I need to measure cells and tissues. For this purpose i have to use scales in different magnittudes (10x, 20x, 40x,60x and 100x) . The problem is that I don´t have the images of the scales to use for this measures. Can anyone help me and send the pictures??
Unless somebody has exactly the same microscope, objectives (extension tube magnifier, if any) and camera you cannot assume that you have the same scales just because you are both using a x10 lens.
Best thing is to borrow a stage micrometer from somebody and photograph it with all your lenses. Then calculate the pixel size for each objective. You only need to do that once, unless you have a microscope with a zoom (in which case you will have to do it for each shot).
Even using “internal” references (like an erythrocyte or a lymphocyte) is not reliable as there is an unknown percentage of shrinkage due to the fixation process.
Does the image have any metadata which may have this information?