David over at The News in Print has compiled a list of 21 free and paid alternatives to Adobe Photoshop. It is a good list, although it is still missing some of the alternatives like Picassa, openCanvas, ArtWeaver, ArtRage, Alias Sketchbook, Corel Painter, Expression Studio, Xara Extreme and the perennial favorite, Photoshop Express.

Which begs the question: with so many alternatives to Photoshop available, why would anyone pay the $500+ and continual upgrade fees to use Photoshop? Here are the bottom-line reasons:

• It is the industry standard. I can send a graphics designer a layered PSD file and 99% of the time no additional instructions are required
• Support includes thousands of books, videos, tutorials, brushes and scripts.
• You can ask any pro graphics designer or photographer how to accomplish a task and they will be able to show you on either of your computers
• One common file format for both PC and Mac

But perhaps the most important reason is that if you’re a professional photographer, you should be using professional tools. In the same way that you wouldn’t use a no-name consumer camera to photograph a wedding, you shouldn’t use an image editing program that hasn’t been tested by thousands of pros like yourself.

Having a high-powered PC or Mac that boots up the latest version of Photoshop (that you know how to use) shows your clients, your staff, your peers (and even yourself) that you are a professional deserving of professional prices for their services.