AE Expression to change a single value every X seconds.

Hello there,

I've been trying to write a simple expression that changes a single value, in this particular case the 'Glow Intensity' in the 'Glow' effect, every couple of seconds.

I'm failing miserably and I can't find what I desire on the numerous websites i've searched.

Can anybody help me?

Here's a bit more detail:

I have a sci-fi type corporate company (fictional) , and I've done a simple animated sting of the company logo, and within the logo there are some subtle details that I've applied the glow effect to. I just want the glow to 'throb' every few seconds, giving it a bit of life.

So, the main value is 1, but then every couple of seconds it smoothly (but quickly) increases to 2 (or 3, or whatever), then returns to 1 with a gentle decay. Imagine the red eye of HAL in 2001 Space Odyssey.

I'd be really grateful if somebody could help me, as I'm sure it would be a very useful expression that I could apply to numerous other things in future.

I know I could achieve the desired result by simply key-framing the value, but I'd really like to avoid that as it seems like a bit of a cop-out.

Thanks in advance for your help.

Kind regards,

James.

Senior Editor
ichi london