Image Input Image acquisition or digitization. Sources include- Cameras Video camera w/ framegrabber Digital CCD camera w/ interface card Color or Monochrome Flatbed Scanners Photomultiplier Tubes Electron Microscopes
Dec 30, 2015
Image Input
Image acquisition or digitization. Sources include-
Cameras Video camera w/ framegrabber Digital CCD camera w/ interface card Color or Monochrome
Flatbed Scanners
Photomultiplier Tubes
Electron Microscopes
Image Quality
Image Quality is critical. A good image depends on a good specimen.
Optimize input conditions - Select suitable acquisition system and conditions to acquire the best possible image.
Good specimens and proper imaging conditions will make image analysis much easier.
Limitations of Our Eyes
5 Gray Levels 10 Gray Levels
20 Gray Levels 40 Gray Levels
Instrument Setup
• Microscope adjusted for Koehler illumination
• Match magnification to object size and camera resolution
• Calibration- White Balance Dark CurrentExposure Time
• Background Subtraction
Camera Adjustments
• Adjust camera for best dynamic range
• Gain and brightness
• Exposure time
• For intensity/density measurements turn off autoexposure
• For fluorescence turn off autoexposure
Saving Image Data
Images are normally saved as TIFF (.tif) files.
Do not save images as JPEG (.jpg) files!
OK for e-mailing/viewing only
Loses data integrity
Could be impossible to analyze
Does not save computer memory or processing time
TIFF v. JPEG
TIFF JPEG