There are many pieces of equipment that are optional for a wedding photographer and there are some equipment that is mandatory.
Let's start with the obvious..the camera. To really be able to be versatile and create superb photographs, a Digital SLR should be one of your first purchases. If you are new and your budget is small, I personally recommend the Canon XSI Rebel. It is a very good camera at a reasonable pricing point. You can normally purchase a Rebel with two kit lenses for under $800. And what makes it better, is that the kit lenses have built in image stabilization. This should be good enough to get your started. But keep your eye out for a back-up camera.
The flash is very important. I have owned Minolta, Nikon and Canon products. If your budget allows, you may want to consider the Canon 580EXii. This flash is a bit expensive. It is almost $400 in most stores, but well worth it. When I used smaller flash units with less power, the problem of not being able to bounce a significant amount of light off of high church and reception hall ceilings presented itself. Not having enough power could ruin most of the photographs for a particular event. Don't go cheap on your flash unit.
Although this is not a complete list, some consideration should be given to either editing software or a color balancing tool. Most new camera come with some very basic image processing software so you may be able to get away with not purchasing top dollar software immediately. Much of my editing time during the early years of my business was spent trying to color balance (setting white balance). I would recommend purchasing the Expodisc color balance tool. It costs about $100 and will last a lifetime. If the color balance is correct in-camera, it will save you valuable time while editing.
When I buy retail, I try to buy at Cameras Etc in Delaware. Delaware is a tax free state and that saves you a fair amount of money when you are purchasing electronics. There are few true camera stores left in the U.S. Cameras Etc is a real camera store with real camera experts staffing the business.
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