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Hi Benedikt,

we acquired a Leica resonant scanner based confocal about 6 months ago. 
Before buying this system we tested different types of microscopes 
including three spinning disc based systems (Andor, PE and Visitec 
QLC100), two point-scan based systems (Leica and Visitec Eye) and the 
new Zeiss LSM5 Live system. We brought our own samples (transgenic plant 
material) and used these to test the different systems in terms of 
speed, photobleaching and overall image quality.

We found the spinning disc based systems to be slightly faster than the 
Leica system especially when acquiring square images (e.g. 512x512 
pixels). However the speed of the Leica system increases significantly 
when you reduce the number of lines in the Y direction. You should have 
no problem acquiring 10 fps with a resolution of 512x512 pixels 
resolution and about 15-20 fps with a resolution of 512x128 pixels.

In our experience the level of photobleaching is quite low when using 
the Leica system. I would say it is comparable to the spinning disc 
systems we tested and significantly lower than the Visitec Eye system 
that bleached my sample (transgenic GFP5-ER plants) within seconds (this 
system did however work nicely for calcium imaging in dendrites so the 
level of photobleaching depends on the properties of the fluorechrome).

In the end we chose the Leica system because it was sufficiently fast, 
had an adjustable and round pinhole making it fully confocal, had low 
levels of photobleaching, had a very flexible bandpass filter solution 
and could easily and relatively cheaply be upgraded to a tandem scanner 
system (both resonant and conventional scanner in the same system).


Best regards
Martin Seem
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Martin Seem
Graduate student
Group for Cell and Molecular Biology
Norwegian University of Science and Technology