The concept of portraiture goes back a long ways. It's even been said recently it's in our genes. Instinctively, when someone picks up a camera it's to photograph another person. The thing that has kept most people from making portraits is lack of training and equipment to produce the photographs worthy of being called portraits.
Ordinary photographers can overcome that now that they have alternatives to chemical darkrooms, they just have to put what's already in their camera bags and computer rooms to work.
We may have time enough to use “Hot Lights” during the portrait session so you can learn to position Key and Fill lights, in combination or with a reflector, to get a desired result, and subsequently be able to duplicate the setup inexpensively in your own “studio”. Basically, when using “Hot Lights” your camera can either be set Manually, according to the light meter reading, or on Aperture Priority, in which case you can select the desired f-stop and your Auto Exposure feature will set the shutter speed appropriately. This exercise will illustrate several basics of portraiture, the advantages of using large apertures, and the benefits to be obtained by doing so. Depending upon lighting and film speed , you may end up using very slow shutter speeds, so plan on using a tripod.
The ideal camera, under our circumstances, is one based upon the 35 mm Single Lens Reflex format, either film or digital. Following that is the Digital Rangefinder point and shoot (P&S) type that incorporates a LCD screen that allows you to preview your picture before and after you shoot it. With respect to the 35 mm format, 85 to 105 mm is an ideal focal length for portrait lenses. This focal length range allows you to avoid distorting the subjects nose, arms or legs, while maintaining a good working distance. It also allows you enough control over depth of field to emphasize the eyes, facial features and hair, while de-emphasizing the background. Apertures between f-5.6 and f-11 are generally used to achieve these affects. If your lens has a “hyperfocal” scale on it you can easily read out the in-focus range for any f-stop and see that the smaller the aperture (larger numbers), the longer the range, and the larger the aperture (smaller numbers) the shorter the range. Wide angle lenses have large in focus ranges while telephoto lenses have small in focus ranges. So you can see the logic in selecting a medium telephoto for portraiture.
Point and shoot (P&S) digital cameras, as well as some advanced DSLR's have Icons on the Mode Control Dial to aid in selecting the proper camera mode for various subjects; a person's head for portraits, a mountain for landscapes, a skier for action, and etc. Depending on the individual P&S camera the depth of field in the “portrait” mode may or may not limit depth of field adequately. Their physically small lenses and actual short focal lengths conspire to create long “in focus” ranges even at large apertures. You should familiarize yourself with your camera controls before the shoot to make sure that you know how to set it up for portraits, and determine if it's adequate for the purpose.
To use your camera with strobes you must have a built in PC cord receptacle, or a PC cord adapter that fits in your camera's hot shoe.(King Photo stocks them) Don't plan on using the integral flash unit on your camera, because your flash could override the strobe system's remotely triggered flash system. This has caused problems and delays in the past, so, a word to the wise.........etc.
When using “Strobes” in portraiture, even with Digital Single Lens Reflex cameras (DSLR's), it's customary to use Manual Mode settings for shutter speed and f-stop, as determined by an “Incident” light meter reading taken at the plane of the subjects face, facing the strobe. The shutter is commonly set at 1/125th and the f-stop varied between f-5.6 and f-11 to adjust the exposure. The strobe itself fires at a very high equivalent shutter speed and precise light value during the time the camera's shutter is completely open, thus overriding the cameras shutter timing function. A very slow shutter speed could result in a “ghost” image, from available light, whereas a high shutter speed could result in a partial, or no picture because of masking by the focal plane shutter. The person using the light meter will provide the settings for the photographers, and adjustments from those basic numbers can be made by individual photographers.. The procedure is to adjust the f-stop slightly: If the picture is dark add light to increase exposure, or if the picture is light subtract light to decrease exposure. Adjusting the camera's Exposure Compensation doesn't work in this situation.
The most flattering light for most portraits is soft and off-camera, and it's advisable to select a film with an ISO between 50 and 200 to avoid the excessive contrast that results when using higher speed films. And, more to the point, slower speed films simply produce better flesh tones in portraits than fast films. (Using higher ISO's in digital cameras does not have the same effect on contrast, however, and they are sometimes subject to “noise” that appears like grain in film at higher ISO's). Fujichrome “Astia”, Kodak 100SW (ISO 100 Slide films); Fuji NPS and Kodak Portra (ISO 160 color print films) are good choices for slide or print film.
Three Megapixel, and up, digital cameras can produce very good 8 by 10 enlargements provided you set them on the highest resolution settings. Look for, at least, JPEG High, Fine, Large, and de-select “Vivid” if that is an option. This might be the time for you to buy that large capacity, high speed Compact Flash Card you've been wanting. (Make sure your camera can use it)