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How would you achieve this effect?

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Max HamworthHow would you achieve this effect?
by on Jul 17, 2015 at 3:16:34 pm

It looks advanced, although I believe they are a few paths with some distort effect on them.



In this one you can see it at a lower value.


How would you do it?

Thanks!


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Kevin CampRe: How would you achieve this effect?
by on Jul 17, 2015 at 9:19:05 pm
Last Edited By Kevin Camp on Jul 17, 2015 at 9:22:15 pm

you could create something similar to the first example with the write-on effect, and simply add an expression like this to the brush position property:

freq = 5; // how quickly the values are changed in times/sec
amount = 200; // in pixels
wiggle(freq, amount)


modifying freq and amount will change the amount of 'scribble'

the other could use an expression too, but with a sine or cosine function worked into it.

-----edit-------

i should have added to reduce the brush spacing value to get something closer to a line than a string of dots.


Kevin Camp
Art Director
KCPQ, KZJO & KRCW


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Kevin CampRe: How would you achieve this effect?
by on Jul 17, 2015 at 11:32:07 pm

you can get better results if you use a particle system to leave trail of particles...

if you happen to have trapcode's particular (from red giant), it is well suited for these, but you can do it with the stock particle systems too.

for stock effects, try this:

first create a null (layer new null) and add the previous expression to the position property (we'll use expressions to track that null).

then create a new solid and add particle world.

to link the producer to the null, you'll use the following expressions (particle world has an unusual coordinate unit system, this would be much easier in particular):

position x:
target = thisComp.layer("Null 1"); // change 'Null 1' to you null layer if needed
(target.position[0]-(thisComp.width/2))/width


position y:
target = thisComp.layer("Null 1"); // change 'Null 1' to you null layer if needed
(target.position[1]-(thisComp.height/2))/width


position z:
target = thisComp.layer("Null 1"); // change 'Null 1' to you null layer if needed
target.position[2]/width


also set the producer radius' to 0s.

in physics, set the velocity and gravity to 0, and in particle, set the 'type' to added sphere, and the birth and death size to 0.100.

at this point it should be drawing a scabbily line (or string of dots).

to refine it, crank up the birthrate to 300 or more and increase the longevity to 10 or more. in particle settings set size variation to 0 and lower the max opacity to about 1. twirl down the opacity map and make it straight across the top (remove the bell-curve-like ends by clicking in the graph and dragging across the top edge). you can also set the color as needed.

this should get pretty close. the line may seem like a bunch of short straight segments. this is due to the effect not being abel to do sub frame sampling in it's calculations. to smooth it out, go to the comp settings and set the frame rate to 99, and then add that comp to a new comp with a normal frame rate and the lines will be smoother.

you can make it more interesting by going back into the physics settings and increasing the inherent velocity a bit (try 1, and go from there), and you might add a little resistance, about .1 or so depending the inherent velocity value. this will make the line expand as the particles take some velocity from the producer.

you could also add the glow effect and drop the threshold down and increase the intensity to give it a nice glow.

Kevin Camp
Art Director
KCPQ, KZJO & KRCW


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Max HamworthRe: How would you achieve this effect?
by on Jul 18, 2015 at 9:19:16 am
Last Edited By Max Hamworth on Jul 18, 2015 at 9:26:45 am

Thank you for looking at this for me Kevin.
- The first wiggle expression with the write on effect is close just a bit simple. EDIT: its quite neat, though the write on effect is a limited, if i increase the number of 500px it becomes dots even with the brush spaces at lowest.

- The second expression in with the first expression on Null 1, combined with particular got me nowhere. AE claim bad syntax in the Z position, even without the position. Got nothing out of the ordinary just the basic particular emitter doing what you'd expect on first application.

What did I miss? Thanks


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Kevin CampRe: How would you achieve this effect?
by on Jul 18, 2015 at 2:26:17 pm

Write-on is very easy, but limited. If you want to increase the amount (size) of movement, you'll need to decrease the frequency ( thus decreasing the speed) to get the dots to form a line. You could then take that comp into another comp and speed it up if needed.

If you use particular, create a light and name it "Emitter". Partcle color will be derived from light color, so you can set that now too. Then Add the first wiggle expression to that light's position.

Then in particular set emitter type to light. The emitter will now track the light.

A lot of the same properties as partcle world will need to be adjusted, but some of the properties have different names and of the values will be different, birth rate in particular will be much higher. I believe particular will handle the sub-frame sampling so you shouldn't need to resort to the frame rate trick.

In particular you can set blending modes for the particles, setting them to add may give it more of a glowing, light streak feel.

Once you have settings that are working, you can duplicate the light an set it to a different color and particular will automatically add it as an emitter and you'll have two different colored light streaks in the same . You can do that multiple times, it's a pretty neat feature, I don't know another particle system that can do that.

Particular also has turbulent field settings in the physics settings, which could be pretty cool with this effect.

Kevin Camp
Art Director
KCPQ, KZJO & KRCW


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