Create a Grenade Explosion - AFTER EFFECTS

Today I'm going to be showing how you can create a grenade explosion using Adobe After Effects. I'm also going to be showing where you can find the VFX elements that I used for this effect. For a lot of the effects that I create, I love using assets from ActionVFX. They have so many great elements like fire, smoke, explosions, gun effects, you name it. All of the elements that I used for this effect I found on ActionVFX, and right now they're having a crazy good Black Friday sale until December 3rd. All VFX elements in their library are 50% off. Also, all annual subscription plans purchased during the sale receive two times the amount of monthly elements. So if a plan gives you 30 elements a month, you now get 60 elements a month. And a really cool thing that they're doing is if you renew your annual plan next year, you continue getting double the elements. So right now is the perfect time to get you some high quality effect assets for a great price. Again, the sale is running until December 3rd. I'll leave a link down in the description where you can check out ActionVFX. But alright guys, now let's jump into how you can create today's effect. So that clip that you just saw was a short action scene for a film contest that I entered a few years ago. The idea was a guy has a sort of a magic bag that can conjure up anything that it wants to. So that's just a little bit of an explanation so you know what you just saw. But we're not talking about that today. We're going to be talking about the grenade explosion at the end. For the footage, it's pretty simple. My friend Alex here, who played the main character, throws a prop grenade at my other friend Robert, who played a bad guy, and he jumps away like the grenade exploded. Then I brought that footage into After Effects and created the effect. In After Effects, first thing I did was make sure the resolution of my project was set to full quality. This is important so After Effects has more information in the footage to get an accurate track. Then I right-clicked the footage layer, hit track and stabilize, and selected track motion. For my footage, I only had to make sure the position box was checked in the tracker tab since the scale and rotation of my shot didn't change. Then I set the tracker point to be on a leaf on the ground that stood out pretty good from the grass around it. Then I came over and selected analyze forward. After that was done tracking, I came up to layer and created a new null object. In the tracker tab, I selected edit target and selected that null object and hit OK. Then hit apply and made sure apply dimensions was set to X and Y. Now to create the grenade explosion, I used four different assets from Action VFX. The first one was from their Aerial Explosions volume 2 pack and was Air Explosion 19. I used this to create a small flash ignition for when the grenade first explodes. For the second asset, I used one from their Dust Waves volume 2 pack and this one was called Dust Front 6. This was to create a dust wave being created from the explosion. And then for the main explosion, I used two different assets. One was from the Dust Explosions pack and I used Dust Explosion 8. And the other one was from the Dirt Blasts pack and I used Dirt Blast 5. Now you can use whatever variation of assets that you want. I'm just showing you which ones I used. Something I did was watch some videos of real grenades exploding for reference. And what I found was a real grenade explosion is pretty much just an explosion of dirt and dust. So next, I started bringing those assets into my composition. The first one I brought in was the Aerial Explosion. First thing I did was right-click that layer, went to Time, Time Stretch, and changed the amount to 60. This was just to speed up the explosion some. Then I trimmed this to last about 4 frames since I only wanted it to be the initial spark that starts the explosion. After that, I parented this to the null object by selecting the pick whip here and clicking and dragging it to the null. Then I scaled to position this explosion to where I wanted it in my scene. I placed it over the grenade and had it begin right when I wanted the grenade to start exploding. Next, I brought in the Dust Explosion asset and stacked it on top of the Aerial Explosion layer. I went to Time Stretch for this layer as well and changed it to 40. After that, I parented this explosion to the null object and then scaled and positioned it to where I wanted it. I also timed this layer to start a few frames after the Aerial Explosion layer starts. On this Dust Explosion asset, there was an area on the bottom where you could see the ground, so I needed to get rid of it. To do that, I selected the dust layer, hit G on the keyboard to bring up the pen tool, and created a mask around the Dust Explosion. After I was done creating the mask, I hit F on the keyboard to bring up the mask feather and increased the amount to 50. Now you see how the Dust Explosion is going in front of this wall here? Well, it should be going behind it. To fix that, I needed to create a mask on my main footage layer. So I duplicated that layer by selecting it and hitting Ctrl D, then brought that duplicated layer up to the top of the composition. After that, I created a mask on this top footage layer that was around the wall and roof. Then I hit M on the keyboard to bring up the mask path, selected the stopwatch, and then went through adjusting the mask to stay around the wall and the roof. I only had to do this for the part where the grenade explosion was. I also increased the mask feather on this to 15. Now you can see that the Dust Explosion fits into the scene more and goes behind the wall. Next thing I needed to do was create a shadow here on the ground that the Dust Explosion would be casting. So I duplicated the Dust Explosion layer and renamed this bottom layer Shadow. Then I added the radial shadow effect to this layer. In the effect controls, I changed the opacity to 30%, softness to 100, and selected for it to be shadow only. Then I adjusted the rotation and position for this layer so it lined up underneath the main Dust Explosion and looked like its shadow. My shadow had a hard line here at the base of it, so I adjusted the light source settings until it was gone. I just had to mess around with these a bit until I couldn't see that line anymore. I also adjusted the mask on the shadow layer so that it fits into the space between the wall and the tree. Now when I play that back, you can see the Dust Explosion looks like it's casting a shadow on the ground. After that, I added the Dirt Blast asset to the composition and layered it underneath the Dust Explosion layers. I brought this element in to help add some texture and depth to the effect. These stock footage elements can look a little flat sometimes on their own, so it's good to combine a few of them together to make them feel a bit more three-dimensional. For this Dirt Blast asset, I pretty much did all the same steps that I did for the Dust Explosion layer, except creating a shadow for it, because the Dust Explosion shadow will act as the shadow for the entire explosion. Then I also had this element start a few frames after the Dust Explosion. Next thing I did was add the Dust Wave asset to the composition and layered it underneath all of the asset layers. This asset was on a black background, so to get rid of that, I changed the blend mode to Screen. If you don't see the blend mode option, you can come down here and select Toggle Switches and Modes to bring it up. Then again, I went through the same steps, sped up the clip, parented it to the null object, and adjusted the scale and position to fit into the scene. I also changed the opacity on this layer to 50%. You can bring up the opacity by hitting T on the keyboard. Now the explosion has a dust wave coming off of it. Also, I added the CC Force Motion Blur effect to all the VFX assets and increased the Motion Blur samples to 5. I just wanted a little bit more Motion Blur to them. I felt like they were a bit too sharp. And then after all of that, I added in one more finishing touch that really ties the entire effect together. This was adding some camera shake for when the explosion goes off. So to add this, I selected all of the layers in the comp, right-clicked, and selected Precompose. Then in that new composition, I increased the scale of the layer to 110. This is so there's some extra room to add the camera shake. Then I went to where the grenade starts exploding and split the layer at this point. I selected the part that has the grenade explosion and brought up its position. Then I held down Alt on the keyboard while I selected the stopwatch, and then I was able to type in an expression. So I typed in the expression, wiggle, open parentheses, 5, comma, 150, close parentheses. Now when I play that back, you can see there's some camera shake for the explosion. This is what the effect looks like with the camera shake and then without it. It really adds the feeling like it's a violent explosion with some power to it. And then there you go, guys. That's it for the effect. I just added in some color grading and sound effects and had the final result.