Mathematically
Th number of pixels the image of a cell takes on the CCD camera depends on:
1. the magnification used, and on
2. the physical size of the pixels on the CCD camera (in our case, it is 6.45um)
In order to relate the size of a cell in pixels to its size in um, use the following formula:
Cell size (per pixel) = Physical length of a pixel on the CCD / total magnification
The physical length of a pixel on our CCD is 6.45um. So for the following magnification, this formula gives us:
l 100x : 0.0645 um/pixel or 15.50 pixels/um
l 90x : 0.0717 um/pixel or 13.95 pixels/um
l 60x : 0.1075 um/pixel or 9.30 pixels/um
l 40x : 0.1613 um/pixel or 6.21 pixels/um
l 20x : 0.3225 um/pixel or 3.10 pixels/um
l 10x : 0.645 um/pixel or 1.55 pixel/um
Important notes:
l We assumed here that the magnifier is at position 1x (not 1.5x). If it is at 1.5x, total magnification must be multiplied by 1.5.
l We assumed here that the bin size is 1x1. If it is, say, 2x2, the size of a pixel will be double.
l 90x corresponds to 60x objective with 1.5x intermediate magnification