hello list,
I've try to look into that question but I probably looked in the wrong places.

It is widely said that in order to respect the famous Nyquist criteria, one should sample signals at 3 times the resolution of the acquisition system.
Hence if ia calcuate correctly, using a 0.80NA objective to image fluorescein at 520nm (which gives a 390nm resolution), one should set the zoom of a laser scanning system so that xy pixels have a size of 130nm.
BUT, what if the structures I am interested in are in the 1 to 5 µm range? In that case I do not really need the ful resolving power of my objective and using say 300nm pixel size should provide enough sampling to correctly image 1000nm objects, or? What do the expert say??
There are  practical aspects to this question.
- using a high zoom factor exposes living preps to large amount of potentially harmfull photons  
- when one scans a limited amount of pixels to increase frame frequency, zooming to nyqvist drastically reduces the field that is imaged
- I am working on pretty old data that I have no possibility whatsoever to re-acquire with a higher sampling rate ... ;^)
Thanks for your thougts
Eric
 
 
 
Eric Scarfone, PhD, CNRS, 
Center for Hearing and communication Research 
Department of Clinical Neuroscience 
Karolinska Institutet 

Postal Address: 
CFH, M1:02 
Karolinska Hospital, 
SE-171 76 Stockholm, Sweden 

Work: +46 (0)8-517 79343, 
Cell: +46 (0)70 888 2352 
Fax: +46 (0)8-301876 

email: [log in to unmask] 
http://www.ki.se/cfh/