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Add Transparency

Oct 4, 2012, 17:35
Post: #1
Add Transparency
   

The edges of this fabric are semi transparent. The grey colour to the area where the arrow points is caused by the photo's original background. Now I'm wondering is it possible to recreate the transparency so that the colours from a new background will show through. I've tried colour to alpha but that makes most of the image transparent.

The rest of the image is mostly black and greys with a splash of red. I would post the entire image but it's copyrighted - DA stock model - so I don't want to break the rules.

Thanks for any help.

[Image: DjIVv.png?1]

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Oct 4, 2012, 21:49 (This post was last modified: Oct 4, 2012 22:05 by ofnuts.)
Post: #2
RE: Add Transparency
If you do a selection first the C2A will only apply to the selected pixels. But you cn even avoid that:

1) remove white background: Wand select bacground, "Select/grow 1px", C2A on white.
2) Sample the cloth color, on a side image (or layer), paint with it, and invert the colors.
3) Apply C2A on your image, using the inverted color.
4) add temp pattern color under image to eyeball transparency
4) Ad layer mask to image, and transfer alpha channel
5) Start levels tool (which will apply to the mask).
6) Drag right handle toward the middle (makes fully opaque the parts that where mostly opaque)
7) Adjust transparency of thinner parts using the middle handle
8) Apply layer mask

[attachment=1503]

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Oct 5, 2012, 17:16
Post: #3
RE: Add Transparency
Thanks. I'm going to give this a go now.Cool

[Image: DjIVv.png?1]

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Oct 6, 2012, 10:27
Post: #4
RE: Add Transparency
   

Here's another bit of Gimp magic that works a charm. Just follow the instructions as given by Ofnuts and the thin edge of the fabric turns transparent, great stuff.

The only problem I had with this is when using the levels tool. It works fine when working on the dark colours but not so for the rest of the image, reds, whites, flesh tones, that kind of thing.
To get around this problem I used another selection of the model - on a separate layer - that hadn't had colour to alpha applied to it. I then used a soft eraser to brush out the edges of the new selection so that the transparent areas on the colour to alpha layer showed through.
This was quite slow to do but at the end of it I was left with the best selection that I've done to date. Cool

[Image: DjIVv.png?1]

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