One of the most versatile backgrounds in portrait and commercial photography is the white background. Giving the appearance of a white room with no walls is simple to create once you have the knowledge to do so. The digital age has made it simpler and cheaper to use. When I started in photography, it required a lighting setup that was cost prohibitive. at least two flash units on the background and two on the subject were requires. Now all it requires is four lights that can be bought at any hardware store, as long as they carry enough wattage to produce the needed f stop. Then you adjust the white balance in the camera to match the light source. As long as the light sources are all the same type, all is well.
First the background... I use a roll of photographic background paper but a piece of poster board will work as well. Flat white is best, it will keep lens flare down. The background is curved at the wall and floor and gives that seamless appearance. But how do we create that?
The background has to be overexposed by one stop to create pure white. In the image above, the background metered at f32 while the main and fill on the mitt and ball metered at f22. exposure was at f22. to make sure the curve at the floor of the background disappears the f32 reading is taken at the curve. The trick to this all is taking a reading at the back of the subject with the meter pointed at the wall. the reading has to be equal to the reading on the front of the subject or less (in this case f22). Any more light on the back of the subject will cause a halo around the subject keeping the edges from being crisp. If you have met these requirements you can photograph any subject on a white background.
White subjects in full length:
black subjects, though they are a little different and may take a couple of tries to get the exposure right and keep detail in the blacks.
This is a simple explanation of the technique to create this background properly. further research will give you more of an understanding of the technique. Hopefully I have stirred an interest in what I call rainy day photography. In this type of photography the weather doesn't matter.