Good color negatives are known to record a dynamic range of 14-15 stops (a.k.a high exposure latitude) but fortunately they compress all this information in a narrow density range. This is actually the case for ordinary color negatives. So if your scanner has limited Dmax, it may still be able to represent the information contained in your film pretty well if your film's density range is limited. Note that while scanning, your scanner doesn't deal with the original contrast ratio of the photographed scene, but rather with the density range of the transparency it is scanning. As you can imagine, the higher the density range of the film you are scanning, the higher is the Dmax you need to represent that density range in digital space. Color reversal films, on the other hand, produce a very high density range while they are not as good in compressing contrast.Ī scanner's Dmax is the ratio of the strongest light signal to the weakest light signal it can record, and it varies with the sensor's bit depth. The good news is that negatives compress the contrast of the photographed scene very effectively in a pretty narrow density range.

Different emulsions can develop different densities in response to a light exposure of the same intensity.

Please note that film's density is only a translation of the original contrast of the photographed scene. The density of the film at each point refers to the fraction of the light that gets through the film if you illuminate it with some light source. In order to tell you why I have to clarify a couple of concepts.Īs you expose and develop a film, different parts of the film surface become transparent to different degrees as a function of the light exposure and the developer they have received. A scanner's Dmax becomes a limiting factor only when scanning high-density transparency material like color-reversal films. You don't really need to worry about dynamic range if you are planning to scan ordinary color negatives.

Vuescan multi exposure