• Adobe After Effects Expressions

  Optical Flare Expression not working

  Posted by Jacob Kuhne on February 23, 2016 at 11:31 pm

  Hi,

  I’m creating fireflies for a movie and I want them to turn on when they move up in y position. Each firefly is an optical flare that is parented to a null with a wiggle expression on the position. I haven’t done a lot of in depth work with expressions and can’t seem to crack this one. Could so one please offer some advice or an expression that’s worked for them? Worse comes to worse I’ll do it the old fashioned keyframe way.

  -Jake

  Eduardo Oliveira replied 10 years, 2 months ago 2 Members · 2 Replies
• 2 Replies

• 

  Eduardo Oliveira

  February 24, 2016 at 7:44 pm

  hey, this seems to work:
  change the “target” to your null
  adjust the power variable to suit your needs.

  target=thisComp.layer("Null 1");
power=10;
curv=target.transform.position[1];
oldv=target.transform.position.valueAtTime(time-0.1)[1];
v=oldv-curv;
v*power
• 

  Eduardo Oliveira

  February 24, 2016 at 7:45 pm

  forgot to say – drop this in the “brightness” property of the optical flares layer

Reply to this Discussion! Login or Sign Up