If you’ve been reading my tips for a while, you may remember one I wrote about Convert to Grayscale. If not, let me refresh your memory. To convert color art to black and white, select all objects and go to Filter > Color > Convert to Grayscale. What I didn’t mention is the error message that you get if you’ve used Gradients or Patterns in the art. This Filter will not convert objects that have these Fills. So how can you get around this?
Select the objects with Gradient and Pattern Fills and Expand them (Object > Expand) to convert them to regular vector objects. Then, with these Expanded objects selected, use Convert to Grayscale and they should convert without a problem. A word of caution: Expanded Gradients and Patterns can contain hundreds of vector objects as well as Masks that hide much of what’s been Expanded. This can make additional work on your art quite difficult. Before Deselecting these Expanded objects, Lock them in the Layers palette.
Tip provided by Jeff Witchel, Certified Adobe® Training Provider.