how to convert pixel to micrometer ? - (Sep/25/2011 )
my friend wiredly and also stupidly collected the data of size of cells in pixel instead of micrometer what he could see under the microscope. but now all of these samples were discarded and no way we can do the experiment again.
so the problem of converting pixel to micrometer of cell size comes now.
if you know the solution, please share.
Millions thanks in advance.
If he knows the microscope settings he used for making those pictures, he could try taking a picture of an object with known dimensions and use that to calculate the scale.
K.B. on Sun Sep 25 19:02:11 2011 said:
If he knows the microscope settings he used for making those pictures, he could try taking a picture of an object with known dimensions and use that to calculate the scale.
Hi thanks for your input.
other than doing another experiment to calculate the result, can we just do some conversion calculation ? he used 40X magnfication - oild immersion.
40x magnification only means 40 units under the microscope equals to 1 unit in macro scale - it doesn't transform into pixel-micron relationship. (And by the way - to get real magnification you need to multiply by magnification of ocular lens and any other optical element between objective and camera that has magnification written on the body.)
You need to use a stage micrometer, which is a ruler measuring in micrometers on a slide (ask a teaching lab technician) and take a picture with it on the same microscope. You can't just convert magnification!
You can then use the scale bar tool in ImageJ to convert pixels to micrometers.
Little late here. Depending on the microscope the images were taken on this information may actually be in the image files (e.g. .lsm) themselves. Have you tried opening up ImageJ the 'scale' will be shown above the top of the image, or go to Analyze > Set Scale... and see what it says there.