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Aeph
August 15th, 2008, 02:30 PM
I am trying to take a white background and make it transparent. How can I do this?

adewale
August 15th, 2008, 03:00 PM
Look at your layers panel for something like opacity and move the slider backwards from 100 till you get desired transparency.

Aeph
August 15th, 2008, 03:01 PM
I think that just changes the transparency for the entire layer.

smartboyathome
August 15th, 2008, 03:59 PM
Layer > Transparency > Add Alpha Chanel; or if you want to make a certain color transparent: Layer > Transparency > Color to Alpha.

Aeph
August 15th, 2008, 06:09 PM
I might be doing something wrong, but color to alpha just makes everything alpha and adding an alpha channel doesn't do anything.

smartboyathome
August 15th, 2008, 06:45 PM
What are the colors in your picture? Color to alpha should only make certain shades of the color transparent (ie, if you have a white background and light pastel colors, then the light pastel images will become partially transparent. Click on the color patch to change it to the one you want.

Adding the alpha channel just gives the layer the ability to use alpha, it doesn't do anything right away. With it on, you can erase to transparency, etc. You can use this to use the magic wand tool to delete certain patches of color. Just press the delete key after selecting what you want to delete.

AJB2K3
August 15th, 2008, 07:21 PM
Make to select>none before colour to transparency. That could be the problem

Aeph
August 17th, 2008, 04:19 PM
Adding the alpha channel just gives the layer the ability to use alpha, it doesn't do anything right away. With it on, you can erase to transparency, etc. You can use this to use the magic wand tool to delete certain patches of color. Just press the delete key after selecting what you want to delete.

That helped. One last thing: there is still a white-ish border around the image from the border pixels that make the image look more smooth. Is there a way to make these also transparent while giving it the same effect or do I just have to go through and delete them all?

smartboyathome
August 17th, 2008, 05:30 PM
If you undo the deletion and then raise the threshold of the magic wand (try 30), then it should get the white pixels for you.

Aeph
August 17th, 2008, 05:39 PM
If you undo the deletion and then raise the threshold of the magic wand (try 30), then it should get the white pixels for you.

Unfortunately, they're not all white. They are shades that blend the image with the white background for an anti-aliasing effect.

smartboyathome
August 18th, 2008, 12:21 AM
It doesn't matter. The fuzzy select tool will get rid of all colors that blend in to the threshold of the collor you pick.

dodle
August 18th, 2008, 12:38 AM
Ctr+A, then Delete

Unless I am misunderstanding the conversation.

smartboyathome
August 18th, 2008, 02:10 AM
Ctr+A, then Delete

Unless I am misunderstanding the conversation.

He doesn't want to delete everything, just the white space which is the background of the image.

Fhernd
August 9th, 2010, 01:56 PM
Thanks for your answer smartboyathome. Now, the page logo has transparency and shown fine. So long.

the_crayon_king
January 15th, 2012, 09:19 PM
I do a lot of sprite editing and I just use white as my background then : Layer> Transparency> Add Alpha Channel. Then I click the bucket fill/paint tool and for fill type I select BG color fill. Afterwards I just bucket fill the white parts which erases to transparent. I think you have to save as a PNG or GIF to save the transparency.

ofnuts
January 16th, 2012, 10:57 PM
I do a lot of sprite editing and I just use white as my background then : Layer> Transparency> Add Alpha Channel. Then I click the bucket fill/paint tool and for fill type I select BG color fill. Afterwards I just bucket fill the white parts which erases to transparent. I think you have to save as a PNG or GIF to save the transparency.And you get really good results that way?

shantiq
January 22nd, 2012, 05:58 PM
I am trying to take a white background and make it transparent. How can I do this?



if i understand your question simply

colours/color to alpha/pick white


that is the quickest way i know