Digital Photography
- Electronic photodetectors capture img focus by lens
- Can be created non-photographically
· Computer tomography, scanners, radio telescope
- Img sensors read light intensity
· charge-coupled devices
· CMOS/ACTIVE PIXEL SENSORS
- Digital memory devices store digital img info as RGB color space/raw data
- Take pics, also store sound and video; video tapes have same functionality as dig cams
- Factors of quality
· Pixel count: manuf advertise b/c consumers can easily compare
· Processing system: turn raw data -> color-balanced and pleasing; 4+ megapixels perform better than higher-end
- Lens quality: resolution, distortion, dispersion
- Capture medium: CMOS, CCD, negative film, reversal film, etc
- Capture format: pixel ct, dig file type
- Processing: digital and/or chem processing of negative and print
- Pixel Count
· Difficult to compare resolutions based on megapixel ratings
· Incr detail in resolution- compare by looking # of pixels across(down) pic instead of total # of pixels in area
- Dynamic range- range of luminosity that can be reproduced accurately; highlights/shadows
· DCams can show blown highlights in img review, so photographer can re-shoot w/ modif exposure
- Storage using memory card or flash memory
· SD format
· XQD card format latest form
· Modern DCam internal memory for ltd capacity for pics transferred to or from card
- Convenience
· Amateurs able to send imgs by email, place online, display digital pic frames
· Flexibility, lower long-term costs outweigh initial price disadvtgs; capital cost vs film photography- require continuous expend of funds
· Editing capabilities on comps; color-balance, mainp imgs
- (Digital vs Film) Advantages
· Elim need to purchase photog film, save $
· Every DCam has video mode, HD capability
- (DigitalvsFilm) Disadvantages
· Sensor size smaller on consumer-lvl than expensive/professional cams
· Long delay b/w shutter release button pushed and actually taken
· Video mode poor focus in low-light situations
· Img capability doesn’t function as subject is filmed
- Img noise/grain: dcam noise similar to film grain; @ high ISO lvls, grain/noise is more apparent in final img
- Speed of use: start up times under ¼ seconds
- Color reproduction: diff films&sensors have diff color sensitivity; color space
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