Camera lowest intensity of illumination Lowermost intensity of illumination is lowermost intensity of illumination it is the brightness when the scenery that be photographed low the video signal n that makes camera is outputted to certain level is low the scenery brightness when providing a value to some is worth. The lowermost intensity of illumination of general color camera is 2 ～ 3LUX, of intensity of illumination determining is with be in coefficient of certain camera lens aperture is premise, accordingly, cannot see the lowermost intensity of illumination that indicates in camera manual only, the bulk that its intensity of illumination is worth should leave in same aperture coefficient by camera. Lowermost intensity of illumination is smaller, camera class is higher. Relative to at chromatic camera character, because black and white camera is only right without chroma processing of the light lose by force (brightness) signal is sensitive, so the intensity of illumination of black and white camera wants than chromatic camera intensity of illumination low, can accomplish 0.1LUX to be when F1.4 commonly, as to crepuscular camera lower. The knowledge of concerned aperture coefficient consults please camera lens.
Of video signal nominal the value is 1Vp-p, mark fiducial value is 0.7Vp-p, the video signal value when lowermost intensity of illumination arrives for 1/3 the standard establish of 1/2. So camera is in the image when lowermost intensity of illumination, will never " as daytime same " . Additional, the image definition that camera produces when lowermost intensity of illumination, undertake measuring type with card of TV signal test, its are black and white the stripe of alternate with, requirement black reflectivity is bordering on 0% , white reflectivity is more than 89.9% . And we do not have such requirement sometimes when the spot observes, for instance: The reflectivity of leaf and meadow is very low, contrast is very small, obtain clear picture not easily. Because this is used actually in the center cannot serve as the level that measures spot environment intensity of illumination with the lowermost intensity of illumination with nominal camera. Camera believes comparing of a confusion of voices Believing a confusion of voices to compare also is a of camera main function index. When camera absorbs brighter setting, the picture that monitor shows is compared normally lively, observer sees the interference a confusion of voices in the picture is nodded not easily; And when camera absorbs darker setting, the picture that monitor shows is dimmer, observer sees the interference a confusion of voices of shape of the snowflake in the picture is nodded very easily right now. Those who disturb aspect of a confusion of voices is strong weak (the influence rate that also violates a confusion of voices to choose pair of pictures namely) the stand or fall that compares index with camera letter a confusion of voices has immediate concern, namely the letter a confusion of voices of camera is taller than jumping over, the impact that disturbs a confusion of voices to choose pair of pictures is less.
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