Answers.Body: <p>Yeah, that's a weird thing with the radio waves effect. It seems to be applied after the layer masks, and thus ignores the masks for the layer. This happens for a few effects, particularly ones that generate alpha. It might have something to do with that effect dating back at least to the Bronze Age—you'll have noticed how dog slow it is.</p>
  
  <p>The only way to get the masks to do what you want is to precomp the layer with the effect on it (cut the mask off the layer, then hit <kbd>cnd / ctrl</kbd><kbd>shift</kbd><kbd>c</kbd> and choose <strong>move all properties into new composition</strong>), and then paste the mask on to the precomp in your original composition.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-06-29T16:56:54.783Z
Answers.Text: Yeah, thanks; I was able to lower the opacity afterwards.
Answers.UserDisplayName: DarkRunner
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-06-29T04:58:33.787Z
Answers.LastActivityDate: 2018-06-29T04:58:33.787Z
Answers.UserDisplayName: stib
Body: <p>I created a mask around one part of a radio wave in after effects, to hide that part of the wave. However, when I lowered the opacity of the mask, that left part of the wave doesn't disappear. I've attached a photo below. 
  <a href="https://i.sstatic.net/Difx9.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Difx9.png" alt="enter image description here"></a></p>
  
  <p>I'm using Adobe After Effects 15.1.1. Any help is appreciated. </p>
  
Tags: <after-effects><animation><mask>
Title: Masking Radio Waves in After Effects
UserDisplayName: DarkRunner
ThreadText: # Masking Radio Waves in After Effects
  
  (Asked by: username_0 on 2018-06-28)
  
  I created a mask around one part of a radio wave in after effects, to hide that part of the wave. However, when I lowered the opacity of the mask, that left part of the wave doesn't disappear. I've attached a photo below.
  [![enter image description here](https://i.sstatic.net/Difx9.png)](https://i.sstatic.net/Difx9.png)
  
  I'm using Adobe After Effects 15.1.1. Any help is appreciated.
  
  **Tags:** after-effects, animation, mask
  
  
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  ## 1 answers
  
  ### Answer by username_1 on 2018-06-29. Score: 2 | Accepted answer
  
  Yeah, that's a weird thing with the radio waves effect. It seems to be applied after the layer masks, and thus ignores the masks for the layer. This happens for a few effects, particularly ones that generate alpha. It might have something to do with that effect dating back at least to the Bronze Age—you'll have noticed how dog slow it is.
  
  The only way to get the masks to do what you want is to precomp the layer with the effect on it (cut the mask off the layer, then hit `cnd / ctrl``shift``c` and choose **move all properties into new composition**), and then paste the mask on to the precomp in your original composition.
  
  > **Comments:**
  > **username_0**: Yeah, thanks; I was able to lower the opacity afterwards.  
  
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