> testing of several systems, especially the Leica and Zeiss, since
> they seemed to be the ones most recommended by others.  The Leica has
> the clear advantage of wavelength flexibility due to its
> spectrophotometer based system and the ability to detect at any
> wavelength. The Zeiss is like other systems in being filter based and
> so you are at the mercy of the filters you buy, which is no problem
> for most of the things most people will do.  Zeiss has an edge in
>

David,
I don't think this is correct any longer. At the FOM2001 it was announced by
Zeiss officials that there is a new spectrometer addition available to the
LSM510. This one takes a novel approach using a PMT array with a diffaction
grating. The wavelength range is selected by the corresponding PMT elements.
Alternatively all elements or any selection can be chosen to produce
multi-wavelength images. In my opinion a diffraction grating offers better
optical properties. Besides the linear spectrum, it has only one surface
that can attenuate fluorescent emissions, whereas glass prism's have at
least two. Additionally, the wavelength scale is not linear on prism's.


Cheers
Lutz

______________________________________
Lutz Schaefer
Advanced Imaging Methodology Consultation
16-715 Doon Village Rd.
Kitchener, Ontario
N2P 2A2, Canada
Email: [log in to unmask]
Phone, FAX: (519)-894-8870
______________________________________