In reply to Kees:

you wrote:
and the transmission is 100%, even when defining a rather broad passband
(try that with interference filters).

I think this is against all physics. As the Leica system uses beyond the
pinhole a prism  plus two lenses and several mirrors (I think at least
two mirrors for a two channel detection) there have to be losses. It
should be at least around 1% on each optical surface under optimal
conditions. This will sum up to around 8-10 % loss being now comparable
to very good bandpass filters. Confocal microscopes builders and users
still have to fight with the physical barriers.


In reply to Chip:

you wrote:
FYI- Zeiss does have a spectral option in the LSM series, but it is NOT
confocal (no pinhole). It is designed for use with the NLO
(multi-photon) systems where all fluorescence only comes from the plane
of focus.

The ZEISS spectrometer can be used as far as I know together with the
pinhole and and the advantage there is that you can get localized
complete spectra by using an ROI within a very short time (0.5 s). With
the LEICA system you have to record a series of images depending on the
needed resolution at different wavelength settings resulting quite often
in distorted spectra due to bleaching artefacts.

I aggree with Chip that in the end the best system will be a combination
of all features we are dreaming of.

Roland


___________________________

Nitschke, Roland Dr.

Institute of Physiology

Albert-Ludwigs-University Freiburg

Hermann-Herder-Str.7

D-79104 Freiburg

Germany
____________________________

E-Mail: [log in to unmask]
phone: 49-761-2035195
fax: 49-761-2035191