 2021