Hello!

Is anyone aware of a similar procedure for the
Zeiss LSM410. We were wondering for some time
whether the PTMs are linear and how to compare
quantitatively data that was acquired with all
settings constant, but different contrast
settings (300 vs 270)

Heiko Possel


> > We have a Leica confocal microscope. Is the PMT linear over the whole
> > range or should it be used at lower values. How does one deterime the
> > noise of a PMT?
> > Robert Zucker
> >
>
>  All of the PMT's are actually fully configurable regarding their
> video-adc characteristics.
>  The default does use a linear scale, but the software comes with a
> function to change this to an exponential or logarithmic one.  You
> can also input your own values.
>  I am assuming you are using ScanWare;
> Go into the scan window, hit the 'special' button below the channel
> selection area, then hit the 'transm. gamma' button,  this reveals
> a window with the characteristics graph.  If I remember correctly the
> x-axis is the plot of the intensity hitting the pmt, while the y-axis
> is the intensity displayed on the monitors.
>  Selecting the logarithmic application parameter set (should already
> be defined) changes the characteristics of that particular pmt so
> that it is mainly the high signal that is displayed .. ie. 'background'
> is reduced.  On the other hand the exponential set will bring up the
> 'background' while showing the higher signal diminished in intensity.
> Assuming I have the axis the right way round !!  Must admit, I suck
> this one and see!
>
> Hope this helps,
>
> Andy
>
>
> Andy Hubbard, Confocal Microscopy Technician,
> CMHT., Leicester University, P.O. Box 138.
> Tel. - (0116) 2525625;  Fax. - (0116) 2525616
> e-mail - [log in to unmask]
>
>
Heiko Possel
Institut fuer Medizinische Neurobiologie

Leipziger Strasse 44

39120 Magdeburg

Telefon 0391-67-14362
Fax     0391-67-14365