(User’s Manual: D300S page 184; D300 page 186)
Multiple exposure is the process whereby you take more than one exposure on a single frame, or picture. Most of us will only do double exposures, which is two exposures on one frame.
Multiple exposure requires you to figure the exposure values carefully for each exposure segment so that in the final picture, all the combined exposures equal one normal exposure. In other words, if you are going to do a non-masked double exposure, your background will need two exposures at half the normal exposure value to equal one normal exposure.
The D300(S) allows us to figure our own exposure settings and do them manually, and it gives us Auto gain to help us with exposure calculations.
There are ...