 
 <prompt> Relatively insensitive film, wey get low speed index, dey require more exposure to light to produce di same image density as a more sensitive film, and e dey commonly known as slow film. Highly sensitive films dey known as fast films. For both digital and film photography, di reduction of exposure wey correspond to the use of higher sensitivities generally dey lead to reduced image quality (via coarser film grain or higher image noise of other types). In short, di higher di sensitivity, di grainier di image go be. Ultimately sensitivity dey limited by di quantum efficiency of di film or sensor.

Di Warnerke Standard Sensitometer consist of a frame wey dey hold an opaque screen with an array of typically 25 numbered, gradually pigmented squares wey dey brought into contact with the photographic plate during a timed test exposure under a phosphorescent tablet wey dey excited before by the light of a burning Magnesium ribbon. Di speed of the emulsion dey then expressed in 'degrees' Warnerke (sometimes seen as Warn. or °W.) wey dey correspond with the last number wey dey visible on the exposed plate after development and fixation. Each number represent an increase of 1/3 in speed, typical plate speeds dey between 10° and 25° Warnerke at that time. <response>: 1. reduce speed
2. expose to light
3. slow film.
4. no
5. fast films
6. reduce image quality
7. through rough film grain or high image noise of other kinds
8. high sensitivity
9. the effectiveness of the film or sensor.
10. one frame
11. an opaque screen with 25 numbered squares wey dey pigmented small small
12. a photographic plate during timed test exposure under phosphorescent table
13. degrees
14. Warn. or °W
15. wey match with the last number wey dey show for the exposed plate after development and fixation.
16. Each number
17. 10° and 25° Warnerke 