Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Total magnification of microscope

  1. Dec 21, 2009 #1
    I have a small question. I am using coumpound microscope with video attaced and I got using 40X times objective and 10X eyepiece that my magnification on video screen is 1000 times.I know that between eyepeace and video system where is a beam splitter and between beam splitter and video screen there is one more lense which gives additional magnification.So my question is :if I got 1000 total video magnification it was from 40(objectives)x10(eyepiece)and 2,5(additional lense between beam splitter and video system)
    or it was from 40(objectives)x25(additional lense between beam splitter and video system)?
    I am not sure when I use video system that I have to add eyepiece multiplication or not.Please help me!
     
  2. jcsd
  3. Dec 21, 2009 #2

    mgb_phys

    User Avatar
    Science Advisor
    Homework Helper

    You can't really quote a magnification for an image forming system in this way.

    If the video system is fitted directly to the microscope then it doesn't go through the eyepiece, the maker should have specified a magnification of the relay optics which gives you the magnifiction from the sample to the video chip - it might quote this in pixel size.
    Once it's in the camera the magnification doesn't really mean anything - it would depend on the size of the monitor and how far away you are standing.
    Can you put a sample of a known size in the microscope an measure how many pixels that is?
     
  4. Dec 21, 2009 #3
    I see you did not understand my question .You see I know that my magnification on computer screen is 1000 times final .This I found out using Image J.What I am interested is do I have to include magnification of eyepiece which is 10x calculating total video magnification or I shouldnt do this and that makes 40objective x 25xadditional lense between beam splitter and video system.
    Somehow I believe that I shouldnt include eyepiece because light which comes from objectives is divided by prism into two separete beams one for eyepiece and one for video.And eyepiece magnification should not affect total video magnification.Am I right?Please confirm someone.
     
  5. Dec 21, 2009 #4

    mgb_phys

    User Avatar
    Science Advisor
    Homework Helper

    Is the camera attached to the eyepiece or is a builtin system?
    If it's built into the body of the microscope with a beamsplitter then the light never goes through the eyepiece, there will be a separate lens system to relay the image from the objective to the camera, this may or may not have any magnification.
    So the magnification at the sensor is objective mag * camera mag, but that is the size of the image on the chip - the size of the image on the screen depends on the screen and any digital zoom etc.

    It's really incorrect to talk about magnification for any system that forms an image
     
  6. Dec 21, 2009 #5
    The camera is built in the microscope not to an eyepiece. But video camera is not producing any magnification just transfering image to computer.That produces mahnification is objective and some aditional lense between prism(beam splitter) and video device.
    I was asking if eyepiece do some influence on total video magnification.I think no but I need someone to confirm me
     
  7. Dec 21, 2009 #6

    mgb_phys

    User Avatar
    Science Advisor
    Homework Helper

    No the eyepiece doesn't have any effect - but the relay lenses might have some magnification. Check the manual
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook