Viewing Mask Effects and Background Video Simulataneously

[Guest]

Okay, I admit it.  I"m buffalo'd.

I see that others can create a mask on a layer, view the mask, any adjustments you make to the mask (like feathering), and see the results at the same time.  I can't figure out how that is done.

I admit this is basic, but I'm not getting it.  Somehow I think that I should be able to add a mask to a layer, such as some kind of footage, could be any footage.  I know by default the mask cuts out the video showing only the video inside the mask (this I get and can do), but I also see through some online training that some can display the mask and ALL of the background video at the same time.

I figured out that I can do this via Pre-Comping the video layer that contains the masked portion of the video and then duplicating the original video layer and layering the masked portion on top and the original unmasked portion below it. 

I tried the Alpha toggles (Option + 4, or 5, or 6), and all I get is a solid background of red, purple, or black (option + 4), to try and see the background and the mask contents at the same time, but no luck there.

But, is there another way besides the Pre-Comp trick I'm using?   Any thoughts out there as to what I'm doing incorrectly?

[Dave_LaRonde]

Your description makes me think you are looking at the layer window and not the comp window.  Check it out!

[Rick Gerard]

If you are on a Windows machine select the layers you are having problems with, press the U key twice and reveal all of the modified properties. Now at the bottom left corner of the timeline there are three icons. The second one will reveal both the switches and modes columns. Make sure you can see both. Now in the Project panel select the composition so you can see the composition properties in the preview just to the right of the thumbnail. As a last step make sure that you are viewing the Composition Panel, that it is set to Active Camera, that the resolution is set to Auto, that the rendering option is set to Final Quality and that the Magnification Factor is set to 50% for a standard HD Comp.

You should now be able to see everything that is effecting your layer and view the composition settings. If you cannot figure out what is goin on press Print Screen, then return to this forum and reply to this thread. After you have given us workflow details press return and then Ctrl/Cmnd + v to Paste the screenshot to the forum. If you are on a Mac you'll use Shift + Ctrl/Cmnd + 3 to take a screenshot and then you'll drag it from the desktop to the reply field. That is the easiest way for us to see what you are trying to do and point you in the right direction.

BTW, it would be a real good idea for anyone new to AE to set up a good training routine. The After Effects product home page has a bunch of getting started tutorials. The Search Help field at the top right corner of AE will also connect you directly to the help files and community resources that can help you solve specific problems. For example you could type "mask" there and read up on how to create, edit, modify and use masks.

[Guest · Accepted solution]

So, sometimes you just get stuck.   That's what happened to me.

If you have one single layer, say a video, create a composition with it.   Then duplicate it the layer in the timeline.  Disable the video for layer two.  Back at layer one, apply a mask, then apply an effect to that layer, something really obvious so you can see the effect and what's doing to the layer very clearly.  Now re-enable the video on layer 2.  Then you should (actually you will) see the effect on top of the original video, and that will look, in the comp viewer as a video with an effect applied to it.

I think that's the way it's typically done.  Thanks to the both of you.

[Dave_LaRonde]

-- OR --

     Just turn the effect on & off for a "with" & "without" view.  It's a lot faster & easier than going to the trouble of duplicating a layer & masking.