Echo & Onion Skinning + Auto Smears | Effects of After Effects

[Music] the echo effect can be found under the time category and when we apply it to our layer it's going to generate duplicates of that layer offset in time so i went ahead and added some position keyframes on my logo so that it just juts around the screen like this and we can see that duplicate trailing behind now it's also blending it with the original layer so let's take a look at the controls right down at the bottom is the echo operator and it's set to add so that's why this is blending the echo with the original using that add blend mode we can change this to maximum where it's going to prioritize the brightest pixels or minimum where it'll prioritize the darker pixels screen composite in back or composited in front then finally we have blend which is similar to both screen and add it's just subtly different if i switch to add you can see that it's basically the same but you can play around with that to see if it's something that you like now let's look at the actual parameters that control these echoes number of echoes is set to one so we're only getting one duplicate trailing behind if i turn this off and back on we can see that but i could increase this number to however many i want so now we're getting many more trailing behind next we have the echo time which is how offset each one of these duplicates is so it's measured in seconds which is a little confusing but if i increase or decrease this number we're gonna get some craziness just because it is measured in seconds so it's pretty sensitive but if you hold down the control key then it will slow down how quickly this number changes as you click and drag so i can kind of be more precise with it that way i'll undo so it's back to its default for now and then we have starting intensity and decay so the starting intensity is basically just the opacity overall but it's applied to every single instance so these are blending with those opacities it's not just an overall layer opacity i'll reset that back to one and then we have decay which is set to a default of one but if i turn it down each duplicate of my layer is incrementally more transparent so that it's actually fading out so those are all the parameters but what are some things that we can do to make echo pretty useful well one use is turning it into basically an onion skin view of your animation so i'm going to turn my number of echoes down to three and turn the decay up just a little bit and then change the echo operator to composite in front so that the echoes are behind that original logo now in this instance i'm working at 30 frames per second and the echo time is defaulted to what one frame is measured in seconds which is .0333 but what if you're working at 24 frames per second well let's actually just change the composition settings to 24 frames per second and then click ok and now if i advance forward and backward one frame you see that the duplicate frames trailing behind are not locked into that frame rate of 24 frames per second because the echo effect is basing it on a 30 frames per second comp for one frame so i could say one second divided by 24 to get the value of 24 frames per second but that shifts it forward in time because we need to go in a negative value that is another thing you can do with the echo effect which is put the echo forward in time since after effects knows what's happening further along in the timeline it can actually project your echoes forward but to fix that i would just put a minus sign before that value and now if i step forward and backward it's locked into that 24 frames per second so that's how you can quickly get that value and just like that i now have this onion skin view that allows me to look back in time however many frames i want i set it to three but i could turn it down to two or i could increase it up to five it's totally up to you you can really dial in how visible those echoes are with that decay value now one other really fun way of using the echo effect is generating speed smears which is a technique used in traditional hand hand-drawn animation to basically simulate motion blur or to imply really fast movement so i'm going to reset the effect and we're going to be using a few expressions to make this a lot easier to work with first of all i need a lot of echoes so i'm just going to crank that up to say 15 to start and i'm going to change the echo operator to maximum for now now these echoes are too far spread out i don't want to see a trail that's this wide in fact i don't even want to see any gaps between the echoes so i need to get a much smaller number right here so i'm going to hold down control click and drag and that's really just too sensitive because even right there that's not enough i don't want to be able to see all these gaps between the duplicates so what i'm going to do is double click on echo time which will bring up that property in my timeline and i'm going to add an expression so i'll alter option click on that stopwatch and type value divided by 100 and this is effectively going to make that value 100 times more sensitive so if i click and drag now and this is without the control key held down it's much easier to align that if i hold down the control key i can be even more precise so i'm just going to make something that looks a little bit like that this is a pretty good smear frame and because i have the echo operator set to maximum the brighter parts of my layers of all of the duplicates are being prioritized and stacked on top if i switch it to minimum it's going to reverse it like that i like the way that looks so i'm going to leave it like that for now so if i play this back we have these nice smears happening but i think it's a little too heavy-handed we're seeing it even when it's not moving that fast and i'd rather just see it when it's moving maybe this fast or faster so how can we tell after effects to only show this smear if it's moving that quickly well i'm going to make a new text layer really quick and i won't even type anything in it i'll just go ahead and twirl it open and under the source text property i'm going to add an expression then i'm going to use the expression pick whip to grab my logo layer and then type in dot transform dot position dot speed this is now going to tell me the speed of that layer for every single frame in my animation now that's giving me a ton of decimal points just ignore that for now at the fastest moving part right about here where i want to see the smears it's traveling at a velocity of 2200 pixels per second so now i know my range basically of speed that i want this mirror to appear in i can implement that into my echo effect so i'm going to grab the number of echoes double click on that to bring it up down here and we're going to add a similar expression to this so alt or option click on it to add an expression and i'll give myself some more room so we can see this clearly and i'm going to write an if else expression which i have a dedicated tutorial to you can click the card above right now to view that but what we're going to write is if and then an open parenthesis and since we're on the logo layer the actual layer that this effect is applied to all i have to say is transform dot position dot speed to target the speed of the layer and then i'll do a greater than symbol meaning if the speed is greater than and then we'll say 2200 because that's roughly what the speed was at that frame then i'll go outside the parentheses and do an open curly bracket drop down and just type the word value so what this means so far is if this layer is moving faster than 2200 pixels per second then we want the number of echoes to be whatever we've typed in right here but then i need to go down past this closing curly bracket that after effects generated for me and say else another open curly bracket drop down and say zero and after effects again made a closing curly bracket for me so what we're saying is if the speed of this layer is greater than 2200 pixels per second make this value whatever i've typed in here otherwise if it's not going that fast then don't have any echoes we don't want to see anything but the original logo so i'll apply that and then just back up one frame where my speed is less than 2200 pixels and my echoes have completely vanished so if i play this back again now we're only seeing those smears when it's traveling at a speed of over 2200 pixels and i think that looks pretty decent now we can control the look of these smears really easily just by increasing or decreasing the number of echoes so if i increase this my smear will be much longer or if i decrease it it will be less but what if you want to adjust that threshold without having to go into the expression every time and adjusting this 2200 number well we can make this a lot more flexible and easier to edit if we just add a slider so if i go up to effect expression controls slider control i'll rename this speed threshold and if we edit this effect and change where we had 2200 as a hard coded value and use the expression pick whip to choose the slider value and then apply that expression now i can use this slider value to control the threshold for that speed cut off so if i go to something higher than what it currently is we're not going to see any echoes and the smears are only going to happen on the fastest part of our motion which is right here so with a few simple expressions we can create this completely customizable smear generator using the echo effect hey thanks for watching if you enjoyed this tutorial then check out the other ones here on my youtube channel and if you like my teaching style then definitely check out my longer form content on skillshare and school of motion and if you want to support more tutorials like this one check out my patreon you can find links for all that stuff in the description of this video [Music]

Channel: Jake In Motion

Views: 38,504

Keywords: After Effects, Animation, Motion Graphics, Mograph, Motion Design, Tutorial, Adobe, Adobe After Effects

Id: N2qxF8V57FE

Length: 9min 34sec (574 seconds)

Published: Tue Aug 31 2021