I have just got my proper light box and studio lamps recently and I am studying on what background is suitable for what objects.

One thing I found out was that the exposure need to be increased on white background for 1 - 2 steps, and vice versa for black background using average / auto metering.

This is because when using white background, the sensor on the camera might thought it is bright, but the object is actually darker then the white background, and if the exposure is not adjusted, the object will become under exposed (too dark).  Same as black background on the other way.

It is the same concept when taking photo at night, and also taking photo on beach / in snow scene.  Some experienced photographers might know that they need to adjust the exposure.

Usually camera come with exposure adjustment range from -2 to +2 step with increment of 0.5 steps.  A more advanced camera will have -3 to +3 steps with increment of 0.3.

My camera is having -2 to +2 setting with increment 0.3.  But I discovered that when I use exposure bracketing, it automatically can go up to -3 to +3 (without showing on camera display).

Which one do you prefer, white or black background?