Expert: Scott Valentine - 10/3/2007

Question
I have recently purchased Photoshop CS3. I have several logos that when put into this program have a white background to them and I want to delete this white background so I can put an image behind the logo or change the colour of the background the logo sits on. Firstly I can't work out how to do this as the logo is all on one layer. Also once I have worked out how to delete this white background from the logo does that mean that if I then import the logo into Illustrator it will be free of the white background still so I can add a different colour background or image.

Answer
Hi Sarah,

There are a couple of ways to deal with the background. But before you get started, duplicate your background layer so you are not working on the original. This gives you a safe way to try different techniques. Also, be sure your logo is in RGB so you have access to the tools you'll need (Image > Mode > 8-bit RGB).

A simple first-pass approach is to try the Magic Wand tool, and enhance the selection using the new Refine Edge tool. Both of these tools are covered in the help files, and are worth reading about. The important thing to note about the Magic Wand tool is that it can select either *all* pixels in the color range, or it can select *contiguous* pixels (pixels that are touching eachother and are of the same color). Using the 2nd option, you can CTRL/CMD + Click in additional areas or colors to add to your selection.

Once you have your selection, I recommend creating a layer mask, rather than deleting the white areas. This allows you to make detailed adjustments and tweaks to the outline by working on the mask. It's also nondestructive, so you can try new things without fear of damaging the image.

Another tool you should consider is the Pen Tool. This creates a vector outline you can also store in a vector mask. This has the advantage of giving very clean edges, and great control over curves. It will also feel similar to Illustrator, though greatly reduced in features. Simply create a Bezier outline using a vector mask (again, help files will give you everything you need to know).

Depending on the detail and edges in your logos, there are additional techniques that may be more helpful, but they get more specific and would take too long to present here. They typically involved blending, channel operations, and some advanced trickery.

If you choose to use the vector mask method, you can import that vector mask into Illustrator straight from the PSD file. However, you can also save your image to a PNG-24 format and then import or place that into Illustrator. It will be important to turn off layers below the masked layer so you can see the effects and preserve transparency.

I don't recommend changing the background in Illustrator unless you plan to convert the entire thing to vector (which is a reasonable thing to do). If you just need to replace the background of a raster image, you might as well do it directly in Photoshop. Doing it this way opens up some advanced blending techniques that are not available in Illustrator. Especially helpful will be using Blend/If or layer blend modes to really make the combination flexible.

I hope this helps - if you have further questions, please feel free to ask!

-Scott