Isolating a Logo Using Layer Masks
Not all site designs are easy; some, you have to work for. And by some, I mean all of them.
Recently, I had to work out a problem with a site showcasing logos on a black background. The problem was the logo files I had were JPEGs of each on a white background. Laying out these white rectangle logos on the black background just wasn't working for me—not a good look. So I came up with a Photoshop method to cut the logos away from their white backgrounds, thus making them usable on any color background. I assure you this method works better and more often than other traditional isolation techniques, magic wand included.
Here's how I do it
1) Open the logo file in Photoshop and create a Duplicate Layer.
2) Desaturate the duplicate layer.
3) 'Select all' of the duplicate layer and Copy it to your clipboard. Make sure to then Deselect, this is important.
4) Next, add a Layer Mask to the duplicate layer. Choose 'Reveal All.'
5) Option-click (PC: Alt-click) on the Layer Mask Thumbnail. This will allow you paste right into the layer mask itself. Paste from your clipboard. Deselect.
6) Command-click (PC: Ctrl-click) on the Layer Mask Thumbnail, which will select all white pixels. Invert your selection so that you've got just the logo pixels selected.
7) Next, drop down to your original layer by clicking on the layer's thumbnail, making it your active layer.
8) Make a new Layer via Copy and you've isolated the logo.
9) This method may produce some logos with unwanted transparency, in which case you should duplicate the isolated logo 2 or 3 times, until it appears opaque. Then, merge these duplicate layers into one, solid, isolated logo.
In the End
That should do the trick. Using layer masks is an effective and efficient method to isolate logos from white backgrounds for use on any other background color. Here are some examples of logos created using this method, the the Boerne Wild West Day site.