Re: simple test to compare confocals

Posted by Jeremy Adler-4 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Cosmic-ray-particles-centenary-The-Chase-2012-tp7578803p7578828.html

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Comparisons between instruments are difficult and tend of focus on  
resolution but one area that tends to be overlooked is noise.

A simple noise correction/measurement that we are pushing to  
accurately measure colocalization is to compare two images of the same  
specimen - the difference is the noise. This can be visualized either  
by subtraction or by plotting the intensities of pixels in the two  
images against each other - a standard scattergram. The scattergram  
makes the level of noise blindingly obvious and the method could  
easily be implemented during acquisition, when users have the chance  
to do something about it, but currently it is not available in any  
commercial software.

Noise clearly depends on acquisition time but ultimately is limited by  
photobleaching - a compeletly bleached image has had all the available  
information extracted. So a method of comparing microscopes is to  
measure the noise for a similar amount of photobleaching.








Quoting Arvydas Matiukas <[hidden email]>:

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>
> Dear List,
>
> I am looking for  simple and quick test (and sample) to compare
> acquisition across different confocals. Specifically, to our LSM510
> there was recently added Nikon C2 , and users want to know how
> they compare by few practical parameters, e.g. signal sensitivity,
> spectral bleedthrough, bleaching, and  maybe resolution  .
>
> I am aware of papers by Zucker, Pawley, Cole that describe detail
> evaluation of confocal performance, and even recently measured
> some PSFs. However, I am looking for just simple and quick
> test that would allow direct visual comparison of images (simple
> analysis like getting intensity histogram is fine) acquired on different
> confocals.
>
> Please share your thoughts and/or experience.
>
> Thank you in advance,
> Arvydas
> ***************************
>
>
> Arvydas Matiukas, Ph.D.
> Director of Confocal&Two-Photon Core
> Department of Pharmacology
> SUNY Upstate Medical University
> 766 Irving Ave., WH 3167
> Syracuse, NY 13210
> tel.: 315-464-7997
> fax: 315-464-8014
> email: [hidden email]
>



Jeremy Adler
IGP
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