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Cookie Cut Question


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While awaiting a render I thought I'd try an idea for the car chase sequence. I've taken some low res targa photos of the lego houses and mapped them onto four patch planes to composite within the multi plane chor option.

The question is, how do I get it to cut out the space were the windows are ?

 

Heres an example of one of the files.

 

Green_01.tga

I cut out the spaces were the windows were and left it transparent in TGA format. When rendered it shows the gap as a flat white ? Is there a way around that ?

regards

simon

 

Apologies here is a jpg version of the same fileGreen_01_1.jpg

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  • Hash Fellow

If the file has an alpha channel Cookie Cut will use the alpha channel to make the transparency.

 

If it doesn't have an alpha channel there is an option in the properties somewhere to choose a specific RGB "background color" that will be interpreted as transparent.

 

While alpha channel transparency allows some anti-aliasing of edges, background color is an all-or-nothing thing.

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  • Admin

If you are using After Effects to composite you have to tell that program to recognize the Alpha Transparency.

If using A:M the transparent areas will automatically be transparent.

In that way there is no need to use Cookie Cutter.

 

Edit: When opening your TGA image in an image editor I don't see any transparency.*

I'll add it and upload it.

Update: Updated image attached.

 

 

*Note: When creating a transparency in image editing progams make sure your background layer is empty/transparent. If it is just a layer of white then it isn't transparent.

Green_01_wAlpha.tga

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If you are using After Effects to composite you have to tell that program to recognize the Alpha Transparency.

If using A:M the transparent areas will automatically be transparent.

In that way there is no need to use Cookie Cutter.

 

Edit: When opening your TGA image in an image editor I don't see any transparency.*

I'll add it and upload it.

Update: Updated image attached.

 

 

*Note: When creating a transparency in image editing progams make sure your background layer is empty/transparent. If it is just a layer of white then it isn't transparent.

 

Robert and Rodney.

Thank you for your help.

I had thought that it did have a transparency but evidently goofed on that. Apologies.

Back to PShop.

Frustrating afternoon so far.

regards

simon

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  • Hash Fellow

I'll note that transparency on a "layer" in Photoshop will not equate to transparency in an alpha channel in a TGA.

 

 

However transparency in a Photoshop layer will equate to a transparency in a PNG that A:M can interpret correctly.

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  • Hash Fellow
I went back and redid the photos as jpg's using pure green for the background. Reapplied them as cookie cutters with the green set as the key colour. The desired cut didn't appear as hoped. Have I missed something ?

 

-you have the exact same color chosen

 

and

 

-"Cookie Cutter" chosen as "Type"

 

 

?

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-you have the exact same color chosen

 

and

 

-"Cookie Cutter" chosen as "Type"

?

 

Robert

Thank you for your reply.

I think so. I picked green 255 so there was no chance of missing it and cookie cutter was chosen as type.

Perhaps I should add,

V17g under OSX 10.68

 

regards

simon

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Here's my result with 0,255,1.

 

Note that there will still be problems with jpg compression around the edges. PNG or targa will get a cleaner result.

 

greenColor.JPG

 

 

Robert

Thank you very much once again for your help. The 1 in the blue channel was the problem. Back into Pshop I go.

 

Regards

simon

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Here's my result with 0,255,1.

 

Note that there will still be problems with jpg compression around the edges. PNG or targa will get a cleaner result.

 

greenColor.JPG

 

 

Robert

Thank you very much once again for your help. The 1 in the blue channel was the problem. Back into Pshop I go.

 

Regards

simon

 

Ps

Just gone back into Pshop and, according to the values set in the colour picker, its 0, 255,0 .

Most annoying.

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  • Hash Fellow
Just gone back into Pshop and, according to the values set in the colour picker, its 0, 255,0 .

Most annoying.

 

 

Possibly we have some difference in our "color manegement". My Photoshop is ostensibly set to not monkey with color when loading images ("Color management OFF") but various version of PS seem to address this control a bit differently.

 

However, I think an alpha channel will serve you better than color keying in this venture.

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Yeah, don't mess with the key color thing, just create a .png in Photoshop with actual transparency. I used to find the key color selector sort of hit or miss. that was a couple of versions ago and I haven't tried it in some time. Maybe it's improved, I hope so!

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Robert

Thank you for your help.

It was supposed to be a quick test while a render went through. I've got a test of the process but it is so rough I would blush to post it. I will try a proper version over the weekend.

I'm using CS2, which a mate described as "being in the stone age ", it may be but its more advanced than I.

regards

simon

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When saving to tga with an alpha channel in Pshop or AE remember to set the color depth to 32bits. Sometimes, you can ask for an alpha channel to be saved, but if you don't give it the extra 8bits of color depth the app will nix the alpha channel on you...

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When saving to tga with an alpha channel in Pshop or AE remember to set the color depth to 32bits. Sometimes, you can ask for an alpha channel to be saved, but if you don't give it the extra 8bits of color depth the app will nix the alpha channel on you...

Mat

Thank you for your help. I've been having trouble with just that. I kept trying to save as a TGA file and when reopened it no longer had an Alpha channel.

I was beging to wonder what I was doing wrong. One for the new day I think. The eyes are going a bit wonky after staring at the screen all day.

regards

simon

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  • Hash Fellow

Here is a thread that covered some of the details of creating proper alpha channels.

 

http://www.hash.com/forums/index.php?showt...++flaming++pear

 

and another with explicit steps...

 

http://www.hash.com/forums/index.php?showt...++flaming++pear

 

Note the mention of the Flaming Pear solidify plugins.

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