Transparency query

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Esky
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Transparency query

Post by Esky »

I've had a good google around, but can't seem to find an answer to my problem ... which is ....

If I take an image - say coloured letters on a white background, and then use the 'Colour to Alpha' set at white, the result is I get the letters on a transparent background, but they can be of different degrees of transparency (I guess due to the amount of white they initially had in them).

If I do Layer, Transparency, Alpha to Selection - this gives me the outline of the letters that I now want to fill in with fresh colour.

But if I do New Layer, and then choose bucket fill, the resulting fill is at the same transparency level as the letters that I have selected from. I can click bucket fill 2-3 more times to get a solid fill, but then I lose the anti-aliasing effect of the edges of the fill area - this means I end up with jagged edges.

My questions is: After I have done 'Alpha to Selection' (and before I do bucket fill) is there any way to 'reset' the transparency level of the selection to 100% so I get a cleaner fill?

Or Is there another method I can use to achieve my goal?

I hope my query makes sense - any help will be greatly appreciated !!

Thanks in advance,

Esky.
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akovia
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Re: Transparency query

Post by akovia »

Hi Esky,
I went through this same quandary ages ago. What I've found is there are ways to work around this, but it will never be perfection like using the path tool to render out what you want.

The problem you are having is when you use color to alpha, it is turning whatever amount of white (in your example) is in the letters to alpha. So what is left is every other color with a partial alpha where the white used to be.

The best way I've found to work around this is to use the alpha channel in the curves tool to turn the partial to full alpha. This again will give you jagged edges, but I do a selection, invert it and grow and feather it to get rid of the edges. If you want to post an image you are working with, I can show you how I'd do it and you can decide if it's worth the trouble for the results.

Also, the quality of the image will make a big difference.
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Esky
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Re: Transparency query

Post by Esky »

Hi Akovia,

thanks for your reply. I don't have a particular image at the moment that I'm working with .. it's just an issue that I've encountered now and again over the last few weeks now that I'm attempting to do more logos as well as banners & thumbs!

On one hand, I'm glad that this is a situation that others have also encountered and it's not just me ... but on the other hand, I'm sad there is no 'magic option' that I just missed.

As always, there's more than one way to skin a cat, so I will just have to hone my other techniques (few as they may be) and watch a few more youtube vids.

Thanks again,

Esky.
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ArieS
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Re: Transparency query

Post by ArieS »

Yeah I remember us talking about that with akovia and wondering if PS had a Color to Alpha option or something similar. The answer is no. I also gave that a shot with Gimp as well with different images and my results were that there was some floating pixels left all around.
So as akovia stated, The Pen/Path Tool is your best friend. It will take you a few weeks to really get used to it but once you do, you can pretty much do anything you want.
And btw, the Pen Tool in Gimp is much easier to handle than PS Pen Tool :)
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akovia
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Re: Transparency query

Post by akovia »

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Esky
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Re: Transparency query

Post by Esky »

Hi Akovia,

Thanks very much for taking the time to create the video for me - it's shown me a couple of useful features that I'm sure I'll be using when the situation calls for them!

Cheers,

Esky.
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