exposure and dynamic range low contrast | high contrast
Post on 19-Dec-2015
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![Page 1: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/1.jpg)
Exposure and Dynamic Range Low contrast | High Contrast
![Page 2: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/2.jpg)
Histogram: plots pixels according to brightness: L-R, Dark-Bright
Low contrast: Most pixels in middle, few very dark (shadows) or very bright (highlights) areas.
Result: Flat, boring picture. No defining characteristics.
![Page 3: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/3.jpg)
Histogram: plots pixels according to brightness: L-R, Dark-Bright
High contrast: More pixels toward edge, in very dark (shadows) or very bright (highlights) areas.
Result: Interesting, dynamic picture. Sharply defined characteristics.
![Page 4: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/4.jpg)
Histogram: plots pixels according to brightness: L-R, Dark-Bright
Low contrast: Most pixels in middle, few very dark (shadows) or very bright (highlights) areas.
Result: Flat, boring picture. No defining characteristics.However, low contrast can always be edited into a high contrast image
![Page 5: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/5.jpg)
Low contrast
High contrast
High contrast has caused this area to be completely white, destroying all detail. It is impossible to get this detail back – this is known as a “blown highlight”.
![Page 6: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/6.jpg)
Low contrast
High contrast
High contrast has caused this area to be completely black, destroying all detail. It is impossible to get this detail back – this is known as a “crushed shadow”.
![Page 7: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/7.jpg)
Shadows and Highlights
When the photowell is full, a highlight occurs. No photons after this are recorded, so all detail for these pixels are lost.
If the electron count is below a certain threshold, it is just recorded as black. So if there aren’t enough photons, all the detail in those pixels is lost.
DynamicRange
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Large dynamic range: very bright and very dark areas in same scene
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![Page 10: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/10.jpg)
![Page 11: Exposure and Dynamic Range Low contrast | High Contrast](https://reader038.vdocuments.us/reader038/viewer/2022103022/56649d2c5503460f94a02614/html5/thumbnails/11.jpg)
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The camera has a limited dynamic range. Thus it can only capture a certain portion of the total dynamic range of the scene.