Original source: http://www.microscopiaoberta.com/?p=184&lang=ca

The separating power (A.K.A. resolution) of a microscope is not given by the camera but by the objective of the microscope.

It is a classic that our customers ask us for digital cameras of “when more megapixels better” but the reality is that the separating power (A.K.A. resolution) of a microscope is NOT given by the camera but the objective of the microscope

In the market there are microscope cameras from 1 to 32 Megapixels, 5 and 10 Megapixels being usual, but if the separating power / resolution is not given by the camera then how many pixels are necessary to work in microscopy?

First point – The Separating power (A.K.A. Resolution) of a microscope

To determine pixels we need before we must know the separating power of our microscopes.

This parameter is mainly determined by the Numerical Opening of our objectives and is defined by the following simplified formula:

Second point – Nyquist theorem

We already have the resolution of our objectives, but how does it translate into pixels?

To do this, we use the Nyquist Theorem that will determine the ideal pixel size for each of our objectives. A formula for calculating the IDEAL pixel size in microscopy is:


Third point – Camera Sensor Size

Now we know what dimensions it is necessary for our pixels to solve, in maximum detail, the images of our microscopes but we need to translate the size of 1 pixel to the resolutions we use with our cameras.

The simplest formula is:

The simplest way is:

IMPORTANT! Above the obtained megapixel value we will be over sampling the image and we will not get more information. Below the value we lose information and it is not recommended at all.