How to Create a Blinking Red Dot?

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How to Create a Blinking Red Dot?

Postby socialmohshi on 07/10/2015, 2:37 am

Hello guys!
This is my first post to the forums, so please excuse me if I have posted this topic in the wrong channel.

I am a filmmaker, who is experimenting with VFX for the first time, so I'm absolutely clueless about how these things work.

Learning softwares has not been a problem for me, but the need to use After Effects or any other VFX related software has not risen in my filmmaking days, until today.

So this might be the most amateur post out there, but I wish to ask the community for help, since I wish to learn everything about VFX from scratch.

The need-
I wish to create a blinking red light that is shaped in the form of a dot.

After creating it, I wish to place it on all the areas I have pasted a green/blue dot on certain accessories to replace them with the red blinking light.

It would be great if someone could help point me in the right direction to execute this.

Looking forward to the response.

Thank you Videocopilot community.

= )
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Re: How to Create a Blinking Red Dot?

Postby gregalan on 07/10/2015, 8:28 pm

Hi socialmohshi, welcome. Yours is a hard question to answer as there are many ways to do what you want to do but all require some knowledge of After Effects.
If you haven't any of the basics then I would recommend you start with these tutorials - which are very old but they are quick and will give you some idea of what you are doing:

Once you've done that and to answer your question, the simplest way (though probably not the best way, depending on your footage and the look you want to achieve) could be this:
Duplicate your footage in the timeline
Pre-compose the top layer
In the pre-composition Key out the green/blue dots on your footage
Add a red solid under your keyed out footage (the green/blue dots will now be red)
Add the Stylize/Strobe Light Effect to your red solid - set the strobe color to very dark red, set the duration and period to make it flash as quickly as you want it to.
Add the Color Correction/Tint effect to the video layer in the pre-composition - Map Black to bright green, then use the Map White color picker and select the bright green sample above it (you will now have a solid bright green background with only the red dots)
In your original composition Key out the bright green, then add the Stylize/Glow effect to that same layer - maybe increase the Glow Radius etc.

That's about the clearest/simplest I could suggest without getting into track mattes etc.

If that isn't the look you want you may have to get into tracking the dots and parenting 3D layers to them which is another more complex story.
For more detailed and comprehensive tutorials I personally find Andrew Devis extremely good: ... devis.html
And there are also more choices: ... r-eff.html
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Re: How to Create a Blinking Red Dot?

Postby star+circle on 07/11/2015, 3:44 am

Yes, definitely basics first, otherwise it will be next to impossible to figure out why something seemingly doesn't work.

If you have moving-camera footage, the ideal way to do what you are trying to do is with the 3D camera tracker: ... a-tracker/

But that's definitely several steps beyond basics. You will have to understand 2D and 3D layers, the timeline, keyframes, the AE camera, tracking etc. to be able to effectively use such tools.
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Re: How to Create a Blinking Red Dot?

Postby lulesu on 07/14/2015, 9:07 am

This is a very wide question you should provide at least an image with such kind of light you want to create. for me i would simply create a red cycle shape and animate its opacity to appear and disappear gradually. In addition to that i will feather the sphere a little bit and add glow, so it will look like a red light which is blinking. to go further i will add grid on top to look like the light.
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