Essential Equipment - Camera and Lenses
If you're contemplating setting up a home photo studio then the chances are that you already own a digital SLR camera, so you've already got the most vital ingredient. There aren't many compact cameras that are going to be much use for studio photography, but there are a few, such as most of the Canon G-series and Fujifilm's high-end superzoom cameras such as the S200EXR, both of which have a flash hot shoe.
Almost any DSLR will do the job, but obviously some are better than others. A feature to look for is an X-sync socket, which is used to connect the camera to a studio flash system. These are mostly found on expensive high-end cameras such as this Pentax K-7, but some mid-range models do have them. If yours doesn't don't worry, you can always buy an adapter that clips onto the camera's hot shoe. Another useful option is a flash sync or 'X' setting, again usually only found on more expensive models.
When it comes to lenses the choice is more a matter of personal taste, but as I mentioned earlier, it's usually a good idea to stay away from wide angle lenses unless you're aiming for a deliberately distorted effect. The most flattering focal length for portraits is around 80-100mm (On an APS-C camera around 50-70mm, on Four Thirds cameras 40-50mm), so you're better off using the wider end of a short telephoto zoom than the standard 18-55mm wide-zoom that comes as a kit with most current DSLRs. My personal favourite portrait lens is an old manual focus f.3.5 28-70mm Tokina lens, which on my Pentax K-7 is equivalent to approximately 42-105mm.
Many photographers prefer to use prime (non-zoom) lenses for studio photography, usually of around 80mm focal length. There are several reasons for this. Most prime lenses have wider maximum apertures than the equivalent zoom lenses, giving much more precise control over depth of field, and in many cases their optical quality is better too. Another reason is that if you're shooting a set of photographs of the same model, using the same focal length for every shot creates an sense of consistency from one shot to the next.
Obviously a tripod is also a useful studio accessory, but in fact when shooting a live model using studio flash it's often easier to hold the camera.