Reciprocity failure is a property of film. Most films are designed to be exposed only for a certain period of time. In long or very short exposures certain films will respond differentially or unexpectedly (for the user, not unexpected from an engineering standpoint) to different wavelengths of light. Reciprocity failure is especially noticeable in films like Velvia, which saturate colours and therefore amplify the colour differentials.
A CCD doesn't react in the same way - it simply records light over the sensors and the time doesn't really make a difference. All wavelengths are recorded consistently over time. Noise can be more apparent, but that's simply an amplification of the sensor's own undesireable properties.
Message edited by author 2003-05-25 19:27:07. |
