(NOTE) The **Pixel Size** is a “what is the physical size of each pixel of the image?”
On a system with a camera the pixel size is function of the :
- Camera (what is the size of a pixel on the camera)
- Objective magnification
- Binning (to you put adjacent pixels together , that makes pixel bigger, image has less pixels, higher sensitivity)
- [presence of an additional lens in the light path (to make it simple : C-mount if it’s hold the camera , Optovar on other systems)]
On a Point Scanning Confocal equipped with PMT (or fancier device) you scan one pixel at a time, one after another. The pixel size is function of the :
- Microscope
- Objective magnification
- Zoom
- Number of pixels of your image
So on a defined microscope, for a defined Objective magnification and Zoom if you make an image with 256, 512 or 1024 pixels your Pixel Size will get smaller and smaller (0.2 um, 0.1 um, 0.05um per pixel).
(NOTE) The **Resolution **( or Resolution Power) would be “What is the closest distance between 2 points so you can discriminate them in your image?”.
The N.A. of the objective will affect your resolution power, so does the wavelength you use (see Abbe diffraction limit )
(IMPORTANT) We recommend to save images using the company format (that bio-formats can read ) while TIF exported by company softwares usually export wrong values or with wrong keys , so Bio-formats can’t read metadata correctly and you end up with cm or inches !