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Microscope Contrast issues

  1. Aug 12, 2015 #1
    https://www.dropbox.com/sc/eo2c8j4kd12pdvn/AACGJ8YZvk35BSX1BsBoKIIsa

    Please view the above image. I am getting awesome contrast on the periphery of the image but hardly any in the center. The sample is an H and E stained tissue and I just got the microscope in today.
    I am a rookie with microscopes so any ideas as to how to get this nice contrast across the image? Adjusting the brightness doesn't change much.
     
  2. jcsd
  3. Aug 12, 2015 #2

    Drakkith

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    What microscope are you using?
     
  4. Aug 12, 2015 #3
    It is an olympus BX60M. Got it for free from the university surplus department.
    When I adjust the field stop/aperture stop just right I can see the good contrast around the center but otherwise the entire field of view is at comparable resolution but very poor contrast.
     
  5. Aug 12, 2015 #4

    Drakkith

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    I'm sorry, I'm not actually too familiar with microscopes. Are you saying that if you adjust the stops just right it fixes the problem and you no longer have a contrast issue?
     
  6. Aug 12, 2015 #5
    No worries, just glad to have someone to bounce ideas with.
    No, the problem is with nearly every setting. Only when the stops are just right can I get a glimpse of the good contrast.
    I want to say that it is a vignetting type of refraction artifact but if so it's pretty sad to say that an artifact region provides the best image...
     
  7. Aug 12, 2015 #6

    Drakkith

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    Is the center bright spot just a contrast issue, or is the camera being saturated? You said adjusting the brightness doesn't help, but is that the brightness of the illuminating lamp, or just the brightness setting of the camera?
     
  8. Aug 12, 2015 #7
    The photo was taken via smartphone so it did pretty much get saturated in the center. The effect is less dramatic in the microscope when looking with the naked eye but still drastic (contrast difference between stained tissue and nothing). With a dimmer setting on the scope the color contrast is still dramatically different. I want the colors to 'pop' like they do on the periphery of the posted photograph.
     
  9. Aug 12, 2015 #8

    Drakkith

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    Okay, so the contrast issue is a problem both visually and photographically. Honestly I'm not sure what to do. If I find something that may help you I'll let you know. Hopefully someone else here on PF has more experience in this area and can help you.
     
  10. Aug 12, 2015 #9

    Drakkith

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  11. Aug 13, 2015 #10
    Does it happen with other objectives and/or eyepieces? (i.e. did you get any other objectives or eyepieces?)
     
  12. Aug 17, 2015 #11

    Andy Resnick

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    Assuming you have aligned everything correctly (http://www.well.ox.ac.uk/_asset/file/zeiss-guide-to-microscopy-from-the-very-begiining.pdf is a fantastic place to start), that looks like field curvature- the center may be in focus, but as you move towards the edge of the field of view, the image becomes defocused. What objective lens did you use?
     
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