Flash has the major advantage of being completely under the control of the photographer. Exposure, and the direction and quality of the lighting, can all be set-up in almost any location regardless of ambient light considerations. Flash is also colour balanced for daylight so it is possible in most cases to mix the two sources. Where window light is incorporated in an image, it is important to balance the flash output with the natural light.to achieve a neutral result.
Off-camera flash is essential for flexibility and the best results. With modern equipment is is very easy to set up and use multiple flash units and control the resulting exposure. A master flash unit that triggers one or two remote slave units provides all the flexibility a still-life photographer should need. It is also necessary to have available suitable lighting stands so that each unit can be placed at the desired location and height.
The output from the flash units can be diffused using soft-boxes or by bouncing the output from a white wall, ceiling or reflector. Remember that bounced flash acquires the colour of the surface from which it is reflected. Reflectors also need supporting in the correct position, but this can normally be achieved by placing them on some item of furniture if no assistant is available.