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# alpha channel question

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 alpha channel question on Jul 15, 2013 at 1:19:12 pm

I'm trying to compose a red solid, a photo and a clipart (which I created an alpha channel in photoshop) so as to show the red solid, the tv clipart in the middle of the screen and through the inner rectangle of the clipart, the photo below.

I placed the clipart on the top layer, the red solid in the middle layer and the photo below.

http://i300.photobucket.com/albums/nn13/sifidis/Comp10-00-00-00_2_zps49aede...

I selected the red solid and assigned the alpha matte to it. the result is below. what am I doing wrong?

 Re: alpha channel questionon Jul 15, 2013 at 2:29:07 pm

If I understand correctly, you want the red to be the background, and the picture to be in the tv? Put the red solid on the bottom and just use a rectangle mask around the picture that is needs to go in the tv.

Johnny Cuevas, Editor
Thinkck.com

"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.

 Re: alpha channel questionon Jul 15, 2013 at 2:34:19 pm

Nothing's blocking the photo.

There's a number of ways to approach this: a mask on the photo is probably the fastest.

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"Putting the HARM in 'harmonica' since 2005."
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 Re: alpha channel questionon Jul 15, 2013 at 2:51:52 pm

I know I can do that with a mask, but I'd rather create that mask from the alpha and not with the pen tool. The reason is that the rectangle in the tv is not perfect rectangle (the corners are kind of round) and I want to learn the technique for more complex geometry, and I know it can be done (for the alpha converting to mask)

 Re: alpha channel questionon Jul 15, 2013 at 3:14:11 pm

To do what you want you need to make a "TV" with the screen filled in also(or just the screen). Then you could use that as an inverted matte for the red solid, or a alpha matte for the video you want to be in the tv.

Johnny Cuevas, Editor
Thinkck.com

"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.

 Re: alpha channel questionon Jul 15, 2013 at 5:47:24 pm

In that case, I suggest you examine the Silhouette modes and pre-comping.

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"Putting the HARM in 'harmonica' since 2005."
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