Tony M May 17, 2010:

Good point, Chris! I had assumed it was a transmission densitometer simply because they talk about 'film' — so one assumes it is a transparent medium, unlike photographic paper (or other opaque materials).

chris collister May 17, 2010:

Oddly written... I agree with Tony that some aspects of the text are odd. For example, the way it's written seems to suggest that the H&D (Hurter, by the way, not Hunter) curve is a ratio of log intensities, while it is, of course, the log of the ratio of intensities. Given that it's "filtré" and not "filtrée", the filtered refers to the 1/10th, in which case, technically, there is a verb missing, eg. if only 1/10 of the incident light IS (or has been) filtered, then D = 1, etc. "D" of course stands for density, and generally the denser the film the greater the value of D.
If we assume this is a transmittance densitometer, then Tony is quite correct, and it only makes sense if you translate "filtered" as "transmitted". Eg if only 1/1000 of the incident light has been transmitted, then D=3. However, the picture changes entirely if the densitomer is a reflectance type, so the "lumière émise" is actually light reflected, not transmitted.