View Full Version : What is the unit of the range or exposure?

May 31, 2011, 14:15:26
I use IC 3.1 and DFK 31AG03.
The function getRangeMin(VCDID_Exposure) and getRangeMax(VCDID_Exposure) return 1 and 300000. But I don't know what the numbers means. What are their units? “ms” or others?
Thank you very much.

Stefan Geissler
May 31, 2011, 16:07:17
The unit is 1/10000 second. 1 = 1/10000 second, 300000/10000 = 30 seconds.

September 19, 2011, 07:06:56
In photography, exposure range may refer to any of several types of dynamic range:
The Light sensitivity range of photographic film, paper, or digital camera sensors.
The luminosity range of a scene being photographed.
The opacity range of developed film images
The reflectance range of images on photographic papers.
The exposure range of a device is usually expressed in stops, which are equivalent to log2(c) where c is the medium or device's contrast ratio. For example, average Digital Video (DV) has a contrast ratio of 45:1, so its exposure range is roughly 5.5 stops. Film has an exposure range of approximately 14 stops, currently the highest in motion picture mediums.
Exposure is usually controlled by changing the lens aperture (the amount of light it gathers), the shutter speed (how long light is gathered) or sensitivity (how strongly the film or sensor ) responds to light. Changing exposure does not change the exposure range.