In the manual for my new D90 there is a secontion called Multple Exposure, which apparently happens in the camera. What is the difference in Multiple Exposure and setting your camera for auto exposure bracketting and using Photomatrix to make an HDR? thanks joanlvh
Multiple exposure just adds new images to the first one without differentiating between bright and dark areas. You can still get bits that are too dark or too bright in the final image. The HDR combination effectively lets you extract the dark bits from one image and the light bits from another to get the best of both images in the final result.
Mulitiple exposure is not useless but HDR is not the purpose for which it works best. It can let you combine a series of shots of a scene that is changing colours (a floodlit fountain at night, for example, in which the lights change colour every few seconds) in which no one colour is available long enough for a single image to capture it correctly. A longer exposure would not show any individual colour.
Bracketing means taking 3 (or more) separate exposures of the same thing in order to make sure you get the best exposure. You can either pick the one best, or combine them in an HDR image.
Multiple exposure is taking more than one picture in the exact same frame (you get one file in the end). With film it means taking two (or more) pictures without advancing the film. This has nothing to do with HDR and is more about creative effects.
