Digital Photomicrography Tips and Tricks.

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A Picture says thousand words!
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Digital PhotomicrographyTips and Tricks.Fiji
Society for Microbiology18 Sep - 2004

• Dr. Venkatesh M. Shashidhar.
• Associate Professor of Pathology
• Fiji School of Medicine

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Introduction

• Camera Obscura Dark chamber.
• Like human eye ?digital
• Optical / Conventional - Storing light
  information on film / print. (dots)
• Digital - storing image as codes/digits
  (computer).
• Several formats for image files.

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Digital Image basics

• Common digital image formats.
• Image.BMP, JPG, GIF, TIF
• Two major types Bitmap and Vector.
• Bitmap dots of image information. Good for
  photographs or high resolution.
• Vector information of blocks. Good for drawings
  small size, magnification

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Bitmap / Pixels / Resolutione.g. BMP, JPEG, TIFF
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Vector Image - Gif
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Image file formats

• Different file formats - quality and size.
• Vectors (drawings) Bitmaps (photo)
• BMP windows large/okay. 1-10MB.
• JPEG - Joint Photographic Expert Group
• small okay quality popular compressed file
  size lt500KB.
• Tiff Large, good, artists - gt100 MB.
• Gif Vector Animation.

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Image / pixel / Screen / File - size

• Computer Screen fits image to its size
  irrespective of its original size.
• Check magnification / resolution / size.
• Standard computer screen 640/480, 800/600
  1024/768 pixels.
• Resolution pixel dots/image
• Color depth 2 / 8 / 16 / 256 / 16 bit / 24 bit
  / 32bit (millions)
• Brightness, Contrast, Focus/sharp
• With standard JPEG, 16bit color depth, screen
  size image is around 50-500 kb.

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CCD/Video Camera basics

• CCD-Charged couple device
• Collection of tiny light sensitive diodes
• produce Analog electrical signals to light
  TV/Projector.
• Analog to Digital Converter (ADC) cards convert
  Analog signal to digital information seen and
  stored in a computer.
• Digital camera direct codes from CCD.

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Digital Photomicrography
Millions of colors 256 colors 16
colors 1515 k 876 k 98 k File size
Width x Height x color depth
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File formats size quality
PSP PSD BMP JPG 2552 2493 990 61 kb
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Camera Summary

• Eye ? Retina ? cones ? nerves ?Brain.
• Optical ? neg film ? Pos Image.
• TV/Analogue ?CCD ?signals ? TV/Projector.
• Digital ? CCD ?ADC ? digits/codes ?
  Computer/memory card.
• Lens Focal length, Resolution, format.
• JPG 50-500kb (GIF TIFF)
• Standard Screen size 800/600 pixels.

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What you need

• Image capture camera, photo microscope,
  scanner.
• ADC cards only if camera is not digital.
• Image editing software photoshop, paintshop /
  proprietary softwares.
• Office software presentation.

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Photomicrography at FSM

• Olympus BX 40
• JVC digital CCD camera. 625 line
• RCA S-Video out.
• Analogue
• ADC card (AV/TV grabber card)
• Pentium computer.
• Use Paint Shop Pro for image editing.
• Cost 29,000 A

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Projection Microscopy _at_ FSM
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Economical option

• Motic digital microscope.
• Built in CCD camera
• Digital converter card
• Analogue out AV S.Video
• Digital ? USB ? computer.
• Comes with image editing software.
• Direct connection to display / computer.
• Cost lt 5,000 F

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Uses of Photomicrogrphy

• Store / Archival
• Discussion Patient / professional.
• Consultation Local/remote, comparisons.
• Telemedicine / telemicrobiology.
• Presentations, conferences, publications.
• Education student, CME.
• Quality assurance RCPA.

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Questions?