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Nathalie Garin wrote:
> The Leica was great BUT to obtain an image equivalent on the Leica RS as
>on a spinning disk, we had to increase the average number, doing so
>reduces the speed of acquisition to the same speed as a standard confocal.
>In summary, we obtain the same image on the RS as on a standard confocal
>at the same speed. We bought the spinning disk.

With no disrespect intended, this is the result you'd expect.  The Leica
RS is no different optically to the slow scan model so you should get the
same image on both with the same accumulation time.  High speed spot
scan confocals (whether Leica RS or the now discontinued Bio-Rad/Nikon
RTS 2000) will give you true, fully confocal images at high speed and
if your signal is bright enough this can be really useful.

Sampling 1000 spots at the same time (Yokogawa-based system) will
give you much better s/n for a given time of aaccumulation - the price
is some sacrifice of confocality.

Sampling 1,000,000 points at the same time (ie CCD camera) will
give you even better s/n for a given time of accumulation at the price
of a total sacrifice of confocality!

There's really no way around this tradeoff, and in the end it's the
experiment that will drive the purchase decision.

The advantage of something like an RS is that you can use it at high
speed but at the same time you still have almost all of the features
of a high-performance slow-scan confocal - which you don't have with
a Yokogawa system.  So for mixed use and a limited budget it would
seem to have a useful place.

                                                 Guy Cox

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