While carrying measurements of certain diptera flies I used the compound microscope but I am getting wrong answers from it. Kindly suggest a method of taking measurements of certain insects under compound microscope [having 10X eyepiece with ocular micrometer(0.01mm)]
Kindly also suggest me any formula to calculate insect with different objective lens.
Thank u GD
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Nilotpol
Hope this will be helpful
https://www.youtube.com/watch?v=bojLX5_U8hg
You need an objective micrometer, i.e. a microscope slide that has engraved a scale in real size, usually 1 mm divided in 100. With every ocular (eyepiece) you measure the true size of each division in the ocular micrometer. In my microscope, every division of the ocular micrometer for 10X is 1 um, for 40X is 2.5 um, and so on.
Abhijit, as Sven has put it, you must use a calibration scale. This will be in the form of a microscope slide with a minute scale, consisting of multiple subdivisions, each often subdivided again. The length of the scale and number and length of the subdivisions should be given on the slide itself or in the storage box.
You then place the calibration slide on the microscope stage and observe it at the desired magnification using your ocular micrometer. You must measure the number of micrometers on the calibration slide that correspond to a convenient interval (10 µm=0.01 mm) on your ocular micrometer. This must be done for each objective. The ocular micrometer units are not important, they serve as a reference scale only.
Knowing this relationship, you can then measure your insect parts using the ocular micrometer units alone and convert to the calibrated real dimension by multiplying by the corresponding number of micrometers.
You need a calibrated slide with markings down to one micron if possible and then match up the markings on your ocular micrometer with the slide measurements. Be sure the slide is certified for accuracy.
Hello Abhijit. You will need a stage micrometer (predetermined and calculated scale on a slide) and measure the ocular micrometer with it to calibrate the ocular micrometer ( or graticule). Here are the instructions: https://www.youtube.com/watch?v=8TIyj8OrtWA
The best way is to locate the measuring ocular lens in its place and put the part you need to measured under the compound microscope and adjust the lenses to get the most clear vision, so after that you replace the part with the stage ruler, and standardize the true length of each single line of the ocular lens measurements, then remove the stage ruler and start measuring the parts with the ocular ruler and after you finished multiply the number of lines with the value you got from the standardization formula so you will get the true length of the parts.
If you need more clarification or any help please do not hesitate to contact me.
The answer by Ahmed should help you and Note, the size you get is magnified x10 by the eyepiece lenses which has also magnified the graduations of the ocular micrometer.
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